A/E Name / Issue Description
A/E Project No. / Month, 00, 0000
SECTION 09 22 23 – lath and plaster
PART 1 - GENERAL
1.01 RELATED DOCUMENTS
A. Drawings and general provisions of the Contract, including General Conditions and Division 01 Specification Sections, apply to this Section.
B. Specifications throughout all Divisions of the Project Manual are directly applicable to this Section, and this Section is directly applicable to them.
1.02 REFERENCE STANDARDS
A. The latest published edition of a reference shall be applicable to this Project unless identified by a specific edition date.
B. All reference amendments adopted prior to the effective date of this Contract shall be applicable to this Project.
C. All materials, installation and workmanship shall comply with all applicable requirements and standards.
1.03 QUALITY ASSURANCE
A. Special Requirements of Regulatory Agencies: Submit certification that system complies with VOC (Volatile Organic Compounds) requirements and regulations of the Environmental Protection Agency (EPA), Occupational Safety and Health Administration (OSHA), State, County, City, and local Air Control District.
[delete BELOW IF NO FIRERATED PLASTER WORK.]
[architect/engineer MUST DELETE EVERYTHING IN BLUE AND IN BRACKETS BEFORE PUBLISHING.]
B. Fire Resistance Ratings: Where plaster systems with fire resistance ratings are indicated, provide materials and installations identical to those of applicable assemblies tested per ASTM E 119 by fire testing laboratories acceptable to authorities having jurisdiction.
[delete BELOW IF NOT APPLICABLE TO ASSEMBLIES INDICATED. INDICATE RATING, TESTING AGENCY, AND TESTING AGENCY'S DESIGN DESIGNATION ON DRAWINGS.]
1. Fire-Resistance Ratings: As indicated by GA File Numbers in GA-600 "Fire Resistance Design Manual" or design designations in UL "Fire Resistance Directory" or in the listing of another testing and inspecting agency acceptable to authorities having jurisdiction.
[retain BELOW FOR BEST POSSIBLE CONSISTENCY IN THE WORK (OTHERWISE AUTHORIZATION TO SWITCH TO LIGHTWEIGHT AGGREGATES MIGHT BE ASSUMED WHEN SUCH WAS NOT INTENDED OR DESIRED).]
2. Provide plaster for fire resistance rated systems that has same aggregate as specified for similar nonrated Work, unless specified aggregate has not been tested by accepted fire testing laboratories.
[delete BELOW IF NO SUSPENDED PLASTER CEILINGS.]
C. Coordination of Work: Coordinate layout and installation of suspension system components for suspended ceilings with other work supported by or penetrating through ceiling.
[DELETE BELOW IF NOT REQUIRED. IF RETAINED, INDICATE LOCATION, SIZE, AND OTHER DETAILS OF MOCKUPS ON DRAWINGS OR BY INSERTS.]
D. Field Constructed Mock Up: Prior to installation of plaster work, fabricate panels for each type of finish and application required to verify selections made under sample submittals and to demonstrate aesthetic effects of application as well as qualities of materials and erection. Build mock ups to comply with the following requirements, using materials indicated for final unit of Work.
1. Locate mock ups on Site in location and size indicated or, if not indicated, directed by Architect.
[DELETE BELOW IF NOT REQUIRED.]
2. Erect 10 foot by 10 foot by full thickness mock up using materials, including lath and support system, indicated for final work.
3. Demonstrate the proposed range of aesthetic effects including color, texture, and workmanship to be expected in completed work.
4. Obtain Architect's acceptance of mock ups before start of plaster work.
5. Retain and maintain mock ups during construction in undisturbed condition as a standard for judging completed plaster work.
1.04 SUBMITTALS
A. Samples for Initial Selection: For each type of factory-prepared finish coat indicated.
[retain paragraph above if colors and other characteristics are not preselected and specified or scheduled.]
[Retain paragraph below with or without above.]
B. Samples for Verification Purposes:
1. Units at least twelve inches square of each type of finish indicated, in sets for each color, texture, and pattern specified, showing full range of variations expected in these characteristics.
