SECTION GYPSUM BOARD SYSTEM

Transcription

1 SECTION GYPSUM BOARD SYSTEM PART 1 GENERAL 1.1 RELATED DOCUMENTS A. The provisions of the General Conditions, Supplementary Conditions, and the Sections included under Division 1, General Requirements, are included as a part of this Section as though bound herein. 1.2 SECTION INCLUDES A. Gypsum Board Partition Systems B. Gypsum Board Accessories C. Joint Treatment D. Textured Finish 1.3 REFERENCES A. ASTM C36/C36M Standard Specification for Gypsum Wallboard B. ASTM C79/C79M Standard Specification for Treated Core and Non-treated Core Gypsum Sheathing Board C. ASTM C442/C442M Standard Specification for Gypsum Backing Board and Coreboard, and Gypsum Shaftliner Board D. ASTM C475 Standard Specification for Joint Compound and Joint Tape for Finishing Gypsum Board E. ASTM C630/C630M Standard Specification for Water Resistant Gypsum Backing Board F. ASTM C645 Standard Specification for Nonstructural Steel Framing Members G. ASTM C754 Standard Specification for Installation of Steel Framing Members to Receive Screw Attached Gypsum Panel Products H. ASTM C931/C931M - Standard Specification for Exterior Gypsum Soffit Board I. ASTM E695 Standard method for Measuring Relative Resistance of Wall, Floor, and Roof Construction to Impact loading J. ASTM D3273 Standard Test Method for Resistance to Growth of Mold on the Surface of Interior Coatings in an Environmental Chamber K. ASTM D5420 Standard Test Method for Impact Resistance of Flat Rigid Plastic Specimen By Means of a Striker Impacted by Falling Weight (Gardner Impact) L. ASTM E119 Standard Test Methods for Fire Tests of Building Construction and Materials M. ASTM C840 Standard Specification for the Application and Finishing of Gypsum Board N. GA 201 Using Gypsum Board for Walls and Ceilings O. GA-216 Recommended Specifications for the Application and Finishing of Gypsum Board P. GA-600 Fire Resistance Design Manual Q. Florida Building Code (FBC) 1.4 SUBMITTALS A. Product Data: Submit manufacturer's product data sheets and printed installation instructions for each product or system proposed for use. Architect s Project Number of 7 Gypsum Board System

2 1.5 QUALITY ASSURANCE A. Perform gypsum board systems work in accordance with recommendations of ASTM C754, C840, and GA-216 except as otherwise specified in this Section. B. Regulatory Requirements: 1. Fire-rated Assemblies: Listed and rated by Underwriter's Laboratories, Inc. or generic fire resistance ratings listed in GA Fire-Hazard Classification: Listed and labeled by Underwriter's Laboratories, Inc. 1.6 COORDINATION A. Prior to and during installation, coordinate with work of other trades to facilities required openings and finishes. B. Conduct pre-construction meeting with drywall contractor, architect, owner, project coordinator, and others involved with process. 1.7 DELIVERY, STORAGE AND HANDLING A. Store the material off the floor in dry area to prevent damage from moisture or excessive handling. B. Follow manufacturer's requirements for on site storage and handling of materials. 1.8 PROJECT CONDITIONS A. Environmental Conditions, General: Establish and maintain environmental conditions for applying and finishing gypsum board to comply with ASTM C840 and with gypsum board manufacturer's recommendations. B. Room Temperatures: For non-adhesive attachment of gypsum board to framing, maintain not less than 40 degrees F. For adhesive attachment and finishing of gypsum board, maintain not less than 50 degrees F. for 48 hours prior to application and continuously after until dry. Do not exceed 95 degrees F. when using temporary heat sources. C. Ventilation: Ventilate building spaces, as required, for dry joint treatment materials. Avoid drafts during hot dry weather to prevent finishing materials from drying too rapidly. PART 2 PRODUCTS 2.1 MANUFACTURERS A. U.S. Gypsum Co products listed as a standard of quality. B. Use products manufactured by United States based companies only, do not use drywall manufactured in China. 1. National Gypsum Corp 2. U.S. Gypsum Corp 3. Georgia-Pacific Corp 4. Lafarge North America Inc 5. Other approved equal C. All gypsum board products shall have minimum mold growth ASTM D3273 rating of MATERIALS Architect s Project Number of 7 Gypsum Board System

