SECTION 09 21 16 GYPSUM BOARD ASSEMBLIES PART 1 GENERAL 1.1 SECTION INCLUDES A. Metal stud wall and ceiling framing, 20 gauge. B. Metal channel suspended ceiling framing. C. Gypsum board. D. Gypsum sheathing. E. Taped and sanded joint treatment. F. Edge trim, reveals and moldings. G. Fire rated shaft wall systems with ratings as listed on the drawings. 1.2 RELATED SECTIONS A. Section 05 40 00 - Cold Formed Metal Framing. B. Section 07 21 13 - Board Insulation. 1.3 REFERENCES A. ANSI/ASTM C36 - Gypsum Wallboard. B. ANSI/ASTM C79 - Gypsum Sheathing Board. C. ASTM C423 Sound Absorption and Sound Absorption Coefficients by the Reverberation Room Method. D. ANSI/ASTM C475 - Joint Treatment Materials for Gypsum Wallboard Construction. E. ANSI/ASTM C630 - Water Resistant Gypsum Backing Board. F. ANSI/ASTM C645 - Non-Load (Axial) Bearing Steel Studs, Runners (Track), and Rigid Furring Channels for Screw Application of Gypsum Board. G. ASTM E795 Standard Practices for Mounting Test Specimens During Sound Absorption Tests. H. USG's Gypsum Construction Handbook. I. IBC, 2012 Edition. 1.4 SUBMITTALS Standard Specifications 09 21 16 Page 1 of 6
A. Product Data: Include manufacturer's literature on metal framing, ceiling suspension systems, gypsum board, joint tape and compound. Include test data verifying acoustical performance. 1.5 REGULATORY REQUIREMENTS A. Conform to the requirements of IBC except where more restrictive requirements are specified in this section. PART 2 PRODUCTS 2.1 ACCEPTABLE MANUFACTURERS - GYPSUM BOARD SYSTEM A. United States Gypsum Co. B. Celotex. C. Georgia Pacific. D. Pabco. E. James Hardie Gypsum 2.2 FRAMING MATERIALS A. Studs and Tracks: ANSI/ASTM C645; galvanized, sizes and shapes shown on the drawings. Provide 20 gauge C studs unless noted otherwise. Framing shown as 18 gauge or heavier is specified under Section 05 40 00 - Cold Formed Metal Framing. B. Backing: Galvanized sheet metal, 20 gauge. C. Resilient Channels: 25 ga. hat shaped formed steel. D. Furring Channels: 20 ga., 7/8" hat shaped formed steel. E. Ceiling Channels: 16 ga., 1-1/2" cold rolled galvanized steel. F. Hanger Wire: 8 ga. galvanized steel. G. Ceiling Struts: Pre-manufactured struts, specifically designed for horizontal restraint of suspended ceiling systems, similar to USG'S Donn Compression Posts. H. Galvanized "Z" channels for board insulation attachment are specified in Section 07 21 13 Board Insulation. I. Ceiling Edge Reveal: 20 gage sheet metal in size and configuration as shown on drawings. J. Shaft Wall Systems: Materials and methods in accordance with agency rating requirements. 2.3 GYPSUM BOARD MATERIALS A. Gypsum Board: ANSI/ASTM C36; fire resistive type X, UL rated; 5/8 inch, maximum permissible length; ends square cut, tapered edges. Standard Specifications 09 21 16 Page 2 of 6
B. Moisture Resistant Gypsum Board: ANSI/ASTM C630; 5/8 inch, maximum permissible length; ends square cut, tapered edges. C. Gypsum Sheathing Board: ASTM C79, moisture resistant type, 1/2 inch thick, maximum permissible lengths, square cut ends and edges, water repellent paper faces. D. Gypsum Liner Panels: ANSI/ASTM C36, fire resistive type X, UL rated; 1 inch thick. E. Cement board: ½ inch thick. 2.4 ACCESSORIES A. Acoustical Sealant: Non-hardening, permanently resilient and non-skinning, for use in conjunction with gypsum board. B. Corner Beads: Metal. (No paper) C. Joint Materials: ANSI/ASTM C475; reinforcing tape, joint compound, adhesive, water, and fasteners. D. Control Joint: USG 093. E. Texture Material: Spray-applied, compatible with joint system. Provide "Orange Peel" texture unless noted otherwise. Texture to match existing finish. F. Fasteners: Type S self tapping screws in size and spacing as required by IBC or rating of gypsum board wall system. G. Duct Liner: Manufacturer's standard 2 inch thick black faced duct liner; 1.5 pcf to 3 pcf. Acoustical performance: Minimum NRC 0.95 (ASTM C423) when tested with Type A mount (ASTM E795). H. Outlet Acoustical Box Pad: Self adhesive polybutenebutyl pads by Harry A. Lowry & Associates, or equal. PART 3 EXECUTION 3.1 INSPECTION A. Verify that site conditions are ready to receive work. B. Coordinate with installer of ceramic tile for installation of backing board in lieu of gypsum board as specified in Section 09 30 13 Ceramic Tile. C Beginning of installation means acceptance of substrate. 3.2 METAL STUD INSTALLATION A. Accurately layout partition and wall lines from the dimensions shown on the Drawings. B. Install metal studs and accessories in accordance with the manufacturer's recommendations and recommended industry practices included in USG's Gypsum Standard Specifications 09 21 16 Page 3 of 6
Construction Handbook, anchoring all components firmly into position. Minimum 20 gauge 3 5/8 inch studs for wall construction. C. Align partition and wall assemblies to a tolerance of one in 200 horizontally and one in 500 vertically. D. Space studs as required for compliance with pertinent regulations and as noted on drawings. Space studs at 16" O.C. and 24 O.C. for C-H studs. E. Provide minimum three studs at all corners and provide double studs at all wall openings, door and window jambs. F. Provide sheet metal backing/blocking for support of all wall mounted equipment and fixtures including, but not limited to, plumbing fixtures, toilet partitions, wall cabinets, toilet accessories, hardware, handrails, grab bars, mirrors, marker and tack boards, draperies, base boards, monitors and other wall mounted items. G. Coordinate with other trades for proper size, spacing, thickness and attachment requirements of backing/blocking. Provide 20 gauge sheet metal unless otherwise shown on the drawings or required by a specific item. H. Coordinate requirements for pipes, ducts, conduits and other items required to be enclosed within the partition and wall system. I. Shaft wall systems shall be installed in strict accordance with the requirements of the rating agency. J. Provide double studs, back to back, for location of expansion joints in gypsum board. 