2. 12 inch long sample of each metal trim accessory.
C. Product Data: Manufacturer’s technical literature for each product and system indicated, including installation instructions and recommendations for maintenance.
D. Shop Drawings: Show details of fabrication and installation, including plans, elevations, sections, details of components, and attachments to other work.
E. Record Documents: Provide record approved shop drawings and product data.
1.05 DELIVERY, STORAGE and HANDLING
A. Deliver materials in original packages, containers, or bundles bearing brand name and identification of manufacturer.
B. Store materials inside, under cover, and in manner to keep them dry, protected from weather, direct sunlight, surface contamination, aging, corrosion, and damage from construction traffic and other causes.
1.06 PROJECT CONDITIONS
A. Comply with requirements of referenced plaster application standards and recommendations of plaster manufacturer for environmental conditions before, during, and after application of plaster.
B. When ambient outdoor temperatures are below 40 degrees F (4.4 degrees C), maintain continuous uniform temperature of not less than 40 degrees F (4.4 degrees C) nor more than 80 degrees F (26 degrees C) for not less than 1 week prior to beginning plaster application, during its application, and until plaster is dry but for not less than one week after application is complete. Distribute heat evenly; prevent concentrated or uneven heat from contacting plaster near heat source.
C. Ventilate building spaces as required to remove water in excess of that required for hydration of plaster. Begin ventilation immediately after plaster is applied and continue until it sets.
D. Protect contiguous Work from soiling, spattering, moisture deterioration and other harmful effects that might result from plastering.
PART 2 - PRODUCTS
2.01 GENERAL
A. All materials shall meet or exceed all applicable referenced standards, federal, state and local requirements, and conform to codes and ordinances of authorities having jurisdiction.
2.02 METAL SUPPORTS FOR SUSPENDED AND FURRED CEILINGS
[DELETE THIS ARTICLE IF NO CEILINGS.]
A. Size metal ceiling supports to comply with the following, unless otherwise indicated.
1. Gypsum Plaster Installations: ASTM C 841.
[DELETE EITHER ABOVE OR BELOW IF INAPPLICABLE.]
2. Portland Cement Plaster Installation: ASTM C 1063.
[DELETE ANY COMPONENTS BELOW NOT REQUIRED.]
B. Wire for Hangers and Ties: ASTM A 641, Class 1 zinc coating, soft temper.
C. Rod Hangers: Mild steel, zinc or cadmium coated.
[KEEP ABOVE OR BELOW, OR BOTH, FOR USE IN SUPPORTING EXTERIOR SOFFITS. THE RIGID HANGERS PREVENT SOFFITS FROM "RISING" UNDER HIGH WIND LOADS.]
D. Flat Hangers: Mild steel, zinc or cadmium coated or protected with rust inhibitive paint.
E. Channels: Cold rolled steel, 0.05980 inch minimum thickness of base metal (uncoated), allowable bending stress of 18,000 psi, protected with rust inhibitive paint or galvanizing complying with ASTM A 653 for G60 coating designation, and as follows:
1. Carrying Channels: 1-1/2 inch deep by 7/16 inch wide flanges, 475 lbs. per 1000 feet painted, 508 lbs. per 1000 feet galvanized.
2. Furring Channels: 3/4 inch deep by 7/16 inch wide flanges, 300 lbs. per 1000 feet painted, 316 lbs. per 1000 feet galvanized.
[RETAIN BELOW WHERE CEILINGS ARE EXPOSED TO CORROSIVE ACTION OF SALT AIR, ETC. REVISE IF INTERIOR APPLICATIONS REQUIRE GALVANIZING.]
3. Provide galvanized channels for exterior, and high-humidity interior, installations.
[RETAIN BELOW UNLESS HANGERS CAN BE DIRECTLY TIED TO STRUCTURAL MEMBERS OR CONCRETE REINFORCEMENT. DIRECT ATTACHMENT OF HANGERS OR OTHER SUPPORTS TO METAL DECKING NOT ACCEPTABLE.]