3 A. Furring Channels: USG metal stud channel, 1½" deep, roll-formed sections of 20-ga galvanized steel, ASTM C645 B. Gypsum Wallboard (General and above 8' AFF): ⅝" thick, ASTM C36/C36M, tapered edge, fire rated Type X. (Note: At radius walls the Contractor has the option to install ¼" and/or ⅜" thick gypsum wallboard in layers.) C. Gypsum Wallboard (Corridors, stairways, cafeteria, stage, and gymnasium up to at least 8' AFF minimum): Abuse resistant brand, ⅝" thick, ASTM C36/C36M, tapered edge, fire rated Type X. (Note: At radius walls the Contractor has the option to install ¼" and/or ⅜" thick gypsum wallboard in layers.) 1. Acceptable abuse resistant drywall: a. Fiber Rock VHI by USG b. Or approved equal D. Water Resistant Gypsum Wallboard: ⅝" thick, tapered edge 1. Provide at wet areas (areas subject to contact with water), as shown on plans. E. Cementitious backer board for tile and wet locations: Complying with ANSI A118.9 of thickness indicated and in maximum lengths available to minimize end-to-end butt joints. Ends and edges shall be square cut and finished smooth; formed in a continuous process of aggregated Portland cement slurry; and reinforced with vinyl coated, woven glass-fiber mesh embedded in both surfaces. 1. Thickness: Manufacturer s standard thickness, but not less than 7/16 inch, unless otherwise indicated. 2. Products: Subject to compliance with requirements, provide one of the following products: a. Wonderboard Multi-Board; Custom Building Products. b. DonCrete Cementitious Tile Backer Board; Domtar Gypsum. c. Durock Cement Board; United States Gypsum Co. F. Exterior Gypsum Soffit Board: 5/8" "DensGlass Gold Fireguard" complying with ASTM C1177. G. Gypsum Backing Board: Standard or Fire Rated type, square edges, ASTM C442/C442M. H. Gypsum Sheathing 5/8" thick exterior water resistant board for metal framing systems with book tongue and grooved edges. 1. Acceptable product shall be DensGlass Gold Exterior Guard, or similar product by other approved manufacturers in 2.1 of this section. I. Sound Board: Acoustically enhanced gypsum board shall be 5/8" thick, Type "X" sound break as manufactured by National Gypsum Co. or approved equal. Gypsum board shall be moisture resistant and comply with ASTM D 3273, score of 10 and comply with ASTM G21, score of MISCELLANEOUS MATERIALS A. Joint treatment materials and adhesives shall be as recommended by the gypsum board manufacturer. Joint tape shall be paper-reinforcing tape, unless otherwise recommended by gypsum board manufacturer for use with setting type compound. 1. Setting Type Joint Compounds for Gypsum Board: Factory packaged, job mixed, and chemical hardening powder products formulated for use indicated. a. Where setting type joint compounds are indicated as a taping compound only or for taping and filling only, use formulation that is compatible with other joint compounds applied over it. b. For prefilling gypsum board joints, use formulation recommended by gypsum board manufacturer. Architect s Project Number of 7 Gypsum Board System

4 c. For filling joints and treating fasteners of water resistant gypsum backing board behind base for ceramic tile, use formulation recommended by gypsum board manufacturer. d. Drying Type Joint Compounds for Gypsum Board: Factory packaged vinyl based products complying with the following requirements for formulation and intended use. e. Ready Mixed Formulation: Factory mixed product 1) Topping compound formulated for finish (third) coats. 2) All-purpose compound formulated for topping compound. B. Joint Compound for Cementitious Backer Board: Material recommended by cementitious backer unit manufacturer. C. Joint compound for gypsum sheathing board. G.P. setting type joint compound. D. Joint Tape for Cementitious Backer Board: Polymer-Coated, open glass-fiber mesh recommended by cementitious backer unit manufacturer. E. Screws for Gypsum Board (ASTM C1002): Phillips head galvanized steel Type "S" or "S-12" self-drilling screws, length and type as required and recommended by gypsum board manufacturer. F. Screws for Gypsum Sheathing Board. 1. Type S-12, Bugle head, self-tapping, rust-resistant, fine tread for heavy gauge steel. 2. Type S, bugle head, rust resistant, sharp point, and fine thread for light gauge steel or furring. G. Accessories for Interior Installation: Corner bead, edge trim, and control joints complying with ASTM C1047 and requirements indicated below: 1. Material: Formed metal with metal complying with the following requirements: a. Steel sheet zinc coated by hot-dip or electrolytic process, or steel sheet coated with aluminum or rolled zinc. b. Do not use plastic accessories. 2. Shapes indicated below by reference Figure 1 designations in ASTM C1047: a. Corner bead on outside corners, unless otherwise indicated. 1) Product shall be similar to Dur-A-Bead Corner Bead (103) ; USG or as approved by board manufacturer and Architect. b. L-bead with face flange only; face flanged formed to receive joint compound. Use L-beads for edge trim (perimeter relief). 1) Product shall be similar to No. 200-B Metal Trim ; USG or as approved by board manufacturer and Architect. c. One-piece control joint formed with V-shaped slot and removable strip covering slot opening. 1) Product shall be similar to No. 093 Control Joint ; USG or as approved by board manufacturer and Architect. H. Sheathing Tape: 2-1/2 inch wide, 10 by 10 self-adhering fiberglass reinforced joint tape like No Contractor Sheathing Tape as produced by the 3M Company of St. Paul, Minnesota. I. Spot Grout: ASTM C475, setting type joint compound recommended for spot grouting hollow metal doorframes. J. Asphalt Saturated Organic Felt: ASTM D 226, Type I (No. 15 asphalt felt), nonperforated. K. Foam Gaskets: Closed cell vinyl foam adhesive backed strips that allow fastener penetration without foam displacement, 1/8 inch thick, in width to suit metal stud size indicated. L. Gypsum board sheathing sealants, caulk, tape: 1. Don Corning 795 or equivalent; Pecora 895 or equivalent 2. Borden HPPG Elmer s siliconized acrylic latex caulk or equivalent wide 10 x 10 glass mesh quick tape or equivalent. Architect s Project Number of 7 Gypsum Board System

