SECTION GYPSUM BOARD PART 1 - GENERAL

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1 SECTION GYPSUM BOARD PART 1 - GENERAL 1.01 DESCRIPTION: A. Work under this section is subject to requirements of the Contract Documents including the General Conditions and Supplementary Conditions and applicable portions of Division 1 - General Requirements. B. The work consists of all labor, material and equipment necessary and required to complete all gypsum board as shown on the drawings and specified herein RELATED WORK SPECIFIED ELSEWHERE: A. Wood grounds, blocking, etc.: Section B. Suspension systems for acoustical panel ceilings: Section C. Painting: Section D. Resilient Base: Section Section E. Recessed corner guards. Section QUALITY ASSURANCE A. Gypsum Board Systems: Shall be provided by a Contractor capable of providing all components and accessories necessary, and insuring compatibility of all components for each system as shown and required. 1. Single-Source Responsibility: a. Obtain steel framing members for gypsum board assemblies from a single manufacturer. b. Obtain each type of gypsum board and other panel products from a single manufacturer. c. Obtain finishing materials from either the same manufacturer that supplies gypsum board and other panel products or from a manufacturer acceptable to gypsum board manufacturer. B. Fire-Resistant Ratings: Comply with fire-resistance ratings as indicated and as required by governing authorities and codes. Provide materials, accessories and application procedures which have been listed by U.L. or tested according to ASTM E 119 for the type of construction shown. C. Codes and Standards: Comply with applicable requirements of ANSI A97.1 and A97.2; or otherwise required by governing authorities or codes SUBMITTALS A. Manufacturer s Data: Submit copies of manufacturer s specifications and installation instructions for each component, including other data as may be required to show compliance with these specifications DELIVERY, HANDLING AND STORAGE GYPSUM BOARD

2 A Coordinate delivery and installation to minimize storage periods at the project site. Deliver in manufacturer s unopened bundles or packages, fully identified with manufacturer s name, brand, type and grade. Protect material from weather, soiling and damage using handling equipment and storage techniques recommended by the manufacturer JOB CONDITIONS A. Examination of Substrate: Examine the substrate and the conditions under which the drywall work is to be performed, and notify the Contractor in writing of any unsatisfactory conditions. Do not proceed with the installation until unsatisfactory conditions have been corrected. Start of work will evidence acceptance of conditions. B. Construction Tolerance for Gypsum Drywall Work: Shim work as required to comply with specified tolerances. Do not exceed 1/16 inch offset between planes or abutting sheets (at edges or ends). Do not exceed 1/8 inch in 8 feet, in all locations and directions SPECIAL REQUIREMENTS A. In cold weather, the building shall be heated during the application of the gypsum board and joint treatment to maintain a uniform temperature in the range of 45 degrees F to 70 degrees F, and ventilation shall be provided to eliminate excessive moisture. B. All materials specified shall be delivered on the job in original unopened containers or bundles, and stored in a place free from damage and exposure to the elements. C. Directions for the installation and application of all materials shall be in accordance with the manufacturer s latest printed directions. PART 2 - PRODUCTS 2.01 GYPSUM BOARD A. Shall meet the requirements of ASTM C 473. Panels shall be of thickness indicated on drawings; shall have tapered edges and shall be of types suitable for conditions of use and as follows: 1. Gypsum Board: Shall meet the requirements of ASTM C Gypsum Backing Board: Shall meet the requirements of ASTM C Moisture Resistant Gypsum Board: Shall meet the requirements of ASTM C Type X Gypsum Board: Shall be gypsum board which provides greater fireresistance; shall be gypsum board or gypsum backing board or moisture resistant gypsum board METAL STUDS A. Shall be manufacturer s standard type and shall be of sizes indicated; shall meet ASTM C645; shall be fabricated from 20 gauge galvanized steel, except as otherwise shown on drawings. Studs shall be C shape, screw type; shall be complete with all accessories required for installation indicated. Deflection requirement shall be L/ TRACK A. Shall be manufacturer s standard floor or ceiling track; shall be of sizes required by metal studs. Track shall be fabricated from 20 gauge galvanized steel, except as otherwise shown on drawings FASTENERS A. Shall be of kind, type, and size recommended by gypsum drywall manufacturer for the application GYPSUM BOARD

