SECTION GYPSUM BOARD ASSEMBLIES

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1 1 PART ONE - GENERAL 1.1 COORDINATION SECTION GYPSUM BOARD ASSEMBLIES A. Drawings and General provisions of the Contract including General and Supplementary Conditions and Division 1 Specification Sections apply to this Section. 1.2 SUMMARY A. Work of this Section shall include, but not necessarily be limited to, the following: 1. Interior gypsum drywall partitions and furring. 2. Interior suspended gypsum board ceilings. 3. Exterior gypsum sheathing. 4. Flat Straps for wall mount items such as Marker Board/Tack Board. 1.3 RELATED SECTIONS A. Section Carpentry (wood blocking) B. Section Cold formed steel framing C. Section Dampproofing and flashing D. Section Insulation E. Section Firestopping F. Section Ceramic tile G. Section Painting H. Section Vinyl wall covering I. Mechanical systems - Specification Division 15 Sections J. Electrical systems - Specification Division 16 Sections. 1.4 DELIVERY AND STORAGE OF MATERIALS A. All materials shall be delivered in their original unopened packages and stored in an enclosed shelter providing protection from damage and exposure to the

2 elements. Damaged or deteriorated materials shall be removed from the premises. 1.5 ENVIRONMENTAL CONDITIONS A. During cold weather installation of gypsum panels and joint finishing, temperatures within the building shall be maintained within the range of 55 to 75 degrees F. Adequate ventilation shall be provided to carry off excess moisture. 1.6 SUBMITTALS A. Reference Section Submittal Procedures. B. Product Data: Submit manufacturers' product specifications and installation instructions for each gypsum system drywall component, and other data as may be required to show compliance with these specifications. 1.7 QUALITY ASSURANCE A. Fire-Test-Response Characteristics: Where fire-rated gypsum board assemblies are indicated, provide materials and construction identical to those of assemblies tested for fire resistance per ASTM E 119 by an independent testing and inspecting agency acceptable to authorities having jurisdiction. 1. Fire Resistance Ratings: As indicated by reference to Gypsum Association GA File Numbers in GA-600 Fire Resistance Design Manual or to design designations in UL Fire Resistance Directory or in the listing of another testing and inspecting agency acceptable to authorities having jurisdiction. B. Single-Source Responsibility for Steel Framing: Obtain steel framing members for gypsum board assemblies from a single manufacturer. C. Single-Source Responsibility for Panel Products: Obtain each type of gypsum board and other panel products from a single manufacturer. D. Perform Work in accordance with Gypsum Association Publication Manuals: 1. GA-201 Using Gypsum Board for Walls and Ceilings 2. GA-216 Application and Finishing of Gypsum Board 3. GA-600 Fire Resistance Design Manual. 4. GA-214 Recommended Levels of Gypsum Board Finish. 2 PART TWO - PRODUCTS 2.1 MANUFACTURERS A. Steel Stud Wall and Partition Framing: Unimast Inc., Dietrich Metals, Dale Industries, Delta Metals, Harrison Metals, Alabama Metal Industries, Corp., Clark Steel Framing Systems, Superior Steel Studs, Inc., Texas Lightsteel Products, Inc

3 B. Gypsum Board and Related Accessories: United States Gypsum Co., National Gypsum Co., Domtar Gypsum, Inc., Georgia Pacific, Temple Inland, G-P Gypsum Corp. C. Drywall Trim, Moldings and Accessories: 1. Any listed gypsum board manufacturers. 2. Dale Industries Incorporated 3. Fry Reglet 4. MM Systems Corporation D. Acoustical Sealant: Tremco, Polymeric Systems PSI-901, Pecora, United Gypsum Company. 2.2 MATERIALS A. Steel Drywall Framing: 1. Studs and Runners: Screw-type complying with ASTM C645. Provide studs of the size indicated with runners of compatible size for friction fit to studs. Fabricate from a minimum of 20 gauge steel unless heavier gauge is indicated with manufacturer's standard zinc protective coating. 2. Rigid Furring Channels: Screw type furring channels complying with ASTM C645, fabricated from 25 gauge steel with manufacturer's standard zinc protective coating. 3. Flat strap for wall mount items support to be L6 gage 8" high continuous. 4. Cold-rolled channels, 3/4 inch and 1-1/2 inch. 5. Hanger wire: 8 gage, galvanized. 6. Tie wire: 16 gage, galvanized. 7. Back up steel plate for maker board: 16" gage, 6" wide continuous steel plate. B. Gypsum Drywall Board 1. Face boards, ASTM C1396, Type-X, 5/8 inch thick, unless otherwise noted in the drawings, 48 inch wide panels, lengths as required, long edges tapered to receive manufacturer's standard joint treatment. 2. Water-resistant applications: Substrate for non-absorbent ceramic tile to have core and paper facings treated to resist moisture per ASTM C630 and Type-X requirements. C. Screw Fasteners 1. Type S Bugle Head screws complying to ASTM C1002 to attach gypsum panels to steel framing with a thickness less than 20 gauge. 2. Type S-12 Bugle Head screws complying to ASTM C954 to attach gypsum panels to steel framing with a thickness of 20 gauge or greater. 3. Bugle Head ITW Buildex self tapping screws with Climaseal finish, at exterior walls

