USACE / NAVFAC / AFCESA / NASA UFGS-04 20 00 (February 2009)
-----------------------------
Preparing Activity: USACE Superseding
UFGS-04 20 00 (October 2007)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 04 20 00
MASONRY
02/09
NOTE: This guide specification covers the requirements for reinforced and nonreinforced
masonry.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
This guide specification includes tailoring options for Navy, CMU, brick, PC
items, stone, prefaced CMU and insulation. Selection or deselection of a tailoring
option will include or exclude that option in the section, but editing the resulting
section to fit the project is still required.
PART 1 GENERAL
NOTE: This guide specification covers reinforced and nonreinforced masonry
and must be tailored to reflect the type of construction used in the design.
In general, reinforced masonry is defined as masonry construction which contains
vertical bar reinforcement, horizontal bar or joint reinforcement, mortar, and
grout combined in a manner that the component materials will act together to
resist the design loading conditions. Design will conform to ACI 530/530.1/ASCE
5 BUILDING CODE REQUIREMENTS FOR MASONRY STRUCTURES.
Masonry not meeting the above definition but bonded together with mortar and
containing, if necessary, the minimum amount of reinforcement for crack control
and vertical stiffeners, is classified as nonreinforced masonry.
The following information will be shown on the project drawings:
1. Locations and dimensions of each type of masonry work; wall sections and
anchor details.
2. Color, texture, and size of brick and color of mortar if other than natural
gray.
3. Bond pattern if other than running bond.
4. All flashing locations and details.
5. Control joint and expansion joint locations and details.
6. Special brick shapes if required.
7. Compressive strength (f'm) of units, mortar, grout, or entire assembly and
fy of reinforcing.
8. Reinforcing tie, splice, and bond beam details.
9. Size and location of any pipes, ducts, door and window framing, or other
embedded items.
10. Equivalent thickness or UL assembly for fire rated walls.
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[ACI INTERNATIONAL (ACI)ACI 318(2008; Errata 2008) Building Code Requirements for Structural Concrete and CommentaryACI 318M(2008) Metric Building Code Requirements for Structural Concrete and CommentaryACI 530/530.1(2008) Building Code Requirements and Specification for Masonry Structures; Containing Building Code Requirements for Masonry Structures, Specification for Masonry Structures and Companion CommentariesACI SP-66(2004) ACI Detailing Manual][ASTM INTERNATIONAL (ASTM)ASTM A 153/A 153M(2005) Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel HardwareASTM A 167(1999; R 2004) Standard Specification for Stainless and Heat-Resisting Chromium-Nickel Steel Plate, Sheet, and StripASTM A 615/A 615M(2008b) Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete ReinforcementASTM A 641/A 641M(2003) Standard Specification for Zinc-Coated (Galvanized) Carbon Steel WireASTM A 82/A 82M(2007) Standard Specification for Steel Wire, Plain, for Concrete ReinforcementASTM B 370(2003) Standard Specification for Copper Sheet and Strip for Building ConstructionASTM C 1019(2008a) Standard Test Method for Sampling and Testing GroutASTM C 1072(2006) Standard Test Method for Measurement of Masonry Flexural Bond StrengthASTM C 1142(1995; R 2007) Standard Specification for Extended Life Mortar for Unit MasonryASTM C 129(2006) Standard Specification for Nonloadbearing Concrete Masonry UnitsASTM C 140(2008a) Standard Test Methods for Sampling and Testing Concrete Masonry Units and Related UnitsASTM C 144(2004) Standard Specification for Aggregate for Masonry MortarASTM C 150(2007) Standard Specification for Portland CementASTM C 207(2006) Standard Specification for Hydrated Lime for Masonry PurposesASTM C 216(2007a) Facing Brick (Solid Masonry Units Made from Clay or Shale)ASTM C 27(1998; R 2008) Fireclay and High-Alumina Refractory BrickASTM C 270(2008a) Standard Specification for Mortar for Unit MasonryASTM C 315(2007) Clay Flue LiningsASTM C 476(2008) Standard Specification for Grout for MasonryASTM C 494/C 494M(2008a) Standard Specification for Chemical Admixtures for ConcreteASTM C 55(2006e1) Concrete BrickASTM C 593(2006) Fly Ash and Other Pozzolans for Use with LimeASTM C 62(2008) Building Brick (Solid Masonry Units Made from Clay or Shale)ASTM C 641(2007) Staining Materials in Lightweight Concrete AggregatesASTM C 652(2007) Hollow Brick (Hollow Masonry Units Made from Clay or Shale)ASTM C 67(2008) Standard Test Methods for Sampling and Testing Brick and Structural Clay TileASTM C 73(2005) Calcium Silicate Brick (Sand-Lime Brick)ASTM C 744(2008) Prefaced Concrete and Calcium Silicate Masonry UnitsASTM C 780(2008) Preconstruction and Construction Evaluation of Mortars for Plain and Reinforced Unit MasonryASTM C 90(2008) Loadbearing Concrete Masonry UnitsASTM C 91(2005) Masonry CementASTM C 94/C 94M(2007) Standard Specification for Ready-Mixed ConcreteASTM C 989(2006) Standard Specification for Ground Granulated Blast-Furnace Slag for Use in Concrete and MortarsASTM D 1972(1997; R 2005) Standard Practice for Generic Marking of Plastic ProductsASTM D 2000(2008) Standard Classification System for Rubber Products in Automotive ApplicationsASTM D 2240(2005) Standard Test Method for Rubber Property - Durometer HardnessASTM D 2287(1996; R 2001) Nonrigid Vinyl Chloride Polymer and Copolymer Molding and Extrusion CompoundsASTM E 119(2008a) Standard Test Methods for Fire Tests of Building Construction and MaterialsASTM E 2129(2005) Standard Practice for Data Collection for Sustainability Assessment of Building ProductsASTM E 514(2008) Water Penetration and Leakage Through Masonry][INTERNATIONAL CODE COUNCIL (ICC)ICC IBC(2006; Errata 2006; Errata 2007; Supplement 2007; Errata 2007) International Building Code][U.S. DEPARTMENT OF DEFENSE (DOD)UFC 3-310-04(2007) Seismic Design for Buildings][U.S. GREEN BUILDING COUNCIL (USGBC)LEED(2002; R 2005) Leadership in Energy and Environmental Design(tm) Green Building Rating System for New Construction (LEED-NC)]
1.2 SYSTEM DESCIPTION
1.2.1 Local/Regional Materials
NOTE: Using local materials can help minimize transportation impacts, including
fossil fuel consumption, air pollution, and labor. Using materials harvested
and manufactured within a 500 mile radius from the project site contributes
to the following LEED credit: MR5. Coordinate with Section 01 33 29 LEED(tm)
DOCUMENTATION. Use second option if Contractor is choosing local materials
in accordance with Section 01 33 29 LEED(tm) DOCUMENTATION. Use second option
for USACE projects. Army projects shall include option only if pursuing this
LEED credit.
[Use materials or products extracted, harvested, or recovered, as well as manufactured, within a [800][_____]
km [500][_____] mile radius from the project site, if available from a minimum of three sources.][See Section
01 33 29 LEED(tm) DOCUMENTATION for cumulative total local material requirements. Masonry materials may be locally
available.]
1.2.2 Environmental Data
NOTE: ASTM E 2129 provides for detailed documentation of the sustainability
aspects of products used in the project. This level of detail may be useful
to the Contractor, Government, building occupants, or the public in assessing
the sustainability of these products.
[Submit Table 1 of ASTM E 2129 for the following products: [_____].]
1.2.3 Plastic Identification
NOTE: The marking system indicated below is intended to provide assistance
in identification of products for making subsequent decisions as to handling,
recycling, or disposal.
Verify that plastic products to be incorporated into the project are labeled in accordance with ASTM D 1972.
Where products are not labeled, provide product data indicating polymeric information in the Operation and Maintenance
Manual.
a. Type 1: Polyethylene Terephthalate (PET, PETE).
b. Type 2: High Density Polyethylene (HDPE).
c. Type 3: Vinyl (Polyvinyl Chloride or PVC).
d. Type 4: Low Density Polyethylene (LDPE).
e. Type 5: Polypropylene (PP).
f. Type 6: Polystyrene (PS).
g. Type 7: Other. Use of this code indicates that the package in question is made with a resin other
than the six listed above, or is made of more than one resin listed above, and used in a multi-layer
combination.
1.2.4 Design Requirements
1.2.4.1 Unit Strength Method
NOTE: Use this method for clay masonry conforming to ASTM C 216, ASTM C 62,
or ASTM C 652, and tested by ASTM C 67, with bed joints not exceeding 16 mm
(5/8 inch) and grouted, ASTM C 476, with strength at least equal to f'm, and
also for concrete masonry units conforming to ASTM C 90 or ASTM C 55, with bed
joints and grout same as clay masonry. If masonry does not meet these requirements,
use Prism Test Method.
Compute compressive strength of masonry system "Unit Strength Method," ACI 530/530.1. Submit calculations and
certifications of unit and mortar strength.
1.2.4.2 Seismic Requirement
NOTE: For Army projects refer to UFC 3-310-04; for Navy projects refer to minimum
seismic reinforcing required in NAVFAC P-355, Chapter 13.
In addition to design requirements of ICC IBC, provide additional seismic reinforcement [in accordance with UFC 3-310-04
] [as detailed on [the drawings] [sketches [_____] which are attached at the rear of this section]]. The total
minimum reinforcing percentage for structural walls shall be 0.20 percent and non-structural walls shall be 0.15
percent. The maximum spacing of reinforcing bars shall be as follows:
Wall Type Vertical Horizontal
Structural 0.609 m 1.219 m
Non-structural 1.219 m 2.032 m
Wall Type Vertical Horizontal
Structural 24 inches 48 inches
Non-structural 48 inches 80 inches
Bond beams are required at the top of footings, at the bottom and top of openings at roof and floor levels, and
at the top of parapet walls.
1.2.4.3 Special Inspection
NOTE: Include this paragraph only when special inspection and testing for seismic-resisting
systems is required by Chapter 2 of FEMA 450, NEHRP RECOMMENDED PROVISIONS FOR
SEISMIC REGULATIONS FOR NEW BUILDINGS AND OTHER STRUCTURES.
This paragraph will be applicable to both new buildings designed according UFC
3-310-04 SEISMIC DESIGN FOR BUILDINGS, and to existing building seismic rehabilitation
designs.
The designer must indicate on the drawings all locations and all features for
which special inspection and testing is required in accordance with UFC 3-310-04
and Chapter 2 of FEMA 450. This includes indicating the locations of all structural
components and connections requiring inspection.
Add any additional requirements as necessary.
Perform special inspections and testing for seismic-resisting systems and components in accordance with UFC 3-310-04
SEISMIC DESIGN FOR BUILDINGS and Section 01 45 35 SPECIAL INSPECTION FOR SEISMIC-RESISTING SYSTEMS.
1.2.4.4 Masonry Strength
Determine masonry strength in accordance with ACI 530/530.1; submit test reports on three prisms as specified
in ACI 530/530.1. The cost of testing shall be paid by the Contractor.
1.2.5 Additional Requirements
NOTE: On small projects, requirement for spare vibrator may be deleted.
a. Maintain at least one spare vibrator on site at all times.
b. Provide bracing and scaffolding necessary for masonry work. Design bracing to resist wind pressure
as required by local code.
1.2.6 Metrication
The Contractor has the option to use either hard metric or substitute inch-pound (soft-metric) CMU products.
If the Contractor decides to substitute inch-pound CMU products, the following additional requirements shall
be met:
a. The metric dimensions indicated on the drawings shall not be altered to accommodate inch-pound CMU
products either horizontally or vertically. The 100 mm building module shall be maintained, except for
the CMU products themselves.
b. Mortar joint widths shall be maintained as specified.
c. Rebars shall not be cut, bent or eliminated to fit into the inch-pound CMU products module.
d. Brick and inch-pound CMU products shall not be reduced in size by more than one-third (1/3) in height
and one-half (1/2) in length. Cut CMU products shall not be located at ends of walls, corners, and other
openings.
e. Cut, exposed brick and CMU products shall be held to a minimum and located where they would have
the least impact on the architectural aesthetic goals of the facility.
f. Other building components, built into the CMU products, such as window frames, door frames, louvers,
grilles, fire dampers, etc., that are required to be metric, shall remain metric.
g. Additional metric guidance shall conform to Section 00 31 10 METRIC MEASUREMENTS.
1.3 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are for [Contractor Quality Control approval.] [information only. When used, a designation following the "G"
designation identifies the office that will review the submittal for the Government.] Submit the following in
accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Detail Drawings[; G][; G, [_____]]
Drawings including plans, elevations, and details of wall reinforcement; details of reinforcing
bars at corners and wall intersections; offsets; tops, bottoms, and ends of walls; control and
expansion joints; lintels; and wall openings.
SD-03 Product Data
[Local/Regional Materials; (LEED)
Documentation indicating distance between manufacturing facility and the project site, and
distance of raw material origin from the project site. Indicate relative dollar value of local/regional
materials to total dollar value of products included in the project.]
[Environmental Data]
Clay or Shale Brick[; G][; G, [_____]]; (LEED)
Concrete Brick[; G][; G, [_____]]
Concrete Masonry Units (CMU)[; G][; G, [_____]]; (LEED)
Cement[; G][; G, [_____]]; (LEED)
Insulation[; G][; G, [_____]]
Flashing[; G][; G, [_____]]
Water-Repellant Admixture[; G][; G, [_____]]
Manufacturer's descriptive data. Documentation indicating percentage of post-industrial and
post-consumer recycled content per unit of product. Indicate relative dollar value of recycled
content products to total dollar value of products included in project.
Cold Weather Installation[; G][; G, [_____]]
Cold weather construction procedures.
Salvaged Brick[; G][; G, [_____]]; (LEED)
Documentation certifying products are from salvaged/recovered sources. Indicate relative
dollar value of salvaged content products to total dollar value of products included in project.
SD-04 Samples
Concrete Masonry Units (CMU)[; G][; G, [_____]]
Concrete Brick[; G][; G, [_____]]
Stone Items[; G][; G, [_____]]
Clay or Shale Brick[; G][; G, [_____]]
Color samples of three stretcher units and one unit for each type of special shape. Units
shall show the full range of color and texture. Submit sample of colored mortar with applicable
masonry unit.
Anchors, Ties, and Bar Positioners[; G][; G, [_____]]
Two of each type used.
Expansion-Joint Materials[; G][; G, [_____]]
One piece of each type used.
Joint Reinforcement[; G][; G, [_____]]
One piece of each type used, including corner and wall intersection pieces, showing at least
two cross wires.
Insulation[; G][; G, [_____]]
One piece of board type insulation, not less than 400 by 600 mm 16 by 24 inches in size, containing
the label indicating the rated permeance and R-values.
Portable Panel[; G][; G, [_____]]
One panel of clay or shale brick, 600 by 600 mm 2 by 2 feet, containing approximately 24 brick
facings to establish range of color and texture.
SD-05 Design Data
Pre-mixed Mortar[; G][; G, [_____]]
Unit Strength Method[; G][; G, [_____]]
Pre-mixed mortar composition. Calculations and certifications of masonry unit and mortar
strength.