5 2.4 ACOUSTICAL INSULATION MATERIALS A. Sound-Attenuation Blankets: Unfaced mineral-fiber blanket insulation produced by combining mineral fibers of type described below with thermosetting resins to comply with ASTM C 665 for Type I (blankets without facing membrane), unless noted otherwise. 1. Mineral-Fiber Type: Fibers manufactured from glass, slag wool, or rock wool. a. Where used in fire-resistance rated assemblies, mineral fiber types shall correspond with requirements of tested assemblies. B. Acoustical Insulation Blankets: Semi rigid, spun, mineral fiber, similar to "Thermafiber" as manufactured by United States Gypsum. Blankets shall be 2 inches thick minimum with 2.5 PCF density minimum. Width of blanket shall match spacing of studs and length of blanket shall be 48 inches. 1. Application: Provide where "Sound-Attenuation Blankets" do not meet the requirements of the fire-resistance rated assemblies indicated. C. Acoustical Sealant for Exposed and Concealed Joints: Manufacturer s standard nonsag, paintable, nonstaining latex sealant complying with ASTM C 834 and the following requirements: 1. Product is effective in reducing airborne sound transmission through perimeter joints and openings in building construction as demonstrated by testing representative assemblies according to ASTM E Products: Subject to compliance with requirements, provide one of the following: a. PL Acoustical Sealant; ChemRex, Inc.; Contech Brands. b. AC-20 FTR Acoustical and Insulation Sealant; Pecora Corp. c. Sheetrock Acoustical Sealant; United States Gypsum Co. D. Acoustical Sealant for Concealed Joints: Manufacturer s standard nondrying, nonhardening, nonskinning, nonstaining, gunnable, synthetic rubber sealant recommended for sealing interior concealed joints to reduce transmission of airborne sound. 1. Products: Subject to compliance with requirements, provide one of the following: a. BA-98; Pecora Corp. b. Tremco Acoustical Sealant; Tremco, Inc. PART 3 EXECUTION 3.1 EXAMINATION A. Examine adjacent construction for conditions that prevent proper installation of drywall systems. B. Do not proceed until defects are corrected. 3.2 GYPSUM BOARD APPLICATION METHODS A. Gypsum Board Application and Finishing Standards: Install and finish gypsum panels to comply with ASTM C840 and GA-216. B. Work shall be provided in accordance with the manufacturer's printed instructions and as specified herein. Where fire rating requirements for systems are indicated on the Drawings or in the schedules, install components in accordance with manufacturer's instructions to comply with indicated fire rating requirements. C. Wallboard joints shall be butted tightly together. Maximum allowable gap at end joints shall be 1/8 inch. Support end joints on framing members. Architect s Project Number of 7 Gypsum Board System