4 D. Drywall Accessories: 1. Drywall Sealant: Provide non-drying, non-shrinking, non-migrating sealant recommended by the drywall manufacturer. Provide sealant which is paintable wherever exposed to view. 2. Metal Trim Accessories: Provide trim accessories of the sizes required for the drywall applications shown and specified, fabricated from galvanized steel, and of the following types: a. At external corners, provide corner bead with smooth, rigid metal nose bonded to paper tape flanges. b. Where drywall abuts or intersects dissimilar construction, provide square edge casing bead, type as indicated on the Drawings. Provide joint compound treatment to conceal exposed mounting flange of bead. E. Joint Treatment Materials: 1. Joint Tapes: Plain or perforated complying with ASTM C Joint Compound: Adhesive with or without fillers complying with ASTM C Water-Resistant Joint Compound: Special water-resistant type for treatment of joints, fasteners heads, and cut edges of water-resistant backing board. Products include Sheetrock Brand W/R Compound; United States Gypsum Company. F. Sheathing: ASTM C36, Type X, 5/8 inch thick, Dens-Glass Gold Fireguard gypsum sheathing manufactured by GP Gypsum Corporation; width - 48 inches, lengths - 8, 9 and 10 feet, square edges, glass mat surfacing. G. Sheathing Fasteners: Bugle Heat ITW Buildex self-tapping screws with Climaseal finish. H. Tile Backer Board: 5/8 inch thick, Dens-Shield Fireguard, Type X manufactured by G-P Gypsum Corporation; 32 inches x 5 feet and 4 feet x 8 feet; water resistant treated core with glass mat moisture protectant coating and embedded glass mats at both sides; face side is surfaced with heat-cured copolymer water and vapor retardant coating. 3 PART THREE - EXECUTION 3.1 INTERIOR PARTITION FRAMING A. Partition Installation: 1. Stud System Erection: Attach metal runners at floor and to structural elements with suitable fasteners located 2 inches from each end and spaced at maximum of 24 inches on center. Position studs vertically, engaging floor track and runner at ceiling or structure, and spaced at 16 inches on center maximum or as otherwise indicated on drawings. Place studs in direct contact with all door frame jambs, abutting partitions, partition corners and existing construction elements. Provide double studs at all openings thru walls

5 2. Anchor all studs for shelf-walls and those adjacent to door and window frames, partition intersections, and corners to ceiling and floor runner flanges with Unimast Metal Lock Fastener tool. Securely anchor studs to jamb and head anchor clips of door or side-light frames by bolt or screw attachment. Over door and side-light frames, place horizontally a cut-tolength section of runner, with a web-flange bend at each end, and secure with one positive attachment per flange. 3. Brace studs as required above ceilings where stud height exceeds stud manufacturer's published limiting heights based on single span conditions for stud spacing indicated or specified with 5 pounds per sq. foot uniform load and limiting deflection of L/ Install diagonal stud brace above ceiling opposite strike side of door jamb. Secure to structure. 5. Install continuous horizontal stud above ceiling and fastened thru gypsum board to each stud to improve wall alignment. 6. Partitions noted to seal to underside of roof deck shall have furred offsets as required around structural members. 7. Partitions shall have furred offsets to enclose all columns. 8. Provide members to frame openings at all duct penetrations. B. Chase Wall Erection: 1. Align two parallel rows of floor and ceiling runners spaced as indicated in the drawings. Attach to concrete slabs with power driven anchors 24 inches on center and to suspend ceiling tees or structure with suitable fasteners 24 inches on center. 2. Position metal studs vertically in runners, 16 inches on center, with flanges in the same direction and with studs on opposite sides of chase directly across from each other. Anchor all studs to floor and ceiling runner flanges with USG Metal Lock Fastener tool. 3. Cut cross bracing to be placed between rows of studs from gypsum panels, 12 inches high by chase wall width. Space braces 48 inches on center vertically and attach to stud webs with six 1 inch, Type S screws per brace. If larger braces are used, space screws 8 inches on center maximum on each side. 4. Bracing of 2-1/2 inch metal studs may be used in place of gypsum panels. Anchor web at each end of metal brace to stud web with two 3/8 inch pan head screws. When chase wall studs are not opposite, install metal stud cross braces 24 inches on center horizontally and securely anchor each end to a continuous horizontal 2-1/2 inch runner screw-attached to chase wall studs within the cavity. 3.2 SUSPENDED CEILING FRAMING A. Grillage Erection: Space 8-gauge hanger wires 48 inches on center along carrying channels and within 6 inches of ends of carrying-channel runs. Wrap hanger around and through beams or joists. Install 1-1/2 inch carrying channels 24 inches on center and within 6 inches of walls. Position channels for proper ceiling height level and secure with hanger wire saddle-tied along channel. Provide 1 inch clearance between runners and abutting walls and partitions