SD-06 Test Reports
Efflorescence Test[; G][; G, [_____]]
Field Testing of Mortar[; G][; G, [_____]]
Field Testing of Grout[; G][; G, [_____]]
Prism tests[; G][; G, [_____]]
Masonry Cement[; G][; G, [_____]]
Fire-rated CMU[; G][; G, [_____]]
Test reports from an approved independent laboratory. Test reports on a previously tested
material shall be certified as the same as that proposed for use in this project.
Masonry Inspector Qualifications[; G][; G, [_____]]
Copies of masonry inspector reports.
SD-07 Certificates
Clay or Shale Brick
Concrete Brick
Concrete Masonry Units (CMU)
Control Joint Keys
Anchors, Ties, and Bar Positioners
Expansion-Joint Materials
Joint Reinforcement
Reinforcing Steel Bars and Rods
Masonry Cement
Mortar Coloring
Insulation
Precast Concrete Items
Admixtures for Masonry Mortar
Admixtures for Grout
Certificates of compliance stating that the materials meet the specified requirements.
Insulation
Certificate attesting that the polyurethane or polyisocyanurate insulation furnished for the
project contains recovered material, and showing an estimated percent of such recovered material.
Contamination
SD-08 Manufacturer's Instructions
Masonry Cement
When masonry cement is used, submit the manufacturer's printed instructions on proportions
of water and aggregates and on mixing to obtain the type of mortar required.
SD-10 Operation and Maintenance Data
Plastic Identification
When not labeled, identify types in Operation and Maintenance Manual.
Take-Back Program
Documentation that includes contact information, summary of procedures, and the limitations
and conditions applicable to the project. Indicate manufacturer's commitment to reclaim materials
for recycling and/or reuse.
1.4 QUALITY ASSURANCE
1.4.1 Appearance
NOTE: A typical manufacturing batch of brick produces about 150,000 brick.
Confirm with manufacturer if the job can be run in one batch to utilize the
desirable bracketed option in the following paragraph.
[Manufacture bricks at one time and from the same batch.] Blend all brick to produce a uniform appearance when
installed. An observable "banding" or "layering" of colors or textures caused by improperly mixed brick is unacceptable.
1.4.2 Contamination
When using bricks containing contaminated soil, supplier shall certify that the hazardous waste is neutralized
by the manufacturing process and that no additional pollutants will be released, or that the product is free
from hazardous contaminants.
1.4.3 Sample Masonry Panels
NOTE: Sample panels will be required for structures having over 185 square
meters (2,000 square feet) of exterior wall area, including openings, and for
smaller structures where appearance is important. The list of items to be shown
by the sample panel will be edited to provide only the representative items.
Typical installation of electrical conduit and boxes may be illustrated by the
sample panel when deemed appropriate.
After material samples are approved and prior to starting masonry work, construct a portable panel of clay or
shale brick and sample masonry panels for each type and color of masonry required. At least 48 hours prior to
constructing the sample panel or panels, submit written notification to the Contracting Officer. Sample panels
shall not be built in, or as part of the structure, but shall be located where directed.
1.4.3.1 Configuration
Panels shall be L-shaped or otherwise configured to represent all of the wall elements. Panels shall be of the
size necessary to demonstrate the acceptable level of workmanship for each type of masonry represented on the
project. The minimum size of a straight panel or a leg of an L-shaped panel shall be 2.5 m 8 feet long by [1.2]
[1.8] m [4] [6] feet high.
1.4.3.2 Composition
Panels shall show full color range, texture, and bond pattern of the masonry work. The Contractor's method for
mortar joint tooling; grouting of reinforced vertical cores, collar joints, bond beams, and lintels; positioning,
securing, and lapping of reinforcing steel; positioning and lapping of joint reinforcement (including prefabricated
corners); and cleaning of masonry work shall be demonstrated during the construction of the panels. Installation
or application procedures for anchors, wall ties, CMU control joints, brick expansion joints, insulation, flashing,
brick soldier, row lock courses and weep holes shall be shown in the sample panels. The panels shall contain
[a masonry bonded corner] [a stacked bond corner] that includes a bond beam corner. Panels shall show [parging]
[and] [installation of electrical boxes and conduit]. Panels that represent reinforced masonry shall contain
a 600 by 600 mm 2 by 2 foot opening placed at least 600 mm 2 feet above the panel base and 600 mm 2 feet away
from all free edges, corners, and control joints. Required reinforcing shall be provided around this opening
as well as at wall corners and control joints.
1.4.3.3 Construction Method
Where anchored veneer walls are required, demonstrate and receive approval for the method of construction; i.e.,
either bring up the two wythes together or separately, with the insulation and appropriate ties placed within
the specified tolerances across the cavity. Temporary provisions shall be demonstrated to preclude mortar or
grout droppings in the cavity and to provide a clear open air space of the dimensions shown on the drawings.
Where masonry is to be grouted, demonstrate and receive approval on the method that will be used to bring up
the masonry wythes; support the reinforcing bars; and grout cells, bond beams, lintels, and collar joints using
the requirements specified herein. If sealer is specified to be applied to the masonry units, sealer shall be
applied to the sample panels. Panels shall be built on a properly designed concrete foundation.
1.4.3.4 Usage
The completed panels shall be used as the standard of workmanship for the type of masonry represented. Masonry
work shall not commence until the sample panel for that type of masonry construction has been completed and approved.
Panels shall be protected from the weather and construction operations until the masonry work has been completed
and approved. After completion of the work, the sample panels, including all foundation concrete, shall become
the property of the Contractor and shall be removed from the construction site.
1.4.4 Masonry Inspector Qualifications
NOTE: This paragraph will be used for masonry construction only when f'm used
in design is more than 10 MPa (1500 psi).
A qualified masonry inspector approved by the Contracting Officer shall perform inspection of the masonry work.
Minimum qualifications for the masonry inspector shall be 5 years of reinforced masonry inspection experience
or acceptance by a State, municipality, or other governmental body having a program of examining and certifying
inspectors for reinforced masonry construction. The masonry inspector shall be present during preparation of
masonry prisms, sampling and placing of masonry units, placement of reinforcement (including placement of dowels
in footings and foundation walls), inspection of grout space, immediately prior to closing of cleanouts, and
during grouting operations. The masonry inspector shall assure compliance with the drawings and specifications.
The masonry inspector shall keep a complete record of all inspections and shall submit daily written reports
to the Quality Control Supervisory Representative reporting the quality of masonry construction.
1.4.5 Detail Drawings
Submit detail drawings showing bar splice locations. If the Contractor opts to furnish inch-pound CMU products,
drawings showing elevation of walls exposed to view and indicating the location of all cut CMU products shall
be submitted for approval.. Bent bars shall be identified on a bending diagram and shall be referenced and located
on the drawings. Wall dimensions, bar clearances, and wall openings greater than one masonry unit in area shall
be shown. No approval will be given to the shop drawings until the Contractor certifies that all openings, including
those for mechanical and electrical service, are shown. If, during construction, additional masonry openings
are required, the approved shop drawings shall be resubmitted with the additional openings shown along with the
proposed changes. Location of these additional openings shall be clearly highlighted. The minimum scale for
wall elevations shall be 1 to 50 1/4 inch per foot. Reinforcement bending details shall conform to the requirements
of ACI SP-66.
1.5 DELIVERY, HANDLING, AND STORAGE
Materials shall be delivered, handled, stored, and protected to avoid chipping, breakage, and contact with soil
or contaminating material. Store and prepare materials in already disturbed areas to minimize project site disturbance
and size of project site.
1.5.1 Masonry Units
Cover and protect moisture-controlled concrete masonry units and cementitious materials from precipitation.
Conform to all handling and storage requirements of ASTM C 90. Prefabricated lintels shall be marked on top
sides to show either the lintel schedule number or the number and size of top and bottom bars.
1.5.2 Reinforcement, Anchors, and Ties
Steel reinforcing bars, coated anchors, ties, and joint reinforcement shall be stored above the ground. Steel
reinforcing bars and uncoated ties shall be free of loose mill scale and rust.
1.5.3 Cementitious Materials, Sand and Aggregates
Cementitious and other packaged materials shall be delivered in unopened containers, plainly marked and labeled
with manufacturers' names and brands. Cementitious material shall be stored in dry, weathertight enclosures
or be completely covered. Cement shall be handled in a manner that will prevent the inclusion of foreign materials
and damage by water or dampness. Sand and aggregates shall be stored in a manner to prevent contamination or
segregation.
1.6 PROJECT/SITE CONDITIONS
Conform to ACI 530/530.1 for hot and cold weather masonry erection.
1.6.1 Hot Weather Installtion
Take the following precautions if masonry is erected when the ambient air temperature is more than 37 degrees
C 99 degrees F in the shade and the relative humidity is less than 50 percent or the ambient air temperature
exceeds 32 degrees C 90 degrees F and the wind velocity is more than 13 km/h 8 mph. All masonry materials shall
be shaded from direct sunlight; mortar beds shall be spread no more than 1.2 m 4 feet ahead of masonry; masonry
units shall be set within one minute of spreading mortar; and after erection, masonry shall be protected from
direct exposure to wind and sun for 48 hours.
1.6.2 Cold Weather Installation
Before erecting masonry when ambient temperature or mean daily air temperature falls below 4 degrees C 40 degrees
F or temperature of masonry units is below 4 degrees C 40 degrees F, submit a written statement of proposed cold
weather construction procedures for approval. Take the additional following precautions if masonry is erected
in cold weather: [_____]
PART 2 PRODUCTS
2.1 GENERAL REQUIREMENTS
The source of materials which will affect the appearance of the finished work shall not be changed after the
work has started except with Contracting Officer's approval.
2.2 CLAY OR SHALE BRICK
NOTE: The manufacturer's name and color number or color range will be indicated
on the drawings along with the following note: "Colors or color ranges indicated
are for identification purposes only and are not intended to limit selection
of similar color or color range from other manufacturers."
Grade SW brick provides a high degree of resistance to frost action and deterioration
by weathering. Grade MW brick provides a moderate degree of resistance. Brick
facings may be limited to Grade SW units where previous experience indicates
that surfaces of Grade MW facings, 10 years of age in the project area, have
deteriorated due to weathering.
Types FBS and HBS brick are for general use where normal size variation and
color range is acceptable. Types FBX and HBX permit less variation. Types
FBA and HBA permit large variations for special architectural effect.
Bricks of various modular sizes are available and, if for architectural reasons,
other size bricks are included in the design, the nominal size selected shall
be specified as necessary. If larger units, such as utility brick are required,
change the specified dimensions. If nominal dimensions are used, they should
be so noted.
Use of materials with recycled content, calculated on the basis of post-industrial
and post-consumer percentage content, contributes to the following LEED credit:
MR4. Coordinate with Section 01 33 29 LEED(tm) DOCUMENTATION. Designer must
verify that products meeting the indicated minimum recycled content are available,
preferably from at least three sources, to ensure adequate competition. If
not, write in suitable recycled content values that reflect availability and
competition. Use second option if Contractor is choosing recycled content products
in accordance with Section 01 33 29 LEED(tm) DOCUMENTATION.
Color range and texture of clay or shale brick shall be as indicated and shall conform to the approved sample.
Brick shall conform to ASTM C 62; Grade SW shall be used for brick in contact with earth or grade and for [the
first six exterior courses above grade] [all exterior work] and for all nonvertical surfaces. Grade SW or MW
shall be used in other brickwork. Average dimensions of brick shall be 90 mm thick, 57 mm high, and 190 mm long
(standard) 3-5/8 inches thick, 2-1/4 inches high, and 8 inches long (standard) or 4 inches thick, 2-2/3 inches
high, and 8 inches long (nominal), subject to the tolerances specified in ASTM C 62. Brick shall be tested for
efflorescence. Clay or shale brick units shall be delivered factory-blended to provide a uniform appearance
and color range in the completed wall. [Clay units shall contain a minimum of [5][10][_____] percent post-consumer
recycled content, or a minimum of [20][40][_____] percent post-industrial recycled content.][See Section
01 33 29 LEED(tm) DOCUMENTATION for cumulative total recycled content requirements. Clay units may contain post-consumer
or post-industrial recycled content.]
2.2.1 Solid Clay or Shale Brick
NOTE: ASTM C 216 may be deleted for projects located where brick conforming
to ASTM C 62 provides aesthetic appearance that does not detract from the design,
is generally available and predominantly used in the area, and the specific
brick will blend with existing or adjacent architecture.
Specify facing brick only where aesthetic value is a prime consideration or
to match existing construction. See ASTM C 216 for conditions under which Grade
MW may be allowed.
If larger units, such as utility brick, are required, change the specified dimensions.
If nominal dimensions are used, they should be so noted. Consider the use of
closure or utility brick when it is architecturally acceptable, though not solid,
at least as a Contractor's option. The cost per square foot of wall is about
15 percent less for closure brick, 20 percent less for utility brick, than for
standard brick. Use paragraph titled "Closure or Utility Brick" below.
Solid clay or shale brick shall conform to [ASTM C 62] [ASTM C 216, Type [FBS] [FBA] [FBX]]. Brick size shall
be modular and the nominal size of the brick used shall be 92 mm 3-5/8 inches thick, 57 mm 2-1/4 inches high,
and 200 mm 8 inches long (nominal) or 100 mm thick, 68 mm high and 200 mm long (nominal) 4 inches thick, 2-2/3
inches high and 8 inches long (nominal). Minimum compressive strength of the brick shall be [_____] MPa psi.
2.2.2 Hollow Clay or Shale Brick
NOTE: For exposed exterior and interior masonry, HBX has narrow color variation
and high degree of mechanical perfection. Use HBS where greater variation is
allowed. For architectural effects resulting from nonuniformity in size, color,
and texture, use HBA. Use HBB where color and texture are not a consideration
and a greater variation in size is permitted.
Hollow clay or shale brick shall conform to ASTM C 652, Type [HBS] [HBX] [HBA] [HBB]. Brick size shall be modular
and the nominal size of the brick used shall be [_____] mm inches thick, [_____] mm inches high, and [_____]
mm inches long. Where vertical reinforcement is shown in hollow brick, the minimum cell dimension shall be 64
mm 2-1/2 inches and the units shall be designed to provide precise vertical alignment of the cells. Minimum
compressive strength of the brick shall be [_____] MPa psi.
2.2.3 Sand-Lime Brick
NOTE: Where all sand-lime brick is interior, Grade MW may be specified as an
option to Grade SW.
ASTM C 73, Grade SW, approximately 92 mm thick, 57 mm high, 200 mm long (nominal) 3 5/8 inches thick, 2 1/4 inches
high, and 8 inches long (nominal) or nominal modular, with smooth surfaces and natural color.
2.2.4 Refractory Brick
ASTM C 27, low-duty type, [_____] mm inches thick, [_____] mm inches high, and [_____] mm inches long.
2.2.5 Closure or Utility Brick
ASTM C 216, Grade SW, Type FBS, [92 mm thick, 92 mm high, and 200 mm long (closure) 3 5/8 inches thick, 3 5/8
inches high, and 8 inches long (closure)] [or] [nominally 100 mm thick, 100 mm high, and 305 mm long (utility)
4 inches thick, 4 inches high, and 12 inches long (utility)]. [Closure] [or] [Utility] brick may be used at
the option of the Contractor, provided that changes necessitated by the use of such brick shall be the responsibility
of the Contractor. Color, texture, and range of brick shall match the brick [on display at [_____]] [indicated].
2.2.6 Adobe Brick
NOTE: Adobe shall meet accepted industry standards at a minimum. Determine
standards for reliable products and include in this paragraph.