3.3 CEILING INSTALLATION A. Install system capable of supporting imposed loads to a deflection of 1/360 maximum. B. Install after major above ceiling work is complete. Coordinate the location of hangers with other work. C. Hang suspension system independent of walls, columns, ducts, pipes and conduit. Where carrying members are spliced, avoid visible displacement of face plane of adjacent members. D. Where ducts or other equipment prevent the regular spacing of hangers, reinforce the nearest affected hangers and related carrying channels to span the extra distance. E. Space hanger wires as required by IBC for carrying channel spacing and within 6" of ends. F. Install carrying channels at 36" O.C. and within 6" of walls. Provide 1" clearance between channels and abutting walls. G. Lap channels 12" at splices. H. Install furring channels at right angles to carrying channels at 16" O.C. and within 6" of walls and maintain 1" clearance to walls. I. Secure channels and splices with 18 ga. tie wire. Standard Specifications 09 21 16 Page 4 of 6
J. Reinforce openings in ceiling which interrupt carrying or furring channels with lateral channel bracing. K. Install perimeter edge reveal sheet metal per manufacturer s recommendations. L. Provide horizontal restraint consisting of: 1. Four No. 12 gauge wires secured to main runners within 2 inches of cross runner intersection and splayed 90 degrees from each other at an angle not exceeding 45 degrees from the plane of the ceiling. 2. Struts fastened to the main runner extending to and fastening to structure above. Place struts 12 feet on center in both directions with the first point within 6 feet from each wall. M. Shaft wall ceiling systems shall be installed in strict accordance with the requirements of the rating agency. N. Install to meet IBC Seismic Requirements and Clark County amended codes. O. When ceiling is open on edges or you can visually see above the ceiling, the area visable is to be painted black (blacked out). 3.4 ACOUSTICAL ACCESSORIES INSTALLATION A. Install resilient channels at maximum 24 inches on center. Locate joints over framing members. B. Install acoustical sealant within partitions in accordance with manufacturer's instructions. C. Install duct liner board with manufacturer's recommended adhesive and mechanical fasteners where appropriate. Boards to be placed tight to each other and to perimeter. Touch-up any damaged or abraded areas with flat black paint to provide a solid black surface. D. Outlet Acoustical Box Pads: Wrap around sides and back of electrical boxes. Leave no gaps. 3.5 GYPSUM BOARD INSTALLATION A. Install gypsum board in accordance with manufacturer's instructions, recommended industry practices included in USG's Gypsum Construction Handbook and in accordance with requirements of assembly rating where rated construction is called for. B. Erect single layer board in either horizontal or vertical direction, with ends and edges occurring over firm bearing except where treated joints occur at right angles to framing or furring. C. Use screws when fastening gypsum board to metal furring or framing. D. Double Layer Applications: Use gypsum backing board for first layer, placed perpendicular to framing or furring members. Place second layer perpendicular to first layer. Offset joints of second layer from joints of first layer. E. Double Layer Applications: Secure second layer to first in manufacturer's instructions. Standard Specifications 09 21 16 Page 5 of 6
F. Treat cut edges and holes in moisture resistant gypsum board and exterior gypsum ceiling board with sealant. G. Place control joints consistent with lines of building spaces, and at a maximum of 30 feet center to center. Also place control joints where base wall construction contains building control or expansion joints. Where joint is in rated wall add additional layer of board to maintain fire rating. H. Place corner beads at external corners. Use longest practical length. Place edge trim gypsum board abuts dissimilar materials as indicated I. Erect exterior gypsum sheathing horizontally, with edges butted tight and ends occurring over firm bearing. J. Install reveals and trim in accordance with details on drawings. 3.6 JOINT TREATMENT A. Provide tape and joint compound finish at all exposed joints edges and corners to smooth surface ready to receive finishes. B. Apply tape pressed into joint compound or by mechanical tool designed for this process. C. Apply second coat of joint compound to extend beyond joint center approximately 3-1/2 inches. Apply to a smooth even plane. After drying or setting sand or smooth as needed to eliminate high spots or excessive compound. D. Apply third coat of joint compound except at concealed locations not subject to view. Third coat shall be applied to feather edges approximately 6 inches from center of joint. After drying, lightly sand to leave a smooth even surface. E. Provide spray-applied texture at all gypsum board exposed to view. Provide sample panel of texture for approval of Owner prior to start of texture application. 3.7 TOLERANCES A. Maximum Variation from True Flatness: 1/8 inch in 10 feet in any direction. END OF SECTION Standard Specifications 09 21 16 Page 6 of 6