6 Secure furring to carrying channels with clips or saddle-tie to support with at least 8 inches and securely wire-tie each end with double-strand 16 gauge tie wire. 1. Erect metal furring channels at right angles to 1-1/2 inch carrying channels or main support members. Space furring 16 inches on center and within 4 inches of walls. Provide 1 inch clearance between furring ends and abutting walls and partitions. Secure furring to carrying channels with clips or saddle-tie to supports with double strand 16 gauge tie wire. At splices nest furring channels at least 8 inches and securely wire-tie each end with double-strand 16 gauge tie wire. 2. At light troffers or any openings that interrupt the carrying or furring channels, install additional cross reinforcing to restore lateral stability of grillage. B. Metal Stud Framing System Erection: Attach runners at ceiling height through gypsum panels to each partition stud with two screws. Insert metal studs in runners and attach each end with one 3/8 inch pan head screw. Install 1-5/8 inch stud cross-bracing over stud framing, space 48 inches on center and attached to each framing stud with two 3/8" pan head screws. At hangers, install 12 inches long stud section for box reinforcing or lap studs 12 inches and secure each end with two 3/8 inch pan head screws. At light troffers or any openings that interrupt the ceiling, install additional cross reinforcing to maintain structural integrity of framing. 3.3 GYPSUM PANEL INSTALLATION A. Apply gypsum panels vertically or horizontally. Position all edges over studs for vertical application; all ends over studs for horizontal application. Use maximum practical lengths to minimize end joints. Fit ends and edges closely, but not forced together. Stagger joints on opposite side of partition. B. For single-layer vertical application of gypsum panels, space screws 12 inches on center in field of panels and 8 inches on center. Staggered along vertical abutting edges. For horizontal panel application, space screws 12 inches on center. In field and along abutting end joints. C. For double-layer screw attachment, space screws 16 inches on center. for both layers. Apply both layers of gypsum panels vertically with joints in face layer offset from base layer joints. For 5/8 inch panels, use 1 inch screws for base layer and 1-5/8 inch screws for face layers. For ½ inch panels, use 7/8 inch screws for base layer and 1-5/16 inch screws for face layer. D. Install gypsum panels to provide a minimum of ½ inch space between bottom edge of wall board and the concrete slab surface. E. Apply gypsum panels over framing to form curved surface where indicated. Multi-layers of 1/4 inch or 3/8 inch thick panels may be applied to achieve required thickness if necessary. Short radii curves may require moistening the panels with water in accordance with the manufacturers' instructions. Multi