[_____] mm inches thick, [_____] mm inches high, and [_____] mm inches long.
2.2.6.1 Traditional Adobe
Protect traditional adobe from water penetration by the application of adobe mud plaster, lime plaster, cement-
or lime-cement stucco and wide roof overhangs.
2.2.6.2 Semi-Stabilized Adobe
Semi-stabilized adobe shall contain 3 percent asphalt emulsion or portland cement by weight, or as prescribed
by local soil conditions and codes. Protect from water penetration by the application of adobe mud plaster,
lime plaster, cement- or lime-cement stucco and wide eaves.
2.2.6.3 Fully Stabilized Adobe
Fully stabilized adobe shall contain 5 percent asphalt emulsion or portland cement by weight, or as prescribed
by local soil conditions and codes.
2.3 CONCRETE BRICK
NOTE: Grade N is used for high strength and resistance to moisture penetration.
Grade S is used for lesser strength and moisture resistance. Grade N units
are for general use and may be exposed to weather. Split face brick (solid
concrete facing units), where required by design, should be added to this paragraph.
A particular color and texture may be specified when locally available and competitively
priced. Sizes may be specified for brick or split face brick where required
by the design.
Concrete brick shall conform to ASTM C 55, Grade [N] [S]. Concrete brick may be used where necessary for filling
out in concrete masonry unit construction.
2.4 SALVAGED BRICK
NOTE: Use of salvaged/recovered materials contributes to the following LEED
credit: MR3. Include submittal if pursuing this LEED credit, and coordinate
with Section 01 33 29 LEED(tm) DOCUMENTATION.
Include bracketed wording if bricks will be in structures used for children
or residences. Indicate on drawings locations where salvaged brick is acceptable.
Use [lead-free] salvaged bricks and other masonry units in place of new bricks or masonry units as indicated.
[Bricks salvaged from foundries or industrial buildings shall be washed with appropriate metal-dust removing
cleaner.] When using salvaged brick, select exterior face bricks from salvaged exterior face bricks. Bricks
shall meet standards of new bricks otherwise used in application, and shall be cleaned of all mortar prior to
use. Place exterior face towards the exterior.
2.5 CONCRETE MASONRY UNITS (CMU)
NOTE: Three weight classifications are included in ASTM C 90. It is important
that the weight classification desired be designated. If structural design
requires an f'm greater than 10 MPa (1500 psi), or if the requirement in subpart
d. of paragraph entitled "Prism Tests," is specified greater than 10 MPa (1500
psi) that must be indicated here by adding an exception which states the f'm.
Low alkali cement should be specified for use in CMU if efflorescence caused
by the use of available cement is a problem. If efflorescence is not a problem
edit last sentence.
A lightweight high performance CMU has been developed by USACERL. This unit
provides equivalent performance to a standard normal weight CMU, yet weighs
only 8.5 kg (19 pounds). This CMU does not meet a strict interpretation of
the ASTM C 90 requirements and may require a variance from local building officials.
Contact USACERL for supporting technical information.
Specify lightweight aggregate where required for structural or "U" value purposes.
Coordinate with structural and mechanical designers. Specify only normal weight
aggregate for single-wythe, ungrouted, exterior walls. For PACNAVFACENGCOM
projects, that conform to ASTM C 55, specify Brick. Otherwise, light or normal
weight aggregate should be optional with the Contractor, including single wythe,
grouted walls.
For single-wythe, concrete masonry unit exterior walls, specify water-repellant
admixture for both the masonry units and the mortar. This is a regional requirement
which shall be used, when applicable, for SOUTHNAVFACENGCOM projects; when appropriate,
the requirements may be used for projects in other areas. Use only with ASTM
C 744 masonry units.
Designer must verify that products meeting the indicated minimum recycled content
are available, preferably from at least three sources, to ensure adequate competition.
If not, write in suitable recycled content values that reflect availability
and competition. Use second option if Contractor is choosing recycled content
products in accordance with Section 01 33 29 LEED(tm) DOCUMENTATION.
Cement shall have a low alkali content and be of one brand. [Units shall contain a minimum of [5] [10] [_____]
percent post-consumer recycled content, or a minimum of [20] [40] [_____] percent post-industrial recycled content.][See
Section 01 33 29 LEED(tm) DOCUMENTATION for cumulative total recycled content requirements. Units may contain
post-consumer or post-industrial recycled content.] Units shall be of modular dimensions and air, water, or
steam cured. [Surfaces of units which are to be plastered or stuccoed shall be sufficiently rough to provide
bond]; [elsewhere,] [exposed surfaces of units shall be smooth and of uniform texture]. [Exterior concrete masonry
units shall have water-repellant admixture added during manufacture.]
a. Hollow Load-Bearing Units: ASTM C 90, made with lightweight [or medium weight] [or normal weight]
aggregate. Provide load-bearing units for exterior walls, foundation walls, load-bearing walls, and
shear walls.
b. Hollow Non-Load-Bearing Units: ASTM C 129, made with lightweight [or medium weight] [or normal weight]
aggregate. Load-bearing units may be provided in lieu of non-load-bearing units.
c. Solid Load-Bearing Units: ASTM C 90, lightweight [or medium weight] [or normal weight] units. Provide
solid units [for masonry bearing under structural framing members] [as indicated].
2.5.1 Aggregates
NOTE: Where sufficient evidence based on previous construction experience indicates
concrete masonry units manufactured from aggregate from a specific source may
be subject to excessive popouts and/or staining, contract specifications may
be written to exclude such aggregate.
Lightweight aggregates and blends of lightweight and heavier aggregates in proportions used in producing the
units, shall comply with the following requirements when tested for stain-producing iron compounds in accordance
with ASTM C 641: by visual classification method, the iron stain deposited on the filter paper shall not exceed
the "light stain" classification. Use industrial waste by-products (air-cooled slag, cinders, or bottom ash),
ground waste glass and concrete, granulated slag, and expanded slag in aggregates. Slag shall comply with ASTM C 989
; Grade [80] [100] [120].
2.5.2 Kinds and Shapes
NOTE: Bullnose units will be specified only in cases where sharp corners are
considered objectionable, such as in heavy traffic areas. If bullnose units
are specified, the locations of use will be detailed on the drawings and/or
listed in this paragraph.
Units shall be modular in size and shall include closer, jamb, header, lintel, and bond beam units and special
shapes and sizes to complete the work as indicated. In exposed interior masonry surfaces, units having a bullnose
shall be used for vertical external corners except at door, window, and louver jambs. Radius of the bullnose
shall be 25 mm 1 inch. Units used in exposed masonry surfaces in any one building shall have a uniform fine
to medium texture and a uniform color.
2.5.2.1 Architectural Units
NOTE: Where architectural units are used, local sources should be checked to
determine available shapes, sizes, patterns, and colors. Desired unit pattern
should be clearly shown on the drawings. Delete integral coloring if units
will be painted or if natural color is satisfactory. CMU veneer wythes should
be solid units to minimize trapping water which could lead to damage from freezing,
mildew, and efflorescence.
Units shall have patterned face shell. Face shell pattern shall be [fluted] [vertical scored] [split ribbed]
[_____]. Units shall be integrally colored during manufacture. Color shall be [_____]. Patterned face shell
shall be properly aligned in the completed wall.
2.5.2.2 Patterned, Decorative Screen Units
NOTE: Manufacturer's catalogs will be consulted for patterned units locally
available. Optional designs of patterned units will be shown as necessary for
competitive bidding.
Concrete masonry units conforming to applicable requirements of ASTM C 129 are
suitable for interior nonload-bearing screens, and may be specified where required.
Patterned, decorative screen units shall conform to the applicable requirements of [ASTM C 90] [ASTM C 129].
Units shall have uniform through-the-wall pattern, color, and texture.
2.5.3 Fire-Rated CMU
NOTE: The thickness of fire-rated walls as well as the required fire rating
will be indicated on the drawings. Such walls will be shown as continuous from
floor to deck above. Sections and details of these walls will clearly indicate
the extent of such walls. Solid grouted concrete and concrete brick masonry
150 mm (6 inches) or greater in thickness will be considered a 4-hour fire-rated
wall regardless of aggregate type.
Concrete masonry units used in fire-rated construction shown on the drawings shall be of minimum equivalent thickness
for the fire rating indicated and the corresponding type of aggregates indicated in TABLE I. Units containing
more than one of the aggregates listed in TABLE I will be rated on the aggregate requiring the greater minimum
equivalent thickness to produce the required fire rating. Construction shall conform to ASTM E 119.
TABLE I
FIRE-RATED CONCRETE MASONRY UNITS
See note (a) below
Minimum equivalent thickness in
mm (inches) for fire rating of:
Aggregate Type 4 hours 3 hours 2 hours
________________ _______ _______ _______
Pumice 120 100 75
Expanded slag 130 110 85
Expanded clay, shale, 145 120 95
or slate
Limestone, scoria, cinders 150 130 100
or unexpanded slag
Calcareous gravel 160 135 105
Siliceous gravel 170 145 115
TABLE I
FIRE-RATED CONCRETE MASONRY UNITS
See note (a) below
Minimum equivalent thickness
inches for fire rating of:
Aggregate Type 4 hours 3 hours 2 hours
______________ _______ _______ _______
Pumice 4.7 4.0 3.0
Expanded slag 5.0 4.2 3.3
Expanded clay, shale, 5.7 4.8 3.7
or slate
Limestone, scoria, cinders 5.9 5.0 4.0
or unexpanded slag
Calcareous gravel 6.2 5.3 4.2
Siliceous gravel 6.7 5.7 4.5
Minimum equivalent thickness shall equal net volume as determined in conformance with ASTM C 140 divided by the
product of the actual length and height of the face shell of the unit in mm inches. Where walls are to receive
plaster or be faced with brick, or otherwise form an assembly; the thickness of plaster or brick or other material
in the assembly will be included in determining the equivalent thickness.
2.6 COMPRESSED EARTH BLOCK
NOTE: Compressed earth block is made by pressing damp adobe earth into steel
molds using a high-pressure, hand-operated or hydraulic press.
Compressed earth block shall meet accepted industry standards at a minimum.
Determine standards for reliable products and include in this paragraph.
Earth may be stabilized by adding 2 to 5 percent portland cement by weight for semi-stabilized block, and 5 to
10 percent for fully stabilized block; use of other stabilizing admixtures, and their proportions, shall be prescribed
by local soil conditions and codes. [250][_____] mm [10][_____] inches thick, [100][_____] mm [4][_____] inches
high, and [356][_____] mm [14][_____] inches long, 17 to 19 kg 38 to 40 pounds, using an average of 7,585 kPa
1,100 psi for unstabilized and 20,685 kPa 3,000 psi for stabilized.
2.7 PRECAST CONCRETE ITEMS
Trim, lintels, copings, splashblocks and door sills shall be factory-made units from a plant regularly engaged
in producing precast concrete units. Unless otherwise indicated, concrete shall be [28] [20] MPa [4,000] [3000]
psi minimum conforming to Section [03 31 00.00 10 CAST-IN-PLACE STRUCTURAL CONCRETE][03 30 00 CAST-IN-PLACE CONCRETE]
using 13 mm 1/2 inch to No. 4 nominal-size coarse aggregate, and minimum reinforcement shall be the reinforcement
required for handling of the units. Clearance of 19 mm 3/4 inch shall be maintained between reinforcement and
faces of units. Unless precast-concrete items have been subjected during manufacture to saturated-steam pressure
of at least 827 kPa 120 psi for at least 5 hours, the items, after casting, shall be either damp-cured for 24
hours or steam-cured and shall then be aged under cover for 28 days or longer. Cast-concrete members weighing
over 35 kg 80 pounds shall have built-in loops of galvanized wire or other approved provisions for lifting and
anchoring. Units shall have beds and joints at right angles to the face, with sharp true arises and shall be
cast with drip grooves on the underside where units overhang walls. Exposed-to-view surfaces shall be free of
surface voids, spalls, cracks, and chipped or broken edges. Precast units exposed-to-view shall be of uniform
appearance and color. Unless otherwise specified, units shall have a smooth dense finish. Prior to use, each
item shall be wetted and inspected for crazing. Items showing evidence of dusting, spalling, crazing, or having
surfaces treated with a protective coating will be rejected.
2.7.1 Lintels
NOTE: Insert strength of concrete; precast lintels usually range from 17 to
25 MPa (2500 to 3500 psi).
Precast lintels, unless otherwise shown, shall be of a thickness equal to the wall and reinforced with two No.
4 bars for the full length. Top of lintels shall be labeled "TOP" or otherwise identified and each lintel shall
be clearly marked to show location in the structure. In reinforced masonry, lintels shall conform to ACI 318M
ACI 318 for flexural and shear strength and shall have at least 200 mm 8 inches bearing at each end. Concrete
shall have a minimum 28 day compressive strength of [_____] MPa psi using 13 mm 1/2 inch to No. 4 nominal-size
coarse aggregate. Reinforcement shall conform to ASTM A 615/A 615M Grade 400 MPa 60,000 psi. Limit lintel deflection
due to dead plus live load to L/600 or 7 mm 0.3 inches. Provide top and bottom bars for lintels over 900 mm
36 inches in length.
2.7.2 Sills and Copings
Sills and copings shall be cast with washes. Sills for windows having mullions shall be cast in sections with
head joints at mullions and a 6 mm 1/4 inch allowance for mortar joints. The ends of sills, except a 19 mm 3/4
inch wide margin at exposed surfaces, shall be roughened for bond. Treads of door sills shall have rounded nosings.
[Reinforce sills with not less than two No. 15 No. 4 bars.]
2.7.3 Splash Blocks
Splash blocks shall be as detailed. Reinforcement shall be the manufacturer's standard.
2.7.4 Flue Linings and Thimbles
ASTM C 315, free from fractures. Sizes and shapes shall be as indicated.
2.8 STONE ITEMS
NOTE: The stone specified herein is for structures requiring a limited quantity
of cut stone. Where previous experience indicates difficulty in obtaining precast
concrete trim of the specified quality, stone may be specified as a Contractor's
option.
Stone for trim, sills, lintels, and copings shall be limestone, sandstone, or granite, and shall be cut to the
design shown. Sandstone shall be standard grade, buff, gray, or buff brown, with a smooth finish free from clay
pits and tool marks. Granite shall be a good commercial grade building granite of medium or moderately coarse
grain, and a light or medium gray or light pink color, with a smooth machine finish on washes, 4-cut finish on
treads, and 6-cut or equivalent machine finish on other exposed surfaces. Limestone shall be standard buff limestone
with a smooth machine finish free from tool marks. Lintels, except when supported by a steel member, shall be
100 mm 4 inches or more thick from face to back edge and of the depth required to support the masonry over the
opening. Stone shall have beds and joints at right angles to the face, with sharp, true arises. Copings and
sills shall be provided with washes, and where overhanging the walls, shall have drips cut on the underside.
2.9 MORTAR FOR STRUCTURAL MASONRY
NOTE: The defaults for mortar and grout materials in ASTM C 270 and ASTM C
476 are alright for general construction. Specify Type III portland cement
for cold weather construction, Type II for moderate sulfate resistance. The
blended cements make a gray mortar; specify portland cement mortar or masonry
cement if white or colored mortar is necessary. Use only Type S for exterior
walls and M below ground. Do not use Type O in areas of moderate or high seismic
activity. Do not use Type N in areas of high seismic activity.