6 1. On partitions/walls apply gypsum panels vertically, unless parallel application is required for fire-resistive-rated assemblies. Use maximum length panels to minimize end joints. 2. Install ceiling boards in direction, either parallel or perpendicular to framing members, which results in the least number of joints. Install in maximum practical lengths to span with minimum number of end (butt) joints. Stagger end joints of adjoining boards. 3. Where ceiling or walls consist of 2 layers, face layer shall be installed perpendicular to base layer. Base layer to be screw attached and face layer to be strip laminated per manufacturer's instructions and screw attached to base layer in accordance with gypsum board application and finishing standards. Lay out joints so that tapered edges do not align with edges of openings. 4. Fire Rated Walls: Construct required rated wall using thickness of Type "X" gypsum board required by code, installed to code requirements. 5. Do not attach wallboard to head track. 6. Provide a minimum of 1/4 inch perimeter relief where board abuts different materials. Trim edges with U-bead edge trim, where edges of gypsum panels are exposed. Seal joints between edges and abutting structural surfaces with acoustical sealant. 7. Provide no less than ¼, nor more than 3/8, space at bottom of board above floor. D. Wall Tile Substrates: For substrates indicated to receive thin-set ceramic tile and similar rigid applied wall finishes, comply with the following: 1. Install cementitious backer units where tile is to be installed to comply with ANSI A Refer to Tile Specification. E. Soffits and Ceilings: Apply exterior gypsum soffit board panels perpendicular to supports, with end joints staggered over supports. Install with 1/4 inch open space where panels abut other construction or structural penetrations. 1. Fasten with corrosion-resistant screws. F. Openings cut in gypsum board to fit electrical outlets, plumbing, and piping shall fit snugly and shall be small enough to be covered by plates and escutcheons. Both face and back paper shall be cut for cutouts that are not made by use of a saw. G. Fasteners: Install fasteners no closer than 3/8 inch to end or edge. Space fasteners approximately 7 inches o.c., opposite each other on adjacent ends or edges. Begin fastening from center of wallboard and proceed toward outer end or edges. H. Apply pressure on gypsum board, adjacent to fasteners being driven, to insure that gypsum board will be secured tightly to framing member. Check for looseness at fasteners. Drive fastener with shank reasonably perpendicular to face of board. I. Drive screws with power screwdriver as recommended by gypsum board manufacturer. Surface of head shall be below surface of paper without cutting paper. J. Joint and corner treatment shall be in accordance with the manufacturer's printed instructions to provide a finished surface, ready for painting. Surface shall be free of dimples, excess finishing compound, ridges, or untrue corners. 1. Install edge trim where edge of gypsum panels would otherwise be exposed or semiexposed. Provide edge trim type with face flange formed to receive joint compound except where other types are indicated. K. Provide control joints in gypsum board partitions, bulkheads, ceilings, and soffits as follows: 1. Partition, furring, or column fireproofing abuts a structural element (except floor) or dissimilar wall or ceiling. 2. Ceiling or soffit abuts a structural element, dissimilar wall or partition or other vertical penetration. 3. Construction changes within plane of partition or ceiling. 4. Partition or furring run exceeds 40 feet, unless noted otherwise. 5. Ceiling dimensions exceed 50 feet in either direction. Architect s Project Number of 7 Gypsum Board System

7 6. Exterior soffits exceed 30 feet in either direction. 7. Wings of L, U, and T -shaped ceiling areas are joined. 8. Expansion or control joints occur in the exterior wall. 9. Less than ceiling height frames should have control joints extending to the ceiling from both corners. Ceiling height door frames may be used as control joints. Treat window openings in same manner as doors. 10. USG Control Joint No. 093: Apply over face of gypsum board where specified. Cut to length with a fine-toothed hacksaw (32 teeth per inch). Cut end joints square, butt together, and align to provide neat fit. Attach control joint to gypsum board with fasteners spaced 6 inches o.c. maximum along each flange. Remove plastic tape after finishing with joint compound or veneer finish. a. Leave a 1/2 inch continuous opening between gypsum boards for insertion of surfacemounted joint. b. Interrupt wood floor and ceiling plates with a 1/2 inch gap, wherever there is a control joint in the structure. c. Do not attach gypsum board to steel studs on one side of control joint. d. Provide separate supports for each control joint flange. e. Provide an adequate seal behind control joint where sound or fire ratings are prime considerations. L. Spot grout hollow metal door frames. Apply grout at each jamb anchor clip and immediately insert gypsum panels into frames. M. Direct Bonding to Substrate: Where gypsum panels are indicated as directly adhered to a substrate, comply with gypsum board manufacturer s recommendations, and temporarily brace of fasten gypsum panels until fastening adhesive has set. 3.3 ACCESSORIES INSTALLATION A. Corner Beads: Install on external corners, with screws spaced 8" o.c. both sides. B. Trim: Install over face-layer gypsum board with fasteners spaced 8" o.c. Install where gypsum board surfaces meet dissimilar surfaces and at other detailed locations. C. Corner beads and trim may be either galvanized metal or plastic. 3.4 JOINT TREATMENT A. Treat joints, interior angles, fastener depressions, and finishing trim on face-layer gypsum board, including gypsum board in ceiling plenums. B. Pre-fill, tape, fill, and finish in accordance with manufacturer's directions. C. Apply a thin skim coat of joint compound over entire surface of gypsum board. D. Sand finish coat and leave surfaces smooth, uniform, and free of fins, depressions, cracks and other imperfections. 3.5 SITE ENVIRONMENTAL PROCEDURES A. Indoor Air Quality: 1. Temporary ventilation: Provide temporary ventilation for work of this Section. 2. Multi-layer gypsum board: Screw attachment. Adhesive attachment will not be permitted. END OF SECTION Architect s Project Number of 7 Gypsum Board System