7 layers of gypsum panels shall be laminated with adhesive as described in subparagraph F.2 below. F. Acoustical Sealant: Seal all joints, cracks and penetrations of sound rated partitions and walls to close air leaks and flanking paths for noise. 1. Seal joint at bottom edges of gypsum board panels at floor with continuous bead of sealant. 2. Seal joint at top edge of gypsum board panel at underside of roof deck with continuous bed of sealant. 3. Seal perimeter of all wall recessed outlet boxes, duct, and conduit and pipe penetrations. 4. Seal perimeter of all wall recessed fixtures. G. Accessory Application and Finishing: 1. Joint System: Finish all face panel joints and internal angles with USG Joint System installed according to manufacturer's directions. a. Mix joint cement in strict accordance with manufacturer's directions. b. Butter cement into joints filling them evenly and fully. c. Center tape and press down into cement leaving sufficient cement under tape for proper bond. Cover with thin coat of cement to fill recess between tape and board to bring material flush with surface. d. Where gypsum board will be sight exposed, apply two (2) additional layers of joint cement or topping compound to all joints and screw heads and allow drying at least 24 hours between coats. Final coat of cement shall be at least 9 inches on either side of joint with edges feathered. e. Tape and float all inside corners where gypsum board meets gypsum board. f. Face panels shall be cut fit around all wall outlets and switch boxes, utility lines, etc. All voids and cracks, occurring around all openings in board shall be taped and covered with joint cement. g. Sand smooth all joints at gypsum board where receiving paint finish or vinyl wallcovering. h. Water-Resistant Joint Compound: Special water-resistant type for treatment of joints, fastener heads, and cut edges of water resistant backing board. 2. Laminating Adhesive: Spread to provide ½ inch adhesive beads 4-1/2 inches on center for full sheet lamination. For strip lamination, apply adhesive in vertical strips of four ½ inch beads, 1-1/2 inches on center to 2 inches on center Space strips 24 inches on center. 3. Corner Bead: Reinforce all vertical and horizontal exterior corners with corner bead fastened with 9/16 inch rosin-coated staples 9 inch on center. on both flanges along entire length of bead. 4. Metal Trim: Where assembly terminates against masonry or other dissimilar material, and at conditions indicated in the drawings, apply metal trim over panel edge and fasten with screws. 5. Screws: Power-drive at least 3/8 inch from edges or ends of panel to provide uniform dimple of 1/32 inch deep

8 6. Control Joints: Cut panel at joint and back with double framing members. Attach control joint to face layer with 9/16 inch rosin-coated staples spaced 6 inches o.c. on both flanges along entire length of joint. H. Back up Steel Sheet Metal & Wood Blocking: Install minimum 16 gage, 8" high sheet metal at face of studs for display board or other wall mount device, such as toilet partitions, drinking fountains and other equipment. Also, coordinate with carpentry work to ensure installation of fire-retardant wood blocking between studs for mounting casework, millwork, etc. I. Rough-in boxes for switches and electrical outlets shall be firmly secured at both sides by cross bracing between studs. J. Flat Strap: Attach continuous flat straps at the face of stud with 2 screws each stud for wall mounted items. 3.4 GYPSUM BOARD FINISHING A. Finish all face panel joints and internal angles with joint system installed in accordance with manufacturer s instructions. B. Spot exposed fasteners on face layers and finish corner bead, control joints and trim with at least three coats of joint compound, feathered out onto panel faces and sanded smooth. C. Finish gypsum board in accordance with the recommendations of GA-214 and GA Level 0 Finish (temporary partitions to be removed prior to final occupancy): No taping, finishing or accessories required. 2. Level 1 Finish (concealed areas above ceiling): Joints and interior angles shall have tape embedded in joint compound. Surface shall be free of excess joint compound. Tool marks and ridges are acceptable. 3. Level 2 Finish (water resistant gypsum board or tile backer board serving as ceramic tile substrate): Joints and interior angles shall have tape embedded in joint compound and a separate coat of joint compound applied over joints, angles, fastener heads and accessories. Surface shall be free of excess joint compound. Tool marks and ridges are acceptable. 4. Level 3 Finish (mechanical, electrical, custodial, storage, maintenance and telephone rooms): Joints and interior angles shall have tape embedded in joint compound and two separate coats of joint compound applied over all joints, angles, fastener heads and accessories. Joint compound shall be smooth and free of tool marks and ridges. 5. Level 4 Finish (all other drywall areas scheduled for paint, fabric or vinyl wall covering): Joints and interior angles shall be tape embedded in joint compound and three coats of joint compound shall be applied over all joints, angles, fastener heads and accessories. Joint compound shall be smooth and free of tool marks and ridges

9 D. Stencil paint wall surface above ceilings to denote fire rated walls. 1. Paint color red. 2. Wording to be Fire Rated Assembly - X-Hour (X to be hour rating). 3.5 GYPSUM SHEATHING: A. Examine sub-framing, verify that surface of framing and furring members to receive sheeting does not vary more than 1/4 inch from the place of faces of adjacent members. B. Install sheathing in accordance with manufacturer s instructions and applicable instructions in GA-253 and ASTM C1280. C. Install sheathing with gold color side to the exterior. Use maximum lengths possible to minimize number of joints. D. Apply with long edges at right angles to studs with groove edges down, interlocking the tongue of previously installed panels. Joints shall occur over framing. Stagger vertical joints. E. Attach sheathing to studs with screws spaced at 8" o.c. in the field at intermediate framing and 8 inches o.c. along edges at framing supports. Locate screws at edges, 3/8 inch from edge of panel. END OF SECTION