A, added to Type designation, i.e. IIA, means air-entrained. Use this for exterior
mortar in severe climates, but do not use for grout.
ASTM C 270 TABLE 2 Property Specification Requirements
(For laboratory prepared mortar only)
Mortar Type Average Water Air Aggregate
Compressive Retention Content Ratio
Strength Min. Max. (Measured
at 28 Days Percent Percent in Damp, Loose
Min. MPa Condition)
Cement-lime M 17 75 12 Not less than
S 12 75 12 2 1/4 and
N 5 75 14* not more than
O 2 75 14* 3 1/2 times
the sum of the
Masonry cement M 17 75 ** separate
S 12 75 ** volumes of
N 5 75 ** cementitious
O 2 75 ** materials
* When structural reinforcement is incorporated in cement-lime
mortar, the maximum air content shall be 12 percent.
** When structural reinforcement is incorporated in masonry
cement mortar, the maximum air content shall be 18 percent.
Type N should be used only for non-load-bearing walls.
Approximate the f'm of the unit masonry. Mortars should
be slightly weaker than masonry units so that cracking
will occur in joints where easy to repair.
ASTM C 270 TABLE 2 Property Specification Requirements
(For laboratory prepared mortar only)
Mortar Type Average Water Air Aggregate
Compressive Retention Content Ratio
Strength Min. Max. (Measured in
at 28 Days Percent Percent in Damp, Loose
Min. psi Condition)
Cement-lime M 2500 75 12 Not less than
S 1800 75 12 2 1/4 and
N 750 75 14* not more than
O 350 75 14* 3 1/2 times
the sum of the
Masonry cement M 2500 75 ** separate
S 1800 75 ** volumes of
N 750 75 ** cementitious
O 350 75 ** materials
* When structural reinforcement is incorporated in cement-lime
mortar, the maximum air content shall be 12 percent.
** When structural reinforcement is incorporated in masonry
cement mortar, the maximum air content shall be 18 percent.
Type N should be used only for non-load-bearing walls.
Approximate the f'm of the unit masonry. Mortars should be
slightly weaker than masonry units so that cracking will
occur in joints where easy to repair.
ASTM C 270, Type [M] [N] [S]. Strength (f'm) as indicated. Test in accordance with ASTM C 780. [Use Type [I]
[II] [III] portland cement.] [Use Type [IS] [IP] [I(PM)] blended hydraulic cement.] [Use Masonry cement.] Do
not use admixtures containing chlorides. When structural reinforcement is incorporated, maximum air-content
shall be 12 percent in cement-lime mortar and 18 percent in masonry cement mortar. Use up to 40 percent Class
F fly ash with type IP cement in cement-lime mortar. Fly ash shall comply with ASTM C 593.
2.10 MASONRY MORTAR
NOTE: See ASTM C 270 for guidance in selecting mortar types. Use Type M when
masonry is in contact with earth and high degree of compressive strength is required.
Type S should be used for reinforced masonry and when high degree of compressive
strength or high degree of lateral load resistance is required. Type S mortar
provides worability, weather tightness, durability and corrosion protection,
and will be used for most work. For cavity wall construction, a high degree
of lateral load is defined as an 130 km/h (80 mph) wind.
Type N mortar generally provides improved workability and weather tightness;
it has lower strength, durability and corrosion protection than Type S. It
should be used for all general interior and exterior above grade masonry construction
including chimneys and parapets unless higher compressive strength or a high
degree of lateral load resistance is required. For SOUTHNAVFACENGCOM projects,
use only Type S mortar for exterior walls except use Type M mortar when masonry
is in contact with earth.
The proportions allowed by ASTM C 270 for cement-lime mortars can result in
properties that are essentially of another mortar type. Mortars proportioned
for high strength can lead to debonding between the mortar joint and the brick
resulting in reduced wall flexural capacity and increased water penetration
leading to efflorescence problems. Therefore the proportions for cement-lime
Types S and N mortars will be as shown below.
Mortar coloring may be specified as required by architectural design.
Low alkali cement should be specified for use in mortar if efflorescence caused
by the use of available cement is a problem.
Type M mortar shall conform to ASTM C 270 and shall be used for foundation walls [, basement walls,] [and piers].
Mortar Type [S] [N] shall conform to the proportion specification of ASTM C 270 except Type S cement-lime mortar
proportions shall be 1 part cement, 1/2 part lime and 4-1/2 parts aggregate; Type N cement-lime mortar proportions
shall be 1 part cement, 1 part lime and 6 parts aggregate. Type N or S mortar shall be used for non-load-bearing,
non-shear-wall interior masonry; [approved commercial fire clay mortar or refractory cement (calcium-aluminate)
mortar for fire brick and flue liners;] and Type S for remaining masonry work; except where higher compressive
strength is indicated on structural drawings. When masonry cement ASTM C 91 is used the maximum air content
shall be limited to 12 percent and performance equal to cement-lime mortar shall be verified. Verification of
masonry cement performance shall be based on ASTM C 780 and ASTM C 1072. Pointing mortar in showers and kitchens
shall contain ammonium stearate, or aluminum tri-stearate, or calcium stearate in an amount equal to 3 percent
by weight of cement used. Cement shall have a low alkali content and be of one brand. Aggregates shall be from
one source.
2.10.1 Admixtures for Masonry Mortar
NOTE: Admixtures may cause efflorescence and may adversely affect the strength
of the mix or the protection of embedded steel items.
In cold weather, a non-chloride based accelerating admixture may be used subject to approval. Accelerating admixture
shall be non-corrosive, shall contain less than 0.2 percent chlorides, and shall conform to ASTM C 494/C 494M
, Type C.
2.10.2 Colored Mortar
NOTE: Indicate on the drawings locations of colored mortar.
Mortar coloring shall be added to the mortar used for exposed masonry surfaces to produce a uniform color matching
[_____]. Quantity of pigment to cementitious content of the masonry cement shall not exceed [5][_____] by weight;
carbon black shall not exceed [1][_____] percent by weight. Quantity of pigment to cementitious content of cement-lime
mix shall not exceed [10][_____] percent by weight, carbon black no more than [2][_____] percent by weight.
Mortar coloring shall be chemically inert, of finely ground limeproof pigment, and furnished in accurately pre-measured
and packaged units that can be added to a measured amount of cement. Compressive strength of colored mortar
shall equal [_____].
2.10.3 Hydrated Lime and Alternates
NOTE: Lime alternates can increase spreadability.
Hydrated lime shall conform to ASTM C 207, Type [S][SA].
2.10.4 Cement
NOTE: Coal fly ash, slag, cenospheres, and silica fumes are EPA designated
products to be ingredients in cement. See Section 01 62 35 RECYCLED/RECOVERED
MATERIALS and include additive options unless designer determines that justification
for non-use exists.
Portland cement shall conform to ASTM C 150, Type I,[ IA,] II,[ IIA,] or III[, IIIA]. Masonry cement shall conform
to ASTM C 91, Type [N][S][M]. Containers shall bear complete instructions for proportioning and mixing to obtain
the required types of mortar. Incorporate to the maximum extent, without conflicting with other requirements
of this section, up to 40 percent fly ash, up to 70 percent slag, up to 10 percent cenospheres, and up to 10
percent silica fume. Additives shall conform to requirements in Section [03 30 00 CAST-IN-PLACE CONCRETE][
03 31 00.00 10 CAST-IN-PLACE STRUCTURAL CONCRETE].
2.10.5 Pre-Mixed Mortar
Pre-mixed mortar shall conform to ASTM C 1142, Type [RN] [RS] [RM].
2.10.6 Sand and Water
Sand shall conform to ASTM C 144. Water shall be clean, potable, and free from substances which could adversely
affect the mortar.
2.11 WATER-REPELLANT ADMIXTURE
NOTE: For single-wythe, concrete masonry unit exterior walls, specify water-repellant
admixture for both the masonry units and the mortar. This is a regional requirement
which shall be used, when applicable, for SOUTHNAVFACENGCOM projects; when appropriate,
the requirements may be used for projects in other areas. Use only with ASTM
C 744 masonry units.
Polymeric type formulated to reduce porosity and water transmission. Construct panels of masonry units conforming
to ASTM C 744 and mortar which contain the water-repellant admixture. When tested in accordance with ASTM C 1072
, such panels shall have flexural strength not less than that specified or indicated. When tested in accordance
with ASTM E 514, panels shall exhibit no water visible on back of test panel and no leaks through the panel after
24 hours, and not more than 25 percent of wall area shall be damp after 72 hours.
2.12 GROUT AND READY-MIXED GROUT
NOTE: Low alkali cement should be specified for use in grout if efflorescence
caused by the use of available cement is a problem.
For structural masonry, the following applies. The defaults for mortar and
grout materials in ASTM C 270 and ASTM C 476 are all right for general construction.
Specify Type III portland cement for cold weather construction, Type II for
moderate sulfate resistance. The blended cements make a gray mortar; specify
portland cement mortar or masonry cement if white or colored mortar is necessary.
Use only Type S for exterior walls and M below ground. Do not use Type O in
areas of moderate or high seismic activity. Do not use Type N in areas of high
seismic activity.
Choice of fine or coarse grout depends on width of grout space and pour height;
a table with this information is in ACI 530/530.1.
Grout shall conform to ASTM C 476, [fine] [coarse]. Cement used in grout shall have a low alkali content. Grout
slump shall be between 200 and [250] [280] mm 8 and [10] [11] inches. Minimum grout strength shall be 14 MPa
2000 psi in 28 days, as tested by ASTM C 1019. Grout shall be used subject to the limitations of Table III.
Proportions shall not be changed and materials with different physical or chemical characteristics shall not
be used in grout for the work unless additional evidence is furnished that the grout meets the specified requirements.
Ready-Mixed grout shall conform to ASTM C 94/C 94M.
2.12.1 Admixtures for Grout
NOTE: Admixtures, including air entrainment, may cause efflorescence and may
adversely affect the strength of the mix or the protection of embedded steel
items.
A grouting-aid admixture may be desirable when concrete masonry and clay brick
units are highly absorbent to reduce early water loss, promote bonding, and
produce slight expansion to help ensure complete filling of cavities.
In cold weather, a non-chloride based accelerating admixture may be used subject to approval; accelerating admixture
shall be non-corrosive, shall contain less than 0.2 percent chlorides, and shall conform to ASTM C 494/C 494M
, Type C. In general, air-entrainment, anti-freeze or chloride admixtures shall not be used except as approved
by the Contracting Officer.
2.12.2 Grout Barriers
Grout barriers for vertical cores shall consist of fine mesh wire, fiberglass, or expanded metal.
2.13 ANCHORS, TIES, AND BAR POSITIONERS
NOTE: By definition, ties are connections between masonry elements, anchors
connect masonry to the structure, and fasteners are for attachments to masonry.
The anchors and ties specified in this paragraph are primarily used to laterally
tie masonry veneer to backup elements. Anchors and ties not incorporated in
the design will be deleted. If special anchors or ties are required by the
design, they will be specified to meet the necessary requirements.
Wire ties, centering devices, and joint reinforcement are available with three
weights of zinc coating and are recommended for the following types of exposure:
Wt. of Coating in
Exposure Finish Gram Per Sq. Meter
for 9 ga wire
Joint reinforcement, ASTM A 641/A 641M 100
interior walls Class 1
Wire ties or anchors in ASTM A 641/A 641M 270
exterior, completely Class 3
embedded in mortar or grout
Wire ties or anchors in ASTM A 153/A 153M 540
exterior walls not Class B
completely embedded in mortar
or grout
Joint reinforcement in ASTM A 641/A 641M 540
exterior walls or interior Class B
walls exposed to moist
environments (e.g. natatoria
and food processing)
Wt. of Coating in
Exposure Finish Oz. Per Sq. Foot
for 9 ga wire
Joint reinforcement, ASTM A 641/A 641M .35
interior walls Class 1
Wire ties or anchors in ASTM A 641/A 641M .90
exterior, completely Class 3
embedded in mortar or grout
Wire ties or anchors in ASTM A 153/A 153M 1.80
exterior walls not Class B
completely embedded in mortar
or grout
Joint reinforcement in ASTM A 641/A 641M 1.80
exterior walls or interior Class B
walls exposed to moist
environments (e.g. natatoria
and food processing)
Finish Wt. of Coating
(sheets) Gram Per
Sq. Meter
Sheet metal ties or anchors ASTM A 153/A 153M 458
exposed to weather Class B-2
Sheet metal ties or anchors ASTM A 653/A 653M 180
completely embedded in Z180
mortar
Finish Wt. of Coating
(sheets) Oz. Per
Sq. Foot
Sheet metal ties or anchors ASTM A 153/A 153M 1.50
exposed to weather Class B-2
[Sheet metal ties or anchors ASTM A 653/A 653M .60
completely embedded in Class G60]
mortar
Anchors and ties shall be fabricated without drips or crimps and shall be zinc-coated in accordance with ASTM A 153/A 153M
, Class B-2. Steel wire used for anchors and ties shall be fabricated from steel wire conforming to ASTM A 82/A 82M
. Wire ties or anchors in exterior walls shall conform to ASTM A 641/A 641M. Joint reinforcement in interior
walls, and in exterior or interior walls exposed to moist environment shall conform to ASTM A 641/A 641M; coordinate
with paragraph JOINT REINFORCEMENT below. Anchors and ties shall be sized to provide a minimum of 16 mm 5/8
inch mortar cover from either face.
2.13.1 Wire Mesh Ties
NOTE: Wire mesh ties will only be used to tie 100 mm (4 inch) thick concrete
masonry unit partitions to other intersecting masonry partition walls.
Wire mesh for tying 100 mm 4 inch thick concrete masonry unit partitions to other intersecting masonry partitions
shall be 13 mm 1/2 inch mesh of minimum 16 gauge 16 gauge steel wire. Minimum lengths shall be not less than
300 mm 12 inches.
2.13.2 Wall Ties
NOTE: Wall ties will be specified to provide an option to the typically used
continuous joint reinforcement to anchor the outer wythe to the inner wythe
of anchored veneer construction. Vertical spacing will normally be 400 mm (16
inches) on center and horizontal spacing of the unit ties will normally be 600
mm (24 inches) on center.
For SOUTHNAVFACENGCOM projects, add to text: "Provide anchors and ties for cavity
walls with integral drip located in the cavity." Do not use corrugated metal
ties in cavity walls; they are very thin and prone to corrosion. These ties
are generally used in residential construction.
Z-shaped ties should only be specified when bonding walls constructed with solid
units (not less than 75 percent of the gross cross-sectional area being solid).
Rectangular ties may be used with either solid or hollow units.
Adjustable wall ties may be used in areas of low seismic activity when the design
wind speed is less than 160 km/hr (100 mph); designer must follow the guidance
provided in UFC 3-310-04 SEISMIC DESIGN FOR BUILDINGS for any seismic design.
Adjustable wall ties are normally used when constructing one wythe independent
of the other. The preferred method of construction, however, is to bring the
wythes up together. Delete the sentences pertaining to adjustable ties when
they are not permitted.
Wall ties shall be rectangular-shaped or Z-shaped fabricated of 5 mm 3/16 inch diameter zinc-coated steel wire.