F. Hanger Anchorage Devices: Screws, cast in place concrete inserts, or other devices appropriate for anchorage to the form of structural framing indicated and whose suitability for use intended has been proven through standard construction practices or certified test data.
[REVISE BELOW IF OTHER LOADING CRITERIA REQUIRED OR INSERT SPECIFIC DEVICES.]
1. Size devices to develop full strength of hanger but not less than 3 times calculated hanger loading, except size direct pullout concrete inserts for 5 times calculated hanger loading.
2.03 LATH
[RETAIN TYPES OF LATH REQUIRED. IF MORE THAN ONE TYPE, INDICATE LOCATION OF EACH ON DRAWINGS OR IN THIS SECTION BY INSERTS.]
A. Expanded Metal Lath: Fabricate expanded metal lath from steel sheet to produce lath complying with ASTM C 847, with ASTM A 653/A 653M, G60 (Z180) hot-dip galvanized zinc coating for type, configuration, and other characteristics indicated below.
1. Diamond Mesh Lath: Comply with the following requirements:
a. Configuration: Flat, Weight: 3.4 lbs. per sq. yd.
b. Configuration: Self furring, Weight: 3.4 lbs. per sq. yd.
[REVISE BELOW IF OTHER TYPE OF PAPER REQUIRED.]
c. Paper Backing: Where paper backed diamond mesh lath is indicated, provide asphalt impregnated paper factory bonded to back and complying with FS UU B 790, for Type I, Grade D (vapor permeable), Style 2.
2. Rib Lath: Comply with the following requirements:
a. Configuration: Rib depth of 3/8 inch, Weight: 3.4 lbs. per sq. yd.
[IF SHEET LATH, OR WIRE LATH REQUIRED, INSERT. REVISE BELOW IF SPECIFIC ATTACHMENT DEVICES REQUIRED.]
B. Lath Attachment Devices: Devices of material and type required by referenced standards and recommended by lath manufacturer for secure attachment of lath to framing members and of lath to lath.
2.04 PLASTER ACCESSORIES
A. Comply with material provisions of ASTM C 841 and ASTM C 1063; coordinate depth of accessories with thicknesses and number of coats required.
B. Metal Corner Reinforcement: Expanded large mesh diamond mesh lath fabricated from zinc alloy or welded wire mesh fabricated from 0.0475 inch diameter zinc coated (galvanized) wire and specially formed to reinforce external corners of portland cement plaster on exterior exposures while allowing full plaster encasement.
C. Fabricate metal beads and accessories from not less than 24 gage 99 percent pure zinc alloy to comply with ASTM B 69 at exterior and "high humidity" interior areas, and galvanized steel at other interior areas, except where extruded aluminum trim is shown. Coordinate depth of grounds with thickness and number of plaster coats required.
1. Square Edged Casing Beads: Manufacturer's standard with expanded or short flange to suit application.
2. Control Joints: Back-to-back J-shape with expanded flanges at flat plaster areas that permits positive locking with plaster.
3. Two Piece Expansion Joints: Roll-formed casing beads with modified back flanges providing positive slip joint action and dust barrier, adjustable for joint width variation of 1/8 inch to 5/8 inch.
4. Cornerite: Manufacturer's standard preformed interior corner reinforcement made from 2.5 lb./sq. yd. diamond mesh lath.
D. Aluminum Components: Alloy, temper, and finish recommended by manufacturer with not less than the strength and durability properties of aluminum extrusions complying with ASTM B 221 (ASTM B 221M) or alloy and temper 6063-T5.
[INSERT OTHER ACCESSORIES above AS REQUIRED.]
2.05 PORTLAND CEMENT PLASTER MATERIALS AND MIXES
A. Base Coat Materials:
1. Portland Cement: ASTM C 150, Type I.
2. Masonry Cement: ASTM C 91, Type N.
3. Lime: ASTM C 206, Type S special finishing hydrate.
4. Sand Aggregate: ASTM C 897.
[CONFIRM FIBER IS DESIRED FOR ADDITION TO MIX. THIS NORMALLY ISN'T USED BUT IT IS APPLICABLE IN CERTAIN APPLICATIONS.]