3 shown and specified. Fasteners in fire-rated assemblies shall be spaced and installed in strict accordance with the rating as referenced and tested CHANNELS A. Shall be formed from cold-rolled galvanized steel, free from rust, and shall be of the following minimum weights: 1. 3/4 inch, 300 pounds per 1000 linear feet /2 inches, 475 pounds per 1000 linear feet FURRING CHANNELS A. Shall be as recommended by the gypsum board manufacturer TIE WIRE A. Shall be 18 or 16 gauge, galvanized HANGER WIRE A. Shall be 8 gauge, galvanized JOINT COMPOUND A. Shall be with or without fillers complying with ASTM C 475. Provide in dry powder form or premixed ready for application. No compound shall contain asbestos. Provide either type of joint compound as follows: 1. Single Compound: Provide manufacturer s single component compound suitable for both bedding and finishing of joints. 2. Two-Compound: Provide compatible joint compounds, one compound being suitable for bedding, and the other compound suitable for finishing of joints JOINT TAPES A. Shall be plain, complying with ASTM C ADHESIVE A. Shall be as recommended by the gypsum board manufacturer for the application shown and specified SEALANT A. Shall be a non-drying, non-shrinking, non-migrating type recommended by the gypsum drywall manufacturer. Provide paintable type sealant wherever exposed to view SOUND INSULATION A. Shall be mineral fiber or glass fiber blanket type insulation, 3 inches thick, unless otherwise shown on drawings WATER-RESISTANT JOINT COMPOUND A. Water-resistant type for treatment of joints, fastener heads and cut edges of moisture-resistant board, as recommended by gypsum board manufacturer CORNER BEADS AND EDGE BEADS GYPSUM BOARD

4 A. Shall be fully concealed at all gypsum board corners and edges; shall be of type recommended by gypsum board manufacturer. PART 3 - EXECUTION 3.01 EXAMINATION A. Examine substrates to which drywall construction attaches or abuts pre-set hollow metal frames, cast-in-anchors, and structural framing, with installer present for compliance with requirements for installation tolerances and other conditions affecting performance of drywall construction. Do not proceed with installation until unsatisfactory conditions have been corrected PREPARATION A. Ceiling Anchorages: Coordinate installation of ceiling suspension systems with installation of overhead structural system to ensure that inserts and other structural anchorage provisions have been installed to receive ceiling anchors in a manner that will develop their full strength and at spacing required to support ceiling. 1. Furnish inserts and other devices indicated to other trades for installation well in advanced of time needed for coordination with other construction. B. Where offset anchor plates are required provide continuous units fastened to building structure not more than 24 inches o.c. and to ceiling runners INSTALLATION - METAL STUDS AND TRACK A. Metal studs and all required accessories shall be installed in accordance with manufacturer s printed instructions and recommendations, unless otherwise indicated. B. Install continuous tracks sized to match studs. Secure tracks as recommended by the stud manufacturer for the type of construction shown, except do not exceed 24 inches on centers spacing for nail or power-driven fasteners, nor 16 inches on centers for other types of attachment. Provide fasteners at corners and ends of tracks. C. Where metal stud partitions abut ceiling or deck construction or horizontal structural elements, provide slip or cushion-type joint between stud, partition and structure as recommended by stud manufacturer to prevent the transfer of structural loads or movements to studs. D. Set studs plumb, except as needed for diagonal bracing or required for non-plumb walls or warped surfaces and similar requirements. E. Where stud partition abuts structural columns or walls, including masonry walls, anchor ends of stiffeners to supporting structure. F. Install supplementary framing, blocking and bracing in the metal stud partition wherever walls or partitions are indicated to support fixtures, equipment, services, trim and furnishing, or similar work requiring attachment to the wall or partition. Where type of supplementary support is not otherwise indicated, comply with the stud manufacturer s recommendations and industry standards in each case, considering the weight or loading resulting from the item supported. G. Friction fit studs to tracks by positioning and rotation into place. Provide positive attachment to tracks for studs located at partition corners and intersections, and adjacent to openings, and for jack studs located above and below openings. Attach with either self-tapping screws or by use of clinching tool, at both flanges of stud. H. At corners and intersections, provide a minimum of 3 studs, positioned to support each surface of partition; or provide 2 studs with the second stud installed after the base course of gypsum board has been run through, and screw anchor the second stud through the gypsum board to the first stud at 2 inches on center spacing. GYPSUM BOARD