Rectangular wall ties shall be no less than 100 mm 4 inches wide. Wall ties may also be of a continuous type
conforming to paragraph JOINT REINFORCEMENT. Adjustable type wall ties, if approved for use, shall consist of
two essentially U-shaped elements fabricated of 5 mm 3/16 inch diameter zinc-coated steel wire. Adjustable ties
shall be of the double pintle to eye type and shall allow a maximum of 13 mm 1/2 inch eccentricity between each
element of the tie. Play between pintle and eye opening shall be not more than 2 mm 1/16 inch. The pintle and
eye elements shall be formed so that both can be in the same plane.
2.13.3 Dovetail Anchors
Dovetail anchors shall be of the flexible wire type, 5 mm 3/16 inch diameter zinc-coated steel wire, triangular
shaped, and attached to a 12 gauge 12 gauge or heavier steel dovetail section. These anchors shall be used for
anchorage of veneer wythes or composite-wall facings extending over the face of concrete columns, beams, or walls.
Cells within vertical planes of these anchors shall be filled solid with grout for full height of walls or partitions,
or solid units may be used. Dovetail slots are specified in Section [03 31 00.00 10 CAST-IN-PLACE STRUCTURAL
CONCRETE][03 30 00 CAST-IN-PLACE CONCRETE].
2.13.4 Adjustable Anchors
NOTE: Adjustable anchors will be used to anchor masonry to structural steel
columns or beams. The fixed portion of the anchors (steel anchor rods) will
be welded to the structural steel member. In instances where standard anchors
are not available, such as when anchoring masonry to a steel beam that is offset
from the masonry wall line, anchors will be detailed on the drawings.
Adjustable anchors shall be 5 mm 3/16 inch diameter steel wire, triangular-shaped. Anchors attached to steel
shall be 8 mm 5/16 inch diameter steel bars placed to provide 2 mm 1/16 inch play between flexible anchors and
structural steel members. Spacers shall be welded to rods and columns. Equivalent welded-on steel anchor rods
or shapes standard with the flexible-anchor manufacturer may be furnished when approved. Welds shall be cleaned
and given one coat of zinc-rich touch up paint.
2.13.5 Bar Positioners
Bar positioners, used to prevent displacement of reinforcing bars during the course of construction, shall be
factory fabricated from 9 gauge steel wire or equivalent, and coated with a hot-dip galvanized finish. Not more
than one wire shall cross the cell.
2.14 JOINT REINFORCEMENT
NOTE: Location of horizontal joint reinforcement should be shown on the drawings.
Reinforcement will have one wire in each mortar bed. Truss-type joint reinforcement
will not be used. Adjustable joint reinforcement assemblies may be used in
certain types of construction where it is feasible to construct one wythe independent
of the other. If the type of design does not permit this type of construction,
delete the sentences pertaining to adjustable joint reinforcement assemblies.
Various combinations of wire sizes are available and are usually designated
as follows:
Long. wires Cross wires
Standard 3.8 mm 3.8 mm
Heavy Duty 4.8 mm 3.8 mm
Extra Heavy Duty 4.8 mm 4.8 mm
Long. wires Cross wires
Standard 9 gauge (0.1483 inch) 9 gauge
Heavy Duty 3/16 inch (0.1875 inch) 9 gauge
Extra Heavy Duty 3/16 inch 3/16 inch
Reinforcement made with 4.2 mm (8 gauge) wire is considered special and is not
available from all manufacturers.
Joint reinforcement shall be factory fabricated from steel wire conforming to ASTM A 82/A 82M, welded construction.
Tack welding will not be acceptable in reinforcement used for wall ties. Wire shall have zinc coating conforming
to ASTM A 153/A 153M, Class B-2. All wires shall be a minimum of [9] [_____] gauge. Reinforcement shall be
ladder type design, having one longitudinal wire in the mortar bed of each face shell for hollow units and one
wire for solid units. Joint reinforcement shall be placed a minimum of 16 mm 5/8 inch cover from either face.
The distance between crosswires shall not exceed 400 mm 16 inches. Joint reinforcement for straight runs shall
be furnished in flat sections not less than 3 m 10 feet long. Joint reinforcement shall be provided with factory
formed corners and intersections. If approved for use, joint reinforcement may be furnished with adjustable
wall tie features.
2.15 REINFORCING STEEL BARS AND RODS
Reinforcing steel bars and rods shall conform to ASTM A 615/A 615M, Grade 60.
2.16 CONTROL JOINT KEYS
NOTE: Control joint keys are generally not required vertically between the
floor line or grade to other floor lines or roofs and no shear transfer is required
across control joints. Delete paragraph when not required. Control joints
will be detailed on the drawings. When control joint keys are not required
by design, the control joint detail will show the head joint completely filled
with mortar for the width of the wythe; but joints will be flush, raked, or
raked and sealed as required.
Control joint keys shall be a factory fabricated solid section of natural or synthetic rubber (or combination
thereof) conforming to ASTM D 2000or polyvinyl chloride conforming to ASTM D 2287. The material shall be resistant
to oils and solvents. The control joint key shall be provided with a solid shear section not less than 16 mm
5/8 inch thick and 10 mm 3/8 inch thick flanges, with a tolerance of plus or minus 2 mm 1/16 inch. The control
joint key shall fit neatly, but without forcing, in masonry unit jamb sash grooves. The control joint key shall
be flexible at a temperature of minus 34 degrees C minus 30 degrees F after five hours exposure, and shall have
a durometer hardness of not less than 70 when tested in accordance with ASTM D 2240.
2.17 RIGID BOARD-TYPE INSULATION
NOTE: Insert the appropriate thickness and R-Value to be used for the insulation.
The total R-value for the insulation and the total thickness of the insulation
must be coordinated to fit the space provided within the wall cavity. The thickness
of the insulation must allow for not less than 19 mm (3/4 inch) air space between
the insulation and the facing veneer. This will limit the insulation thickness
to 50 mm (2 inches) in a 70 mm (2-3/4 inch) cavity space. If greater insulation
thickness is required the masonry wall must be designed to provide a larger
cavity.
To assure adequate competition, an R-value should be chosen that allows several
products to meet the specified thickness. The range of design R-values (in
IP units) for foam insulations given by ASHRAE is 5 to 7 per inch. Verify range
available from manufacturers. An aged R-value in SI units of 2 (11, in IP units)
can be readily achieved with 50 mm (2 inches) of insulation.
Cellular plastic insulations (polystyrene, polyurethane and polyisocyanurate)
are thermally efficient, however, certain precautions should be observed in
their use due to high smoke development and toxicity of the smoke generated
by the burning of these materials. Cellular plastic insulations should only
be used in anchored veneer masonry walls where the insulation is completely
isolated from the interior of the building by masonry, including all penetrations
of the interior wythe.
Provide rigid board-type insulation as specified in Section 07 21 13 BOARD AND BLOCK INSULATION.
2.18 EXPANSION-JOINT MATERIALS
NOTE: Using interior low-VOC products contributes to the following LEED credit:
EQ4. Include VOC submittal if pursuing this LEED credit, and coordinate with
Section 01 33 29 LEED(tm) DOCUMENTATION.
Backer rod and sealant shall be adequate to accommodate joint compression equal to 50 percent of the width of
the joint. The backer rod shall be compressible rod stock of polyethylene foam, polyurethane foam, butyl rubber
foam, or other flexible, nonabsorptive material as recommended by the sealant manufacturer. Sealant shall conform
to Section 07 92 00 JOINT SEALANTS, and shall be penetrating[ with a maximum volatile organic compound (VOC)
content of 600 grams/liter].
2.19 THROUGH WALL FLASHING
NOTE: Require flashing in exterior masonry walls, including single-wythe construction,
at all obstructions such as bond beams, sills, lintels, and concrete tie beams.
The wall design and detailing must conform to National Concrete Masonry Association
(NCMA) publications: TEK 13A, "Details for Building Dry Concrete Masonry Walls";
TEK 53, "Design of Concrete Masonry for Crack Control"; TEK 126, "Flashing Concrete
Masonry"; BIA Technical Notes 7 for water penetration, resistance; and BIA Technical
Notes 18A for crack control. Show locations and details on project drawings.
This is a regional requirement which shall be used, when applicable, for SOUTHNAVFACENGCOM
projects; when appropriate, the requirements may be used for projects in other areas.
Reinforced membrane flashing should only be an option for residential construction.
Do not use polyester film flashing on any other type construction projects.
Copper may stain masonry and deteriorate in high chloride environments.
Flashing shall be as specified in Section 07 60 00 FLASHING AND SHEET METAL. Provide one of the following types
[except that flashing indicated to terminate in reglets shall be metal or coated-metal flashing] [and] [except
that the material shall be one which is not adversely affected by dampproofing material.]
a. Coated-Copper Flashing: 0.2 kg 7 ounce, electrolytic copper sheet, uniformly coated on both sides
with acidproof, alkaliproof, elastic bituminous compound. Factory apply coating to a weight of not less
than 1.8 kg/square meter 6 ounces/square foot (approximately 0.9 kg/square meter 3 ounces/square foot
on each side).
b. Copper or Stainless Steel Flashing: Copper, ASTM B 370, minimum 450 kg 16 ounce weight; stainless
steel, ASTM A 167, Type 301, 302, 304, or 316, 4 mm 0.015 inch thick, No. 2D finish. Provide with factory-fabricated
deformations that mechanically bond flashing against horizontal movement in all directions. Deformations
shall consist of dimples, diagonal corrugations, or a combination of dimples and transverse corrugations.
[c. Reinforced Membrane Flashing: Polyester film core with a reinforcing fiberglass scrim bonded to
one side. The membrane shall be impervious to moisture, flexible, and not affected by caustic alkalis.
The material, after being exposed for not less than 1/2 hour to a temperature of 0 degrees C 32 degrees
F, shall show no cracking when, at that temperature, it is bent 180 degrees over a 2 mm 1/16 inch diameter
mandrel and then bent at the same point over the same size mandrel in the opposite direction 360 degrees.]
2.20 WEEP HOLE VENTILATORS
Weep hole ventilators shall be prefabricated aluminum, plastic or wood blocking sized to form the proper size
opening in head joints. Provide aluminum and plastic inserts with grill or screen-type openings designed to
allow the passage of moisture from cavities and to prevent the entrance or insects. Ventilators shall be sized
to match modular construction with a standard 10 mm 3/8 inch mortar joint.
PART 3 EXECUTION
3.1 PREPARATION
Prior to start of work, masonry inspector shall verify the applicable conditions as set forth in ACI 530/530.1
, inspection. The Contracting Officer will serve as inspector or will select a masonry inspector.
3.1.1 Protection
Ice or snow formed on the masonry bed shall be thawed by the application of heat. Heat shall be applied carefully
until the top surface of the masonry is dry to the touch. Sections of masonry deemed frozen and damaged shall
be removed before continuing construction of those sections.
a. Air Temperature 4 to 0 degrees C 40 to 32 Degrees F. Sand or mixing water shall be heated to produce
mortar temperatures between 4 and 49 degrees C 40 and 120 degrees F
b. Air Temperature 0 to minus 4 degrees C 32 to 25 Degrees F. Sand and mixing water shall be heated
to produce mortar temperatures between 4 and 49 degrees C 40 and 120 degrees F. Temperature of mortar
on boards shall be maintained above freezing.
c. Air Temperature minus 4 to minus 7 degrees C 25 to 20 Degrees F. Sand and mixing water shall be
heated to provide mortar temperatures between 4 and 49 degrees C 40 and 120 degrees F. Temperature of
mortar on boards shall be maintained above freezing. Sources of heat shall be used on both sides of
walls under construction. Windbreaks shall be employed when wind is in excess of 24 km/hour 15 mph.
d. Air Temperature minus 7 degrees C 20 Degrees F and below. Sand and mixing water shall be heated
to provide mortar temperatures between 4 and 49 degrees C 40 and 120 degrees F. Enclosure and auxiliary
heat shall be provided to maintain air temperature above 0 degrees C 32 degrees F. Temperature of units
when laid shall not be less than minus 7 degrees C 20 degrees F.
3.1.2 Completed Masonry and Masonry Not Being Worked On
a. Mean daily air temperature 4 to 0 degrees C 40 to 32 degrees F. Masonry shall be protected from
rain or snow for 24 hours by covering with weather-resistive membrane.
b. Mean daily air temperature 0 to minus 4 degrees C 32 to 25 degrees F. Masonry shall be completely
covered with weather-resistant membrane for 24 hours.
c. Mean Daily Air Temperature minus 4 to minus 7 degrees C 25 to 20 degrees F. Masonry shall be completely
covered with insulating blankets or equally protected for 24 hours.
d. Mean Daily Temperature minus 7 degrees C 20 degrees F and Below. Masonry temperature shall be maintained
above 0 degrees C 32 degrees F for 24 hours by enclosure and supplementary heat, by electric heating
blankets, infrared heat lamps, or other approved methods.
3.1.3 Stains
Protect exposed surfaces from mortar and other stains. When mortar joints are tooled, remove mortar from exposed
surfaces with fiber brushes and wooden paddles. Protect base of walls from splash stains by covering adjacent
ground with sand, sawdust, or polyethylene.
3.1.4 Loads
Do not apply uniform loads for at least 12 hours or concentrated loads for at least 72 hours after masonry is
constructed. Provide temporary bracing as required.
3.1.5 Surfaces
Surfaces on which masonry is to be placed shall be cleaned of laitance, dust, dirt, oil, organic matter, or other
foreign materials and shall be slightly roughened to provide a surface texture with a depth of at least 3 mm
1/8 inch. Sandblasting shall be used, if necessary, to remove laitance from pores and to expose the aggregate.
3.2 LAYING MASONRY UNITS
NOTE: Specify bond pattern for each type of masonry. Where more than one bond
pattern is required, the drawings should indicate the location and extent of
each bond pattern. Bond patterns for reinforced hollow masonry construction
should be such that cores of units will be in alignment vertically. Where stacked
bond is specified in reinforced hollow masonry, horizontal rebars shall be provided
at 600 mm (2 foot) intervals or horizontal joint reinforcement must be required
in every other horizontal joint to provide mechanical bond between adjacent
units. Veneers should be anchored at 300 mm (12 inches) on centers vertically
when stacked bond is used and 400 mm (16 inches) on centers vertically when
running bond is used. The use of stacked bond is discouraged and should only
be permitted for small wall areas to give an architectural feature, such as
for a building entrance detail.
a. Coordinate masonry work with the work of other trades to accommodate built-in items and to avoid
cutting and patching. Masonry units shall be laid in [running] [stacked] [the indicated] bond pattern.
Facing courses shall be level with back-up courses, unless the use of adjustable ties has been approved
in which case the tolerances shall be plus or minus 13 mm 1/2 inch. Each unit shall be adjusted to its
final position while mortar is still soft and plastic.
b. Units that have been disturbed after the mortar has stiffened shall be removed, cleaned, and relaid
with fresh mortar. Air spaces, cavities, chases, expansion joints, and spaces to be grouted shall be
kept free from mortar and other debris. Units used in exposed masonry surfaces shall be selected from
those having the least amount of chipped edges or other imperfections detracting from the appearance
of the finished work. Vertical joints shall be kept plumb.
c. Units being laid and surfaces to receive units shall be free of water film and frost. Solid units
shall be laid in a nonfurrowed full bed of mortar. Mortar for veneer wythes shall be beveled and sloped
toward the center of the wythe from the cavity side. Units shall be shoved into place so that the vertical
joints are tight. Vertical joints of brick and the vertical face shells of concrete masonry units, except
where indicated at control, expansion, and isolation joints, shall be completely filled with mortar.