5. Fiber for Base Coat: Alkaline resistant glass fibers, 1/2" long, free of contaminants, manufactured for use in portland cement plaster.
B. Finish Coat Materials:
1. Factory Prepared Finish Coat: Manufacturer's standard product requiring addition of water only; white in color unless otherwise indicated.
[IF FACTORY-PREPARED FINISH COAT ABOVE IS RETAINED (WHICH IS TYPICAL), DELETE THE THREE MATERIALS BELOW.]
2. Portland Cement: ASTM C 150, Type I, white.
3. Lime: ASTM C 206, Type S special finishing hydrate.
4. Aggregate: ASTM C 897, manufactured or natural sand, white, or in color required to match Architect's accepted sample.
C. Portland Cement Plaster Mixes: Comply with ASTM C 926 for portland cement plaster base and finish coat mixes as applicable to plaster bases, materials, and other requirements indicated. Proportion materials for respective base coats in parts by volume for cementitious materials and in parts by volume per sum of cementitious materials for aggregates to comply with the following requirements for each method of application and plaster base indicated. Adjust mix proportions below within limits specified to attain workability.
[SELECT ONE OF THE FOLLOWING THREE MIXES AND DELETE THE REST. THE FIRST ONE IS THE MOST COMMON AND IS APPLICABLE FOR MOST APPLICATIONS. Decreasing the proportion of lime in the cementitious-material mix produces a harder surface but increases the possibility of cracking.]
[SECOND IS A VERY HIGH STRENGTH MIX.]
[THIRD IS A HIGH STRENGTH MIX.]
1. Scratch Coat: 1 part portland cement, 1 to 2 parts masonry cement, 2-1/2 to 4 parts sand.
2. Brown Coat: 1 part portland cement, 1 to 2 parts masonry cement, 3 to 5 parts sand.
3. Finish Coat: 1 part portland cement, 1-1/2 to 2 parts lime, 3 parts sand.
[IF FACTORY PREPARED FINISH COAT (STUCCO) IS DESIRED, DELETE THE FINISH COAT LISTING FROM THE SELECTED MIX AND RETAIN THE FOLLOWING INSTEAD. delete the following if finish coat is retained.]
4. Factory Prepared Portland Cement Finish Coat: Add water only; comply with finish coat manufacturer's directions.
5. Scratch Coat: 1 part portland cement, 0 to 3/4 parts lime, 2-1/2 to 4 parts sand.
6. Brown Coat: 1 part portland cement, 0 to 3/4 parts lime, 3 to 5 parts sand.
7. Finish Coat: 1 part portland cement, 3/4 to 1-1/2 parts lime, 3 parts sand.
8. Scratch Coat: 1 part portland cement, 3/4 to 1-1/2 parts lime, 2-1/2 to 4 parts sand.
9. Brown Coat: 1 part portland cement, 3/4 to 1-1/2 parts lime, 3 to 5 parts sand.
10. Finish Coat: 1 part portland cement, 1 part masonry cement, 3 parts sand.
[ADD THE FIBER PARAGRAPH BELOW TO THE SELECTED MIX ABOVE IF DESIRED.]
11. Fiber Content: Add fiber to scratch and brown coats above to comply with fiber manufacturer's directions but not to exceed 2 lb./cu. ft. of cementitious materials. Reduce aggregate quantities accordingly to maintain workability.
2.06 GYPSUM PLASTER MATERIALS AND MIXES
A. Base Coat Plaster Materials:
[BELOW IS TYPICAL BROWN COAT MATERIAL.]
1. Gypsum neat plaster complying with ASTM C 28. Subject to compliance with requirements, provide one of the following:
a. Red Top Gypsum Plaster; United States Gypsum Co.
b. Red Top Two Purpose Plaster; United States Gypsum Co.
c. Two Way Hardwall Plaster; Gold Bond Building Products Division, National Gypsum Co.