SECTION GYPSUM WALLBOARD. A. PART A and DIVISION 1 of PART B are hereby made a part of this SECTION.

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1 SECTION PART 1 GENERAL 1.01 GENERAL REQUIREMENTS A. PART A and DIVISION 1 of PART B are hereby made a part of this SECTION. B. Examine all conditions as they exist at the project prior to submitting a bid for the work of this SECTION SCOPE OF WORK A. Furnish and install the following items required to complete the work of this SECTION, as shown on the Drawings and specified herein. 1. Metal stud interior partition framing, including screw studs, stud tracks, bracing, gypsum board, control joints and accessories. 2. Suspended gypsum board ceilings and soffits including metal hangers, metal studs, carrying channels, furring channels, and gypsum board. 3. Drywall construction system for backing exterior face masonry veneer, including steel screw studs, stud tracks, gypsum wallboard, glass faced sheathing, and all related items. 4. Gypsum board, applied to wood or metal studs and blocking as shown on the drawings. 5. Drywall construction for various furring conditions indicated on the Drawings, including, as applicable metal furring channels, steel screw studs, stud tracks, and gypsum wallboard. 6. Cement backer board for ceramic tile wainscot and exterior rainscreen systems. 7. Abuse resistant gypsum wall board for corridors to eight feet above finish floor, in stairwells and in other heavy use areas as shown on the drawings. 8. All metal and flexible accessories (including but not limited to edge trim, beads, control joints, expansion joints, etc.) required in conjunction with the various gypsum board conditions indicated on the Drawings. 9. Internal metal struts, bracing, supplementary framing, and reinforcing, as required to ensure complete stability within the various drywall construction systems

2 10. All additional supplementary framing and bracing required for the support of concentrated loads imposed by light fixtures, access panels and other items indicated to be attached to, or hung from, gypsum board surfaces, except where indicated to be wood. 11. Compressible filler between stud tracks of interior partitions and adjacent surfaces. 12. Tape-joint finishing system for gypsum board surfaces including above finish ceilings. 13. Acoustical sealant, bead applied to legs of stud tracks of interior partitions, prior to application of gypsum board and where else indicated on the Drawings. 14. Firesafing and smoke stopping insulation where indicated on the Drawings. 15. All metal stud framing, furring, reinforcing, bracing, accessories and fastening systems shown on the drawings, unless otherwise specified. 16. Gypsum board shaft wall system, including gypsum liner panels and metal C-H studs and accessories. 17. Metal stud framing for cafeteria platform floor. C. This subcontractor shall furnish, install, and maintain in a safe, adequate condition all staging and scaffolding that are necessary for the proper execution of the work of this SECTION ITEMS TO BE INSTALLED ONLY A. Install the following items furnished under the designated sections: 1. Access panels occurring in gypsum wallboard surfaces: By trade requiring same. 2. Installation of anchor clipping for metal door frames provided under SECTION HOLLOW METALWORK. 3. Unless otherwise noted, all insulation indicated within the stud systems for drywall construction, above soffits and ceilings: SECTION INSULATION 1.04 RELATED WORK SPECIFIED ELSEWHERE A. The following related work is to be performed under the designated SECTIONS: 1. Painting of gypsum board: SECTION PAINTING

3 1.05 SUBMITTALS 2. Wood furring, wood studs and framing, cafeteria platform subfloor blocking for attachment of items to wall and ceiling construction, and other rough carpentry: SECTION ROUGH CARPENTRY. 3. Unless otherwise noted, woodwork, including plywood sheathing, indicated in conjunction with gypsum board: SECTION FINISH CARPENTRY. 4. Through-wall flashing at exterior masonry veneer: SECTION MASONRY. 5. Continuous air barrier: SECTION AIR AND VAPOR BARRIERS. 6. Metal girts and framing for prefinished exterior wall panels SECTION PREFORMED CLADDING. A. Submit complete shop drawings in accordance with the requirements of SECTION SUBMITTALS. B. Shop drawings shall include a complete layout and design calculations for exterior drywall back-up system, for light gauge joists, and for interior partitions and suspended stud construction, etc., prepared and stamped by a structural engineer registered in the Commonwealth of Massachusetts. Shop drawings shall include stud arrangement, stud gauges and sizes, bracing, reinforcing and connection details. Indicate type, grade and manufacturer of all materials intended to be used. C. Submit the following samples in accordance with the requirements of SECTION SUBMITTALS. 1. Metal stud - 12 inch length in each size and gauge required. 2. Gypsum wallboard - 4x6 inches, minimum, in each specified type and thickness. 3. Gypsum sheathing - 4x6 inches, in each specified type and thickness. 4. Cement backer board - 4x6 inches, minimum, in each specified thickness. 5. Metal accessories - 6 inch length of each type. 6. Caulking and sealant materials - complete data, no physical samples required. 7. Compressible filler - 6x6x1 inch thick, of specified type. D. Construct up to two separate 4 foot by 8 foot sample panels of gypsum board/metal stud back-up construction for masonry veneer sample panels

4 PART 2 PRODUCTS 2.01 MATERIALS A. General - To establish a standard of quality and design desired, Specifications are based on drywall system members, as manufactured by U.S. Gypsum Company, with sealant manufactured by Tremco, and insulation manufactured by Owens Corning Fiberglass. Similar systems and materials, manufactured by National Gypsum Company, Georgia Pacific, and Bestwall, will be considered for approval as an equal by the Architect, upon receipt of adequate supporting data, and samples. B. Studs, tracks, and joists - USG galvanized steel screw studs with matching floor and ceiling tracks, in sizes indicated on the Drawings. Gauges shall be in accordance with the requirements of the GYPSUM CONSTRUCTION HANDBOOK (latest edition) as printed by U.S.G., with a minimum of 16 gauge at exterior drywall backup system, a minimum of 20 gauge at jambs of interior door openings, 20 gauge x 8 inches deep at joists, and a minimum of 25 gauge at interior partitions. Studs at exterior wall backup system shall be 6 inches wide, and a minimum of 1-5/8 inches deep. 1. Minimum structural requirements for drywall construction system backing exterior face masonry veneer are as follows: a. Wind loading - 36 PSF Saliant corners 25 PSF Typical b. Stud design for deflection - L/600 non-composite. 2. Minimum structural requirements for interior stud systems supporting gypsum wallboard finish is as follows: a. Interior loading - 