Mortar will be permitted to protrude up to 13 mm 1/2 inch into the space or cells to be grouted. Means
shall be provided to prevent mortar from dropping into the space below.
d. In double wythe construction, the inner wythe may be brought up not more than 400 mm 16 inches ahead
of the outer wythe. Collar joints shall be filled with mortar or grout during the laying of the facing
wythe, and filling shall not lag the laying of the facing wythe by more than 200 mm 8 inches.
3.2.1 Forms and Shores
Provide bracing and scaffolding as required. Design bracing to resist wind pressure as required by local codes.
Forms and shores shall be sufficiently rigid to prevent deflections which may result in cracking or other damage
to supported masonry and sufficiently tight to prevent leakage of mortar and grout. Supporting forms and shores
shall not be removed in less than 10 days.
3.2.2 Reinforced Concrete Masonry Units Walls
NOTE: For single-wythe, concrete masonry unit exterior walls, specify water-repellant
admixture for both the masonry units and the mortar. This is a regional requirement
which shall be used, when applicable, for SOUTHNAVFACENGCOM projects; when appropriate,
the requirements may be used for projects in other areas. Use only with ASTM
C 744 masonry units.
Where vertical reinforcement occurs, fill cores solid with grout. Lay units in such a manner as to preserve
the unobstructed vertical continuity of cores to be filled. Embed the adjacent webs in mortar to prevent leakage
of grout. Remove mortar fins protruding from joints before placing grout. Minimum clear dimensions of vertical
cores shall be 50 by 75 mm 2 by 3 inches. Position reinforcing accurately as indicated before placing grout.
As masonry work progresses, secure vertical reinforcing in place at vertical intervals not to exceed 160 bar
diameters. Use puddling rod or vibrator to consolidate the grout. Minimum clear distance between masonry and
vertical reinforcement shall be not less than 13 mm 1/2 inch. Unless indicated or specified otherwise, form
splices by lapping bars not less than 40 bar diameters and wire tying them together.
3.2.3 Concrete Masonry Units
Units in piers, pilasters, columns, starting courses on footings, solid foundation walls, lintels, and beams,
and where cells are to be filled with grout shall be full bedded in mortar under both face shells and webs.
Other units shall be full bedded under both face shells. Head joints shall be filled solidly with mortar for
a distance in from the face of the unit not less than the thickness of the face shell. Foundation walls below
grade shall be grouted solid. Jamb units shall be of the shapes and sizes to conform with wall units. Solid
units may be incorporated in the masonry work where necessary to fill out at corners, gable slopes, and elsewhere
as approved. Double walls shall be stiffened at wall-mounted plumbing fixtures by use of strap anchors, two
above each fixture and two below each fixture, located to avoid pipe runs, and extending from center to center
of the double wall. Walls and partitions shall be adequately reinforced for support of wall-hung plumbing fixtures
when chair carriers are not specified.
3.2.4 Clay or Shale Brick Units
NOTE: Specify type of bond required, if other than running bond is desired.
Brick facing shall be laid with the better face exposed. Brick shall be laid in running bond with each course
bonded at corners, unless otherwise indicated. Molded brick shall be laid with the frog side down. Brick that
is cored, recessed, or has other deformations may be used in sills, treads, soldier courses, except where deformations
will be exposed to view. [Lay fire brick by dipping each brick in a soft mixture of fire clay and water and
then rubbing the brick into place with joints as thin as practicable or provide refractory mortar with joints
not more than 10 mm 3/8 inch thick.]
3.2.4.1 Wetting of Units
NOTE: If clay, shale brick, or hollow brick is specified, include wetting requirements
for units having an initial rate of absorption of more than 0.155 gm per minute
per square cm (1 gm per minute per square inch) (one gram per minute per square
inch) of bed surface.
Wetting of clay, shale brick, or hollow brick units having an initial rate of absorption of more than 0.155 gm
per minute per square cm 1 gram per minute per square inch of bed surface shall be in conformance with ASTM C 67
. The method of wetting shall ensure that each unit is nearly saturated but surface dry when laid. Test clay
or shale brick daily on the job, prior to laying, as follows: Using a wax pencil, draw a circle the size of
a quarter on five randomly selected bricks. Apply 20 drops of water with a medicine dropper to the surface within
the circle on each brick. If the average time that the water is completely absorbed in the five bricks is less
than 1-1/2 minutes, wet bricks represented by the five bricks tested.
3.2.4.2 Solid Units
Bed, head, and collar joints shall be completely filled with mortar.
3.2.4.3 Hollow Units
Hollow units shall be laid as specified for concrete masonry units.
3.2.4.4 Brick-Faced Walls
NOTE: Use the first bracketed option for masonry cavity wall construction.
Use the second bracketed option for cold-formed steel framing and brick veneer.
For brick-faced walls [bond the two wythes in every sixth brick course with continuous horizontal joint reinforcement.]
[bond brick in the pattern as indicated on the drawings.] Provide additional bonding ties spaced not more than
one meter 3 feet apart around the perimeter of and within 300 mm 12 inches of all openings.
a. Collar Joints: Fill collar joints solid with mortar as each course of brick is laid. Do not disturb
units in place.
b. Brick Sills: Lay brick on edge, slope, and project not less than 13 mm 1/2 inch beyond the face
of the wall to form a wash and drip. Fill all joints solidly with mortar and tool.
3.2.4.5 Cavity Walls
NOTE: Include weep holes and dampproofing requirements in geographic areas
where these are acceptable practices. Specify dampproofing for projects utilizing
concrete masonry unit interior wythe cavity walls. Now that masonry wall cavities
are usually at least half full of rigid board insulation, and the backup wythe
is usually complete before the brickwork is started, the wood strip method of
keeping the cavities clean is neither practicable nor effective. The specified
method for concrete masonry unit and brick cavity wall is effective, but may
be deleted if the specifier is reluctant to require it. Care must be taken
(1) to prevent damage to mortar joints, especially adjacent to the washout holes,
and (2) to prevent accumulation of water at the bottom of the wall. The cavities
must be inspected to verify that they are clean and functional.
For SOUTHNAVFACENGCOM projects, use second bracketed statement in the eighth
sentence.
Provide a continuous cavity as indicated. Securely tie the two wythes together with horizontal joint reinforcement.
Bevel mortar beds away from cavity to prevent projection into cavity when bricks are shoved in place. Keep cavities
clear and clean of mortar droppings. [At the bottom of cavity walls, in the course immediately above the through-wall
flashing, temporarily omit one brick every 1200 mm 4 feet. With a hose and clean water, wash all mortar droppings
and debris out of the cavity through the temporary openings at least twice each day masonry is laid, and more
often when required to keep the cavities clean. Fill in the openings with bricks and mortar after the wall is
complete and the cavity has been inspected and found clean.] Provide weep holes of open head joints spaced 600
mm 24 inches o.c. [wherever the cavity is interrupted] [at base of wall and vertical obstructions (e.g. lintels)].
[Cavity face of interior wythe shall be dampproofed in accordance with Section 07 11 13 BITUMINOUS DAMPPROOFING.]
3.2.4.6 Reinforced Brick Walls
Provide two wythes of brick separated by a [_____] mm inch wide continuous space filled with [grout] [bricks
"floated" in grout] and reinforced as indicated. Bevel mortar beds away from grout space to prevent projection
into grout space when bricks are shoved in place. Deeply furrowed bed joints will not be permitted. Lay exterior
wythe of brick to the height of each grout pour in advance of interior wythe. Clean grout space and set reinforcing
before laying interior wythe. Provide metal ties to prevent spreading of the wythes and to maintain vertical
alignment of walls. Position reinforcing as indicated. Wire vertical reinforcing securely in position as the
brickwork progresses. Use puddling rod or vibrator to consolidate the grout. The minimum clear distance between
parallel bars shall be the nominal diameter of the bars; the minimum clear distance between masonry and reinforcing
shall be 6 mm 1/4 inch. Unless indicated or specified otherwise, form splices by lapping bars not less than
40 bar diameters and wire tying them together. Stagger splices in adjacent horizontal bars.
3.2.4.7 Chimneys
NOTE: If a chimney wall is 200 mm (8 inches) or less in thickness, the space
between the flue liner and brickwork should be kept clean and clear to avoid
cracking the brickwork.
Construct chimneys of brick with clay flue linings of the sizes indicated. Extend flue linings from 300 mm 12
inches below the smoke inlet to 100 mm 4 inches above the chimney cap. Place thimbles as indicated, flush with
inside of or up to 25 mm one inch into the flue lining. Set linings in fire clay mortar or refractory mortar
and fill and smooth the joints on the inside. Set each section of flue lining before surrounding brickwork reaches
top of flue lining section below. Build brickwork around lining, and [fill the space] [leave a 25 mm one inch
airspace] between lining and brickwork [with grout]. [Seal top of airspace before installing chimney cap.]
Do not cut linings after they are installed in chimney. Unless indicated otherwise, provide a chimney cap of
air-entrained concrete. Slope cap to a minimum edge thickness of 50 mm 2 inches and reinforce with two rings
of No. 3 gage galvanized steel wire.
3.2.4.8 Brick Veneer
NOTE: Use this paragraph when cold-formed steel framing and brick veneer construction
is required.
Provide a continuous cavity as indicated. Install brick veneer after sheathing, masonry anchors, and flashing
have been installed to the cold-formed steel framing system. Care shall be provided to avoid damaging the moisture
barrier. Damaged moisture barrier and flashing shall be repaired or replaced before brick veneer is installed.
Means shall be provided to keep cavities clean and clear of mortar droppings.
3.2.5 Tolerances
Masonry shall be laid plumb, true to line, with courses level. Bond pattern shall be kept plumb throughout.
Corners shall be square unless noted otherwise. Except for walls constructed of prefaced concrete masonry units,
masonry shall be laid within the following tolerances (plus or minus unless otherwise noted):
TABLE II
TOLERANCES
Variation from the plumb in the lines
and surfaces of columns, walls and arises
____________________________________________________________
In adjacent masonry units 3 mm
In 3 m 6 mm
In 6 m 10 mm
In 12 m or more 13 mm
Variations from the plumb for external corners,
expansion joints, and other conspicuous lines
____________________________________________________________
In 6 m 6 mm
In 12 m or more 13 mm
Variations from the level for exposed lintels,
sills, parapets, horizontal grooves, and other
conspicuous lines
____________________________________________________________
In 6 m 6 mm
In 12 m or more 13 mm
Variation from level for bed joints and top
surfaces of bearing walls
____________________________________________________________
In 3 m 6 mm
In 12 m or more 13 mm
Variations from horizontal lines
____________________________________________________________
In 3 m 6 mm
In 6 m 10 mm
In 12 m or more 13 mm
Variations in cross sectional dimensions of
columns and in thickness of walls
____________________________________________________________
Minus 6 mm
Plus 13 mm
TABLE II
TOLERANCES
Variation from the plumb in the lines
and surfaces of columns, walls and arises
_______________________________________________________________
In adjacent masonry units 1/8 inch
In 10 feet 1/4 inch
In 20 feet 3/8 inch
In 40 feet or more 1/2 inch
Variations from the plumb for external corners,
expansion joints, and other conspicuous lines
_______________________________________________________________
In 20 feet 1/4 inch
In 40 feet or more 1/2 inch
Variations from the level for exposed lintels,
sills, parapets, horizontal grooves, and other
conspicuous lines
_______________________________________________________________
In 20 feet 1/4 inch
In 40 feet or more 1/2 inch
Variation from level for bed joints and top
surfaces of bearing walls
_______________________________________________________________
In 10 feet 1/4 inch
In 40 feet or more 1/2 inch
Variations from horizontal lines
_______________________________________________________________
In 10 feet 1/4 inch
In 20 feet 3/8 inch
In 40 feet or more 1/2 inch
Variations in cross sectional dimensions of
columns and in thickness of walls
_______________________________________________________________
Minus 1/4 inch
Plus 1/2 inch
3.2.6 Cutting and Fitting
Full units of the proper size shall be used wherever possible, in lieu of cut units. Cutting and fitting, including
that required to accommodate the work of others, shall be done by masonry mechanics using power masonry saws.
Concrete masonry units may be wet or dry cut. Wet cut units, before being placed in the work, shall be dried
to the same surface-dry appearance as uncut units being laid in the wall. Cut edges shall be clean, true and
sharp. Openings in the masonry shall be made carefully so that wall plates, cover plates or escutcheons required
by the installation will completely conceal the openings and will have bottoms parallel with the masonry bed
joints. Reinforced masonry lintels shall be provided above openings over 300 mm 12 inches wide for pipes, ducts,
cable trays, and other wall penetrations, unless steel sleeves are used.
3.2.7 Jointing
Joints shall be tooled when the mortar is thumbprint hard. Horizontal joints shall be tooled last. Joints shall
be brushed to remove all loose and excess mortar. Mortar joints shall be finished as follows:
3.2.7.1 Flush Joints
Joints in concealed masonry surfaces and joints at electrical outlet boxes in wet areas shall be flush cut.
Flush cut joints shall be made by cutting off the mortar flush with the face of the wall. Joints in unparged
masonry walls below grade shall be pointed tight. Flush joints for architectural units, such as fluted units,
shall completely fill both the head and bed joints.
3.2.7.2 Tooled Joints
NOTE: Joints in exterior masonry walls exposed to weather will be tooled with
an approved mortar joint, typically a slightly concave joint. Other joints
that are suitable for weathertight construction and may be considered for architectural
purposes are: Vee, Beaded, or Weathered types. Exposed to view or painted
interior masonry walls will also be tooled, typically with a slightly concaved
joint, but may also be tooled with other joint types as architecturally desired.
Joints in exposed exterior and interior masonry surfaces shall be tooled [slightly concave] [_____]. Joints
shall be tooled with a jointer slightly larger than the joint width so that complete contact is made along the
edges of the unit. Tooling shall be performed so that the mortar is compressed and the joint surface is sealed.
Jointer of sufficient length shall be used to obtain a straight and true mortar joint.
3.2.7.3 Door and Window Frame Joints
On the exposed interior side of exterior frames, joints between frames and abutting masonry walls shall be raked
to a depth of 10 mm 3/8 inch. On the exterior side of exterior frames, joints between frames and abutting masonry
walls shall be raked to a depth of 10 mm 3/8 inch.
3.2.8 Joint Widths
Joint widths shall be as follows:
3.2.8.1 Concrete Masonry Units
Concrete masonry units shall have 10 mm 3/8 inch joints, except for prefaced concrete masonry units.
3.2.8.2 Prefaced Concrete Masonry Units
Prefaced concrete masonry units shall have a joint width of 10 mm 3/8 inch wide on unfaced side and not less
than 5 mm 3/16 inch nor more than 6 mm 1/4 inch wide on prefaced side.
3.2.8.3 Brick
Brick joint widths shall be the difference between the actual and nominal dimensions of the brick in either height
or length. Brick expansion joint widths shall be as shown.
3.2.9 Embedded Items
Spaces around built-in items shall be filled with mortar. Openings around flush-mount electrical outlet boxes
in wet locations shall be pointed with mortar. Anchors, ties, wall plugs, accessories, flashing, pipe sleeves
and other items required to be built-in shall be embedded as the masonry work progresses. Anchors, ties and
joint reinforcement shall be fully embedded in the mortar. Cells receiving anchor bolts and cells of the first
course below bearing plates shall be filled with grout.