5 I. Additional studs shall be provided at each door frame. Unless shown otherwise, this shall consist of two 20 gauge studs at each jamb and one additional stud located within 6 inches of each jamb stud. Fasten studs to frames in accordance with manufacturer s recommendations. Spot grout at each jamb anchor clip at all metal frames. J. Install full length studs between tracks wherever possible. If necessary, splice studs by nesting with a minimum lap of 8 inches and fasten laps with 2 screws through each flange. K. Install continuous horizontal stiffeners in stud partitions indicated to receive gypsum board on one side only. Space stiffeners 4 feet 6 inches on centers (vertical distance); wire-tie at each stud intersection, and secure ends at partitions and jamb studs, and at abutting construction. L. Except as otherwise indicated, space studs at 16 inches on centers. M. Sound insulation shall be provided where shown in conjunction with partitions, and shall be installed in accordance with manufacturer s recommendations INSTALLATION - FURRING CHANNELS A. Unless otherwise recommended by gypsum board manufacturer, furring channels shall be screw type, installed 24 inches on centers vertically. Frame openings, cutouts and corners with channel furring as required to support edges or ends of gypsum board. Attach channels to walls in accordance with gypsum board manufacturer s recommendations and ANSI A INSTALLATION - CEILINGS A. Space 8 gauge hanger wires 48 inches on centers along carrying channels and within 6 inches of ends of carrying-channel runs. In concrete, anchor hangers by attachment to reinforcing steel, by loops embedded at least 2 inches or by approved inserts. For steel construction, wrap hanger around or through beams. B. Additional hangers shall be provided at fixtures as required to prevent deflection of suspension system members. Also, additional hangers shall be provided where required to support other work resting in or on the ceiling except for unusual concentrated or heavy loads. C. Install 1-1/2 inches carrying channels 48 inches on centers (24 inches for fire-rated construction) and within 6 inches of walls. Position channels for proper ceiling height, level, and secure with hanger wire saddle tied along channels. Provide 1 inch clearance between runners and abutting walls and partitions. At channel splices, interlock flanges, overlap ends 12 inches and secure each end with double-strand 18 gauge tie wire. D. Erect metal furring channels at right angles to 1-1/2 inch carrying channels. Space furring within 6 inches of walls. Provide 1 inch clearance between furring ends and abutting walls and partitions. Attach furring channels to 1-1/2 inch channels with furring channel clips installed on alternate sides of carrying channel. Saddle-tie furring to channels with double-strand 16 gauge tie wire when clips cannot be alternated. At splices, nest furring channels with at least 8 inches overlap and securely wire-tie each end with double-strand 18 gauge tie wire. E. At light troffers or any openings that interrupt the carrying or furring channels, install additional cross-reinforcing to restore the lateral stability of grillage. F. Ceiling layouts shall be coordinated with other work that penetrates or is supported by the ceiling suspension system. Additional framing shall be provided as required to form openings and to frame for recessed lighting fixtures and the like. G. Where ceilings are components of floor-ceiling or beam assemblies for which a fire-resistance rating is shown or required, provide complete ceiling systems complying with the requirements of governing authorities and codes for the construction assemblies shown. H. Unless shown otherwise, control joints in ceilings shall be located as recommended by the gypsum drywall manufacturer. GYPSUM BOARD