3.2.10 Unfinished Work
Unfinished work shall be stepped back for joining with new work. Toothing may be resorted to only when specifically
approved. Loose mortar shall be removed and the exposed joints shall be thoroughly cleaned before laying new
work.
3.2.11 Masonry Wall Intersections
NOTE: Details will be shown on the drawings which illustrate corners and intersections
of structural bond beam reinforcement and factory-formed joint reinforcement.
When joint reinforcement is not used, delete prefabricated corners or tee pieces.
Each course shall be masonry bonded at corners and elsewhere as shown. Masonry walls shall be anchored or tied
together at corners and intersections with bond beam reinforcement and prefabricated corner or tee pieces of
joint reinforcement as shown.
3.2.12 Partitions
NOTE: Walls and partitions which serve as fire walls or fire-rated walls will
be shown. Sections and details of these walls will clearly indicate the extent
of such walls. Non-structural masonry partition walls will not be tied in any
way to structural or exterior masonry walls. Isolation joints will be used
at these intersections. When 100 mm (4 inch) masonry partitions are not used,
delete reference to these units and their intersections.
Partitions shall be continuous from floor to underside of floor or roof deck where shown. Openings in firewalls
around joists or other structural members shall be filled as indicated or approved. Where suspended ceilings
on both sides of partitions are indicated, the partitions other than those shown to be continuous may be stopped
approximately 100 mm 4 inches above the ceiling level. An isolation joint shall be placed in the intersection
between partitions and structural or exterior walls as shown. Interior partitions having 100 mm 4 inch nominal
thick units shall be tied to intersecting partitions of 100 mm 4 inch units, 125 mm 5 inches into partitions
of 150 mm 6 inch units, and 175 7 inches into partitions of 200 mm 8 inch or thicker units. Cells within vertical
plane of ties shall be filled solid with grout for full height of partition or solid masonry units may be used.
Interior partitions having masonry walls over 100 mm 4 inches thick shall be tied together with joint reinforcement.
Partitions containing joint reinforcement shall be provided with prefabricated pieces at corners and intersections
or partitions.
3.3 COMPRESSED EARTH BLOCK
Install according to manufacturer instructions and accepted industry standards.
3.4 ANCHORED VENEER CONSTRUCTION
NOTE: Adjustable joint reinforcement assemblies may be used at locations of
low seismic activity where the design wind speed is less than 160 km/hr (100
mph); designer must follow the guidance provided in UFC 3-310-04 SEISMIC DESIGN
FOR BUILDINGS for any seismic design. Adjustable assemblies are normally used
when constructing one wythe independent of the other. If the design does not
permit this type of construction, delete the reference pertaining to adjustable
joint reinforcement assemblies. The preferred method of construction, however,
is to bring the wythes up together. Typically, continuous joint reinforcement
is used to tie the two wythes together as well as providing for shrinkage cracking
control. Continuous joint reinforcement, used as wall ties, will typically
be spaced not over 400 mm (16 inches) on center vertically. Spacing of joint
reinforcement will be shown on the contract drawings.
The inner and outer wythes shall be completely separated by a continuous airspace as shown on the drawings.
Both the inner and the outer wythes shall be laid up together except when adjustable joint reinforcement assemblies
are approved for use. When both wythes are not brought up together, through-wall flashings shall be protected
from damage until they are fully enclosed in the wall. The airspace between the wythes shall be kept clear and
free of mortar droppings by temporary wood strips laid on the wall ties and carefully lifted out before placing
the next row of ties. A coarse gravel or drainage material shall be placed behind the weep holes in the cavity
to a minimum depth of 100 mm 4 inches of coarse aggregate or 250 mm 10 inches of drainage material to keep mortar
droppings from plugging the weep holes.
3.5 WEEP HOLES
NOTE: Include weep holes and dampproofing requirements in geographic areas
where these are acceptable practices. Specify dampproofing in Division 7 of
the project specification for projects utilizing concrete masonry unit interior
wythe cavity walls. Now that masonry wall cavities are usually at least half
full of rigid board insulation, and the backup wythe is usually complete before
the brickwork is started, the wood strip method of keeping the cavities clean
is neither practicable nor effective. The specified method for concrete masonry
unit and brick cavity wall is effective, but may be deleted if the specifier
is reluctant to require it. Care must be taken (1) to prevent damage to mortar
joints, especially adjacent to the washout holes, and (2) to prevent accumulation
of water at the bottom of the wall. The cavities must be inspected to verify
that they are clean and functional. Weep holes and ventilators shall be located
to ensure that in severe weather, wind driven water does not enter and drain
into the interstitial space. Indicate acceptable locations on drawings.
For SOUTHNAVFACENGCOM projects, delete the second sentence and substitute with
the following: "Weep holes shall be full open head joints 600 mm (20 inches)
o.c. for brick faced walls and minimum 50 mm (2 inch) open head joints 900 mm
(32 inches) o.c. for concrete masonry unit construction."
Wherever through-wall flashing occurs, provide weep holes to drain flashing to exterior at acceptable locations
as indicated on drawings. Weep holes shall be [open head joints].[clear round holes not less than 6 mm 1/4 inch
in diameter] at 600 mm 24 inches o.c. Weep holes shall be provided not more than 600 mm 24 inches on centers
in mortar joints of the exterior wythe above wall flashing, over foundations, bond beams, and any other horizontal
interruptions of the cavity. Weep holes shall be perfectly horizontal or slightly canted downward to encourage
water drainage outward and not inward. [Weep holes shall be formed by placing short lengths of well-greased
No. 10, 8 mm 5/16 inch nominal diameter, braided cotton sash cord in the mortar and withdrawing the cords after
the wall has been completed.] [Weep holes shall be constructed using weep hole ventilators.] Other approved
methods may be used for providing weep holes. Weep holes shall be kept free of mortar and other obstructions.
3.6 COMPOSITE WALLS
Masonry wythes shall be tied together with joint reinforcement or with unit wall ties. Facing shall be anchored
to concrete backing with wire dovetail anchors set in slots built in the face of the concrete as specified in
Section [03 31 00.00 10 CAST-IN-PLACE STRUCTURAL CONCRETE][03 30 00 CAST-IN-PLACE CONCRETE]. The facing wythe
shall be anchored or tied to the backup at a maximum spacing of 400 mm 16 inches on center vertically and 600
mm 24 inches on center horizontally. Unit ties shall be spaced not over 600 mm 24 inches on centers horizontally,
in courses not over 400 mm 16 inches apart vertically, staggered in alternate courses. Ties shall be laid not
closer than 16 mm 5/8 inch to either masonry face. Ties shall not extend through control joints. Collar joints
between masonry facing and masonry backup shall be filled solidly with grout.
3.7 MORTAR MIX
Mortar shall be mixed in a mechanically operated mortar mixer for at least 3 minutes, but not more than 5 minutes.
Measurement of ingredients for mortar shall be by volume. Ingredients not in containers, such as sand, shall
be accurately measured by the use of measuring boxes. Water shall be mixed with the dry ingredients in sufficient
amount to provide a workable mixture which will adhere to the vertical surfaces of masonry units. Mortar that
has stiffened because of loss of water through evaporation shall be retempered by adding water to restore the
proper consistency and workability. Mortar that has reached its initial set or that has not been used within
[2.5] [_____] hours after mixing shall be discarded.
3.8 REINFORCING STEEL
Reinforcement shall be cleaned of loose, flaky rust, scale, grease, mortar, grout, or other coating which might
destroy or reduce its bond prior to placing grout. Bars with kinks or bends not shown on the drawings shall
not be used. Reinforcement shall be placed prior to grouting. Unless otherwise indicated, vertical wall reinforcement
shall extend to within 50 mm 2 inches of tops of walls.
3.8.1 Positioning Bars
NOTE: Positioning of bars will be shown on the drawings.
Vertical bars shall be accurately placed within the cells at the positions indicated on the drawings. A minimum
clearance of 13 mm 1/2 inch shall be maintained between the bars and masonry units. Minimum clearance between
parallel bars shall be one diameter of the reinforcement. Vertical reinforcing may be held in place using bar
positioners located near the ends of each bar and at intermediate intervals of not more than 192 diameters of
the reinforcement. Column and pilaster ties shall be wired in position around the vertical steel. Ties shall
be in contact with the vertical reinforcement and shall not be placed in horizontal bed joints.
3.8.2 Splices
Bars shall be lapped a minimum of 48 diameters of the reinforcement. Welded or mechanical connections shall
develop at least 125 percent of the specified yield strength of the reinforcement.
3.9 JOINT REINFORCEMENT INSTALLATION
NOTE: Location of horizontal joint reinforcement should be shown on the drawings
with the maximum vertical spacing normally being 400 mm (16 inches).
Joint reinforcement shall be installed at 400 mm 16 inches on center or as indicated. Reinforcement shall be
lapped not less than 150 mm 6 inches. Prefabricated sections shall be installed at corners and wall intersections.
The longitudinal wires of joint reinforcement shall be placed to provide not less than 16 mm 5/8 inch cover to
either face of the unit.
3.10 PLACING GROUT
Cells containing reinforcing bars shall be filled with grout. Hollow masonry units in walls or partitions supporting
plumbing, heating, or other mechanical fixtures, voids at door and window jambs, and other indicated spaces shall
be filled solid with grout. Cells under lintel bearings on each side of openings shall be filled solid with
grout for full height of openings. Walls below grade, lintels, and bond beams shall be filled solid with grout.
Units other than open end units may require grouting each course to preclude voids in the units. Grout not in
place within 1-1/2 hours after water is first added to the batch shall be discarded. Sufficient time shall be
allowed between grout lifts to preclude displacement or cracking of face shells of masonry units. If blowouts,
flowouts, misalignment, or cracking of face shells should occur during construction, the wall shall be torn down
and rebuilt.
3.10.1 Vertical Grout Barriers for Fully Grouted Walls
Grout barriers shall be provided not more than 10 m 30 feet apart, or as required, to limit the horizontal flow
of grout for each pour.
3.10.2 Horizontal Grout Barriers
Grout barriers shall be embedded in mortar below cells of hollow units receiving grout.
3.10.3 Grout Holes and Cleanouts
3.10.3.1 Grout Holes
Grouting holes shall be provided in slabs, spandrel beams, and other in-place overhead construction. Holes shall
be located over vertical reinforcing bars or as required to facilitate grout fill in bond beams. Additional openings
spaced not more than 400 mm 16 inches on centers shall be provided where grouting of all hollow unit masonry
is indicated. Openings shall not be less than 100 mm 4 inches in diameter or 75 by 100 mm 3 by 4 inches in horizontal
dimensions. Upon completion of grouting operations, grouting holes shall be plugged and finished to match surrounding
surfaces.
3.10.3.2 Cleanouts for Hollow Unit Masonry Construction
Cleanout holes shall be provided at the bottom of every pour in cores containing vertical reinforcement when
the height of the grout pour exceeds 1.5 m 5 feet. Where all cells are to be grouted, cleanout courses shall
be constructed using bond beam units in an inverted position to permit cleaning of all cells. Cleanout holes
shall be provided at a maximum spacing of 800 mm 32 inches where all cells are to be filled with grout. A new
series of cleanouts shall be established if grouting operations are stopped for more than 4 hours. Cleanouts
shall not be less than 75 by 100 mm 3 by 4 inch openings cut from one face shell. Manufacturer's standard cutout
units may be used at the Contractor's option. Cleanout holes shall not be closed until masonry work, reinforcement,
and final cleaning of the grout spaces have been completed and inspected. For walls which will be exposed to
view, cleanout holes shall be closed in an approved manner to match surrounding masonry.
3.10.3.3 Cleanouts for Solid Unit Masonry Construction
Cleanouts for construction of walls consisting of a grout filled cavity between solid masonry wythes shall be
provided at the bottom of every pour by omitting every other masonry unit from one wythe. A new series of cleanouts
shall be established if grouting operations are stopped for more than 4 hours. Cleanout holes shall not be plugged
until masonry work, reinforcement, and final cleaning of the grout spaces have been completed and inspected.
For walls which will be exposed to view, cleanout holes shall be closed in an approved manner to match surrounding
masonry.
3.10.4 Grouting Equipment
3.10.4.1 Grout Pumps
Pumping through aluminum tubes will not be permitted. Pumps shall be operated to produce a continuous stream
of grout without air pockets, segregation, or contamination. Upon completion of each day's pumping, waste materials
and debris shall be removed from the equipment, and disposed of outside the masonry.
3.10.4.2 Vibrators
Internal vibrators shall maintain a speed of not less than 5,000 impulses per minute when submerged in the grout.
At least one spare vibrator shall be maintained at the site at all times. Vibrators shall be applied at uniformly
spaced points not further apart than the visible effectiveness of the machine. Duration of vibration shall be
limited to time necessary to produce satisfactory consolidation without causing segregation.
3.10.5 Grout Placement
Masonry shall be laid to the top of a pour before placing grout. Grout shall not be placed in two-wythe solid
unit masonry cavity until mortar joints have set for at least 3 days during hot weather and 5 days during cold
damp weather. Grout shall not be placed in hollow unit masonry until mortar joints have set for at least 24
hours. Grout shall be placed using a hand bucket, concrete hopper, or grout pump to completely fill the grout
spaces without segregation of the aggregates. Vibrators shall not be inserted into lower pours that are in
a semi-solidified state. The height of grout pours and type of grout used shall be limited by the dimensions
of grout spaces as indicated in Table III. Low-lift grout methods may be used on pours up to and including 1.5
m 5 feet in height. High-lift grout methods shall be used on pours exceeding 1.5 m 5 feet in height.
3.10.5.1 Low-Lift Method
Grout shall be placed at a rate that will not cause displacement of the masonry due to hydrostatic pressure of
the grout. Mortar protruding more than 13 mm 1/2 inch into the grout space shall be removed before beginning
the grouting operation. Grout pours 300 mm 12 inches or less in height shall be consolidated by mechanical vibration
or by puddling. Grout pours over 300 mm 12 inches in height shall be consolidated by mechanical vibration and
reconsolidated by mechanical vibration after initial water loss and settlement has occurred. Vibrators shall
not be inserted into lower pours that are in a semi-solidified state. Low-lift grout shall be used subject to
the limitations of Table III.
3.10.5.2 High-Lift Method
Mortar droppings shall be cleaned from the bottom of the grout space and from reinforcing steel. Mortar protruding
more than 6 mm 1/4 inch into the grout space shall be removed by dislodging the projections with a rod or stick
as the work progresses. Reinforcing, bolts, and embedded connections shall be rigidly held in position before
grouting is started. CMU units shall not be pre-wetted. Grout, from the mixer to the point of deposit in the
grout space shall be placed as rapidly as practical by pumping and placing methods which will prevent segregation
of the mix and cause a minimum of grout splatter on reinforcing and masonry surfaces not being immediately encased
in the grout lift. The individual lifts of grout shall be limited to 1.2 m 4 feet in height. The first lift
of grout shall be placed to a uniform height within the pour section and vibrated thoroughly to fill all voids.
This first vibration shall follow immediately behind the pouring of the grout using an approved mechanical vibrator.
After a waiting period sufficient to permit the grout to become plastic, but before it has taken any set, the
succeeding lift shall be poured and vibrated 300 to 450 mm 12 to 18 inches into the preceding lift. If the placing
of the succeeding lift is going to be delayed beyond the period of workability of the preceding, each lift shall
be reconsolidated by reworking with a second vibrator as soon as the grout has taken its settlement shrinkage.
The waiting, pouring, and reconsolidation steps shall be repeated until the top of the pour is reached. The
top lift shall be reconsolidated after the required waiting period. The high-lift grouting of any section of
wall between vertical grout barriers shall be completed to the top of a pour in one working day unless a new
series of cleanout holes is established and the resulting horizontal construction joint cleaned. High-lift grout
shall be used subject to the limitations in Table III.
TABLE III
POUR HEIGHT AND TYPE OF GROUT FOR VARIOUS GROUT SPACE DIMENSIONS
Minimum Dimensions of the
Total Clear Areas Within Grout
Maximum Spaces and Cells (mm) (1,2)
Grout Pour
Height Grout Grouting Multiwythe Hollow-unit
(m) (4) Type Procedure Masonry (3) Masonry
____________ _______ ____________ ___________ _____________
0.3 Fine Low Lift 20 40 x 50
1.5 Fine Low Lift 50 50 x 75
2.4 Fine High Lift 50 50 x 75
3.6 Fine High Lift 65 65 x 75
7.3 Fine High Lift 75 75 x 75
0.3 Coarse Low Lift 40 40 x 75
1.5 Coarse Low Lift 50 65 x 75
2.4 Coarse High Lift 50 75 x 75
3.6 Coarse High Lift 65 75 x 75
7.3 Coarse High Lift 75 75 x 100
TABLE III
POUR HEIGHT AND TYPE OF GROUT FOR VARIOUS GROUT SPACE DIMENSIONS
Minimum Dimensions of the
Total Clear Areas Within Grout
Maximum Spaces and Cells (in.) (1,2)
Grout Pour
Height Grout Grouting Multiwythe Hollow-unit
(feet) (4) Type Procedure Masonry (3) Masonry
____________ _______ ____________ ___________ ______________
1 Fine Low Lift 3/4 1-1/2 x 2
5 Fine Low Lift 2 2 x 3
8 Fine High Lift 2 2 x 3
12 Fine High Lift 2-1/2 2-1/2 x 3
24 Fine High Lift 3 3 x 3
1 Coarse Low Lift 1-1/2 1-1/2 x 3
5 Coarse Low Lift 2 2-1/2 x 3
8 Coarse High Lift 2 3 x 3
12 Coarse High Lift 2-1/2 3 x 3
24 Coarse High Lift 3 3 x 4
Notes:
(1) The actual grout space or cell dimension shall be larger than the sum of the following items:
a) The required minimum dimensions of total clear areas given in the table above;
b) The width of any mortar projections within the space;
c) The horizontal projections of the diameters of the horizontal reinforcing bars within a cross
section of the grout space or cell.
(2) The minimum dimensions of the total clear areas shall be made up of one or more open areas, with
at least one area being 20 mm 3/4 inch or greater in width.
(3) For grouting spaces between masonry wythes.
(4) Where only cells of hollow masonry units containing reinforcement are grouted, the maximum height
of the pour shall not exceed the distance between horizontal bond beams.
3.11 BOND BEAMS
NOTE: Bond beams that are continuous over openings will be reinforced to serve
as lintels.
Bond beams shall be filled with grout and reinforced as indicated on the drawings. Grout barriers shall be installed
under bond beam units to retain the grout as required. Reinforcement shall be continuous, including around corners,
except through control joints or expansion joints, unless otherwise indicated on the drawings. Where splices
are required for continuity, reinforcement shall be lapped 48 bar diameters. A minimum clearance of 13 mm 1/2
inch shall be maintained between reinforcement and interior faces of units.
3.12 CONTROL JOINTS
NOTE: Control joints will be located and detailed on the drawings. When control
joint keys are required it is a Contractor's option to use either special control
joint units or sash jamb units with control joint keys. If one is preferred
over the other in the design, edit this paragraph accordingly and provide specific
details on the drawings. When control joint keys are not required, fill head
joints with mortar as detailed.
Control joints shall be provided as indicated and shall be constructed by using [mortar to fill the head joint]
[special control-joint units] [sash jamb units with control joint key] [open end stretcher units] in accordance
with the details shown on the drawings. Sash jamb units shall have a 19 by 19 mm 3/4 by 3/4 inch groove near
the center at end of each unit. The vertical mortar joint at control joint locations shall be continuous, including
through all bond beams. This shall be accomplished by utilizing half blocks in alternating courses on each side
of the joint. The control joint key shall be interrupted in courses containing continuous bond beam steel.
In single wythe exterior masonry walls, the exterior control joints shall be raked to a depth of 19 mm 3/4 inch
; backer rod and sealant shall be installed in accordance with Section 07 92 00 JOINT SEALANTS. Exposed interior
control joints shall be raked to a depth of 6 mm 1/4 inch. Concealed control joints shall be flush cut.
3.13 JOINTS SHOWN ON THE DRAWINGS
NOTE: Use a. or b. and delete the other; then add c. to the one selected.
a. Brick expansion joints
b. Concrete masonry veneer joints
c. will be located, detailed, and constructed as shown on the drawings. Keep joints free of mortar
and other debris.
3.14 SHELF ANGLES
Adjust shelf angles as required to keep the masonry level and at the proper elevation. Shelf angles shall be
galvanized and provided in sections not longer than 3 m 10 feet and installed with a 6 mm 1/4 inch gap between
sections. Shelf angles shall be mitered and welded at building corners with each angle not shorter than 1.2
m 4 feet, unless limited by wall configuration.
3.15 LINTELS
3.15.1 Masonry Lintels
Construct masonry lintels with lintel units filled solid with grout in all courses and reinforced with a minimum
of two No. 4 bars in the bottom course unless otherwise indicated on the drawings. Lintel reinforcement shall
extend beyond each side of masonry opening 40 bar diameters or 600 mm 24 inches, whichever is greater. Reinforcing
bars shall be supported in place prior to grouting and shall be located 13 mm 1/2 inch above the bottom inside
surface of the lintel unit.
3.15.2 Precast Concrete and Steel Lintels
Construct precast concrete and steel lintels as shown on the drawings. Lintels shall be set in a full bed of
mortar with faces plumb and true. Steel and precast lintels shall have a minimum bearing length of 200 mm 8
inches unless otherwise indicated on the drawings.
3.16 SILLS AND COPINGS
Sills and copings shall be set in a full bed of mortar with faces plumb and true.
3.17 ANCHORAGE TO CONCRETE AND STRUCTURAL STEEL
NOTE: If spacing of anchors varies from that specified, edit these paragraphs
accordingly.
3.17.1 Anchorage to Concrete
Anchorage of masonry to the face of concrete columns, beams, or walls shall be with dovetail anchors spaced not
over 400 mm 16 inches on centers vertically and 600 mm 24 inches on center horizontally.
3.17.2 Anchorage to Structural Steel
Masonry shall be anchored to vertical structural steel framing with adjustable steel wire anchors spaced not
over 400 mm 16 inches on centers vertically, and if applicable, not over 600 mm 24 inches on centers horizontally.
3.18 PARGING
NOTE: If parging is not required, or if other types of dampproofing are in
the project, this paragraph will be deleted.
The outside face of below-grade exterior concrete-masonry unit walls enclosing usable rooms and spaces, except
crawl spaces, shall be parged with type S mortar. Parging shall not be less than 13 mm 1/2 inch thick troweled
to a smooth dense surface so as to provide a continuous unbroken shield from top of footings to a line 150 mm
6 inches below adjacent finish grade, unless otherwise indicated. Parging shall be coved at junction of wall
and footing. Parging shall be damp-cured for 48 hours or more before backfilling. Parging shall be protected
from freezing temperatures until hardened.
3.19 INSULATION
Anchored veneer walls shall be insulated, where shown, by installing board-type insulation on the cavity side
of the inner wythe. Board type insulation shall be applied directly to the masonry or thru-wall flashing with
adhesive. Insulation shall be neatly fitted between obstructions without impaling of insulation on ties or
anchors. The insulation shall be applied in parallel courses with vertical joints breaking midway over the course
below and shall be applied in moderate contact with adjoining units without forcing, and shall be cut to fit
neatly against adjoining surfaces.
3.20 SPLASH BLOCKS
Splash blocks shall be located as shown.
3.21 POINTING AND CLEANING
After mortar joints have attained their initial set, but prior to hardening, completely remove mortar and grout
daubs or splashings from masonry-unit surfaces that will be exposed or painted. Before completion of the work,
defects in joints of masonry to be exposed or painted shall be raked out as necessary, filled with mortar, and
tooled to match existing joints. Immediately after grout work is completed, scum and stains which have percolated
through the masonry work shall be removed using a high pressure stream of water and a stiff bristled brush.
Masonry surfaces shall not be cleaned, other than removing excess surface mortar, until mortar in joints has
hardened. Masonry surfaces shall be left clean, free of mortar daubs, dirt, stain, and discoloration, including
scum from cleaning operations, and with tight mortar joints throughout. Metal tools and metal brushes shall
not be used for cleaning.
3.21.1 Dry-Brushing
NOTE: Use a. or b. and delete the other; then add c. to the one selected.
a. Exposed concrete masonry unit
b. Exposed concrete brick surfaces
c. shall be dry-brushed at the end of each day's work and after any required pointing, using stiff-fiber
bristled brushes.
3.21.2 Clay or Shale Brick Surfaces
Exposed clay or shale brick masonry surfaces shall be cleaned as necessary to obtain surfaces free of stain,
dirt, mortar and grout daubs, efflorescence, and discoloration or scum from cleaning operations. After cleaning,
examine the sample panel of similar material for discoloration or stain as a result of cleaning. If the sample
panel is discolored or stained, change the method of cleaning to ensure that the masonry surfaces in the structure
will not be adversely affected. The exposed masonry surfaces shall be water-soaked and then cleaned with a solution
proportioned 30 mL 1/2 cup trisodium phosphate and 30 mL 1/2 cup laundry detergent to 1 L one gallon of water
or cleaned with a proprietary masonry cleaning agent specifically recommended for the color and texture by the
clay products manufacturer. The solution shall be applied with stiff fiber brushes, followed immediately by
thorough rinsing with clean water. Proprietary cleaning agents shall be used in conformance with the cleaning
product manufacturer's printed recommendations. Efflorescence shall be removed in conformance with the brick
manufacturer's recommendations.
3.22 BEARING PLATES
NOTE: The bearing details must be shown on the drawings. The thermal effects
must be considered for steel beams bearing on masonry to prevent cracking of
masonry walls due to thermal expansion of steel framing members.
Set bearing plates for beams, joists, joist girders and similar structural members to the proper line and elevation
with damp-pack bedding mortar, except where non-shrink grout is indicated. Bedding mortar and non-shrink grout
shall be as specified in Section [03 31 00.00 10 CAST-IN-PLACE STRUCTURAL CONCRETE] [03 30 00 CAST-IN-PLACE CONCRETE].
3.23 PROTECTION
Protect facing materials against staining. Cover top of walls with nonstaining waterproof covering or membrane
when work is not in progress. Covering of the top of the unfinished walls shall continue until the wall is waterproofed
with a complete roof or parapet system. Covering shall extend a minimum of 600 mm 2 feet down on each side of
the wall and shall be held securely in place. Before starting or resuming, top surface of masonry in place shall
be cleaned of loose mortar and foreign material.
3.24 WASTE MANAGEMENT
NOTE: Diverting waste from the landfill contributes to the following LEED credit:
MR2. Coordinate with Section 02 42 00 CONSTRUCTION AND DEMOLITION WASTE MANAGEMENT.
Manage waste according to the Waste Management Plan and as follows. Minimize water used to wash mixing equipment.
Use trigger operated spray nozzles for water hoses.
3.24.1 Separate and Recycle Waste
Place materials defined as hazardous or toxic waste in designated containers. Fold up metal banding, flatten,
and place in designated area for recycling. Collect wood packing shims and pallets and place in designated area.
Use leftover mixed mortar as [retaining wall footing ballast] [cavity fill at grade] [underground utility pipe
kickers] [_____] where lower strength mortar meets the requirements for bulk fill. Separate masonry waste and
place in designated area for use as structural fill. Separate selected masonry waste and excess for landscape
uses, either whole or crushed as ground cover.
3.24.2 Take-Back Program
NOTE: Take-back programs refer to programs in which the product manufacturer
"takes-back" scrap material and/or packaging associated with its product.
Collect information from manufacturer for take-back program options. Set aside [masonry units, full and partial]
[scrap] [packaging] [_____] to be returned to manufacturer for recycling into new product. When such a service
is not available, local recyclers shall be sought after to reclaim the materials.
3.25 TEST REPORTS
3.25.1 Field Testing of Mortar
NOTE: Delete this paragraph for structures having 185 square meters (2,000
square feet) or less of wall area, including openings. See UFC 3-310-04 and
ASTM C 780 for evaluating mortar test results.
At least three specimens of mortar shall be taken each day. A layer of mortar 13 to 16 mm 1/2 to 5/8 inch thick
shall be spread on the masonry units and allowed to stand for one minute. The specimens shall then be prepared
and tested for compressive strength in accordance with ASTM C 780.
3.25.2 Field Testing of Grout
NOTE: Delete this paragraph for structures having 185 square meters (2,000
square feet) or less of wall area, including openings.
Field sampling and testing of grout shall be in accordance with the applicable provisions of ASTM C 1019. A
minimum of three specimens of grout per day shall be sampled and tested. Each specimen shall have a minimum
ultimate compressive strength of 13.8 MPa 2000 psi at 28 days.
3.25.3 Efflorescence Test
NOTE: Delete this paragraph in areas where efflorescence has not been a problem.
Efflorescence is generally the result of poor design and detailing. Properly
covered or flashed walls are generally free of efflorescence. Efflorescence
testing is generally not required.
Test brick, which will be exposed to weathering, for efflorescence. Schedule tests far enough in advance of
starting masonry work to permit retesting if necessary. Sampling and testing shall conform to the applicable
provisions of ASTM C 67. Units meeting the definition of "effloresced" will be subject to rejection.
3.25.4 Prism Tests
NOTE: Prism testing will only be required for structures requiring masonry
compressive strengths higher than the assumed value of 9.3 MPa (1350 psi).
Prism testing normally will not be required. Delete this paragraph when prism
testing is not required.
Perform at least one prism test sample for each 465 square meters 5,000 square feet of wall but not less than
three such samples shall be made for any building. Three prisms will be used in each sample. Prisms shall be
tested in accordance with ACI 530/530.1. Seven-day tests may be used provided the relationship between the 7-
and 28-day strengths of the masonry is established by the tests of the materials used. Compressive strength
shall not be less than [_____] MPa psi at 28 days. If the compressive strength of any prism falls below the
specified value by more than 3.5 MPa 500 psi, steps shall be taken to assure that the load-carrying capacity
of the structure is not jeopardized. If the likelihood of low-strength masonry is confirmed and computations
indicate that the load-carrying capacity may have been significantly reduced, tests of cores drilled, or prisms
sawed, from the area in question may be required. In such case, three specimens shall be taken for each prism
test more than 3.5 MPa 500 psi below the specified value. Masonry in the area in question shall be considered
structurally adequate if the average compressive strength of three specimens is equal to at least 85 percent
of the specified value, and if the compressive strength of no single specimen is less than 75 percent of the
specified value. Additional testing of specimens extracted from locations represented by erratic core or prism
strength test results will be permitted.