6 I. Where metal decks occur the type and location of attachments shall be such that hangers shall not be supported directly from metal deck. Additional hangers shall be provided at fixtures as required to prevent deflection of suspension system members. Also, additional hangers shall be provided where required to support other work resting in or on the ceiling except for unusual concentrated or heavy loads INSTALLATION - GYPSUM BOARD A. Proceed with installation of gypsum board when framing deficiencies are corrected and surfaces to receive gypsum board are acceptable. B. Unless otherwise shown or specified, install gypsum board, including accessories, in accordance with manufacturer s printed instructions. C. All gypsum board work shall extend to underside of construction above unless specifically shown otherwise. All fire-rated gypsum board partitions shall be constructed to underside of floor or roof structure above. D. Gypsum board at partitions shall be applied vertically using panels of such lengths as will preclude horizontal joints, as much as possible, in exposed gypsum board surfaces. All single layer and double layer work shall be screw attached to studs. E. Use boards of maximum lengths to minimize end butt joints. Where unavoidable, locate end butt joints as far from center of walls or ceilings as possible, and stagger not less than 1 foot in alternate courses of board. F. Install gypsum board with face side out. Do not install imperfect, damaged, damp or wet gypsum board. Butt boards together for a light contact at edges or ends with not more than 1/16 inch open space between boards. Do not force into place. G. Where sound-rated drywall work is indicated (STC rating), including double-layer work and work on resilient furring, seal the work at perimeters, control and expansion joints, openings and penetrations with a continuous bead of acoustical sealant including a bead at both faces of partitions. Comply with manufacturer s recommendations for location of beads, and close off sound-flanking paths around or through the work, including sealing of partitions above acoustical ceiling. H. Locate edges or end joints over supports, except in horizontal applications or where intermediate supports or gypsum board back-blocking is provided behind end joints. Position boards so that like edges abut, tapered edges against tapered edges and mill-cut or field-cut ends against mill-cut or field-cut ends. Do not place tapered edges against cut edges or ends. Stagger vertical joints over different studs on opposite sides of partitions. I. Attach gypsum board to framing and blocking as required for additional support at openings and cutouts. J. Form control joints and expansion joints with space between edges of boards, prepared to receive trim accessories. K. Accurately measure and precut gypsum board units prior to installation. Make all cuts from face side by scoring and snapping away from face side or by sawing. Completely cut paper on back face; do not break paper by tearing. Maintain close tolerances for accurate fit at joints between sheets and at frame openings, and allow for covering of edges of cutouts with plates and escutcheons. Cut edges smooth as required for neat and accurate fit. L. Do not locate joints within 8 inches of corners or openings. Wherever possible cut boards so that a single vertical joint occurs over center of openings. M. At partitions and walls, provide continuous beads of sealant at juncture of both faces of runners or plates with floor and walls. Seal prior to installation of drywall boards. N. At openings and cutouts, fill open space between gypsum board and fixtures, ducts and other flush GYPSUM BOARD

7 or penetrating items, with continuous bead of sealant. O. Seal sides and backs of electrical boxes to completely close up openings and joints. Apply acoustical sealant to seal perimeters and penetrations of all sound-rated partitions. At fire rated walls and ceiling, seal sides of electrical boxes between wallboard and box with fire stop sealant (specified in Section 07270). P. Begin fastening from center portion of sheet and work toward edges and ends. Insure contact of gypsum board with supports by applying pressure on surface adjacent to fastener being driven. Do not located fasteners closer than 3/8 inch from edges or ends of panels. Drive with shank approximately perpendicular to gypsum board surface. Q. On furred exterior wall applications, do not allow fasteners to penetrate through furring and contact masonry. R. Drive screws with power screwdriver recommended by gypsum drywall manufacturer. Do not hammer screws. Set screw heads slightly below surface of board but do not break or strip paper face around the screw. Stagger screws on edges and ends of adjacent panels. S. After installation of gypsum board, check for loose fasteners, and if detected, drive tight. Where paper face is torn or punctured, install another fastener approximately 1-1/2 inches away and remove faulty fastener. T. Unless shown otherwise, a control joint shall be provided wherever a partition or furring run exceeds 30 feet and shall be extended from the corner of an assembly (i.e. door, window) to the full height of the wall. U. All joints, screw head and other depressions in the surface or the gypsum board shall be treated in accordance with the joint system manufacturer s recommendations. V. All external angles formed by the intersection of either gypsum board surfaces or other surfaces shall be treated with metal trim. W. Where so shown, gypsum board panels shall be laminated directly to masonry. Adhesive used and method of installation shall be as recommended by gypsum board manufacturer. X. Double-Layer Application: Install gypsum backing board for base for base layers and gypsum wallboard for face layers. 1. On partitions and walls apply base layers and face layers vertically (parallel to framing) with joints of base layers located over stud or furring member and face layer joints offset at least one stud or furring member with base layer joints. Stagger joints on opposite sides of partitions. Y. For trim accessories with back flanges, fasten to framing with the same fasteners used to fasten gypsum board. Otherwise, fasten trim accessories according to accessory manufacturer s directions for type, length, and spacing of fasteners. 1. Install corner guards and end guards at external corners and ends of partitions ACCESSORY INSTALLATION A. Provide control joints within the following parameters: 1. Partitions, 30 feet maximum in either direction. 2. Interior ceilings with perimeter relief, 50 feet maximum in either direction. 3. Interior ceilings without perimeter relief, 30 feet maximum in either direction. 4. Gypsum construction should be isolated with control joint as follows: GYPSUM BOARD

8 a. Where partitions or ceilings of dissimilar construction meet and remain in the same or similar plane. b. Where wings of L, U, and T shaped ceilings are joined. c. Where expansion or control joints occur in the base wall construction and building structure. d. At intersection of columns through ceilings. e. Above and below (as applicable) one or both sides of any wall opening. 5. Ceiling-to-floor door or window frames can be used as vertical control joints. 6. Less than ceiling-to-floor height door or window frames can be used if control joints extend to ceiling and wall framing at the header is done properly to allow the joint to operate as intended. 7. Provide separate supports for each flange of the control joint. 8. If gypsum board continues above ceiling, control joint should continue also. 9. Consult with the Architect, prior to framing, to finalize control joint locations required by parameters listed here, but not indicated on the drawings CHASE WALL FRAMING A. Align 2 parallel rows of floor and ceiling track according to partition layout. Spacing between outside flanges of each pair of tracks must not exceed 24 inches. Follow instructions above for attaching tracks. B. Position steel studs vertically in tracks, 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 track flanges with metal lock fastener or 3/8 inch Type S pan head, hex washer head, or 1/2 inch lowprofile type head screws. C. Cut cross-bracing to be placed between rows of studs from gypsum board 12 inches high by chase wall width. Space braces 48 inches on centers vertically and attach to stud web with six 1 inch Type S screws per brace. If larger braces are used, space screws 8 inches on centers maximum on each side. D. Bracing of 2-1/2 inches minimum steel studs may be used in place of gypsum board. 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 steel stud cross-braces 24 inches on centers horizontally, and securely anchor each end to a continuous horizontal 2-1/2 inches track screw-attached to chase wall studs within the cavity SOFFIT INSTALLATION A. Braced Soffit: Attach steel tracks to ceiling and side wall, placing fasteners close to outside flange of track. On stud walls, space fasteners to engage stud. Fasten vertical gypsum face board to web of face corner track and flange of ceiling with Type S screws spaced 12 inches on centers. Place screws in face corner track at least 1 inch from edge of board. Insert steel studs between face corner track and sidewall track and attach alternate studs to tracks with metal lock fastener or screws. Attach bottom face board to studs and track with Type S screws spaced 12 inches on centers. Attach corner bead and finish INSTALLATION SHAFT WALL: A. Unless shown or specified otherwise, all work for fire-resistant gypsum wallboard partitions for enclosing shafts shall be in accordance with the printed literature and recommendations of the GYPSUM BOARD

9 gypsum wallboard manufacturer GYPSUM BOARD FINISHING A. Use joint tape to reinforce joints formed by tapered edges or butt ends of gypsum boards and at interior corners and angles. Set tape in joint compound and apply skim coat over tape in one application. Do not use topping or finishing compounds for setting to tapes. B. Where open spaces of more than 1/16 inch in width occur between abutting board units, except at control joints and expansion joints, prefill joints with joint compound and allow prefill to dry before application of joint tape. C. Reinforce external corners of gypsum board work with required type of corner bead. Securely fasten metal corner beads as recommended by manufacturer. Use fasteners which will be fully concealed by joint compound fill applied over flanges. D. Provide metal casing bead trim, where shown. Install in single unjoined lengths unless run exceeds longest available stock length. E. Coordinate installation of trim with gypsum board installation where type of trim or application requires installation of trim prior to, or progressively with, installation of gypsum board APPLICATION OF JOINT COMPOUNDS A. Do not use joint compounds if recommended pot-life time has expired. Allow drying time between applications of joint compound in accordance with manufacturer s recommendations for the relative humidity and temperature levels at the time of application. In no case, allow less than 24 hours drying time between application of joint compound. Apply not less than 3 separate coats of joint compound over joints, fastener heads and metal flanges. B. Joint compound treatment is not required above suspended ceilings COORDINATION A. The work shall be coordinated with the work of the Plumbing, Heating, Ventilating, Fire- Protection and Electrical Trades. In addition, such items shall be furnished by others and installed under this section as follows: 1. Adapter rings for gypsum board ceilings or walls, where required. 2. Metal access panels PROTECTION OF WORK A. Installer shall advise Contractor of required procedures for protecting gypsum board work from damage and deterioration during remainder of construction period. END OF SECTION GYPSUM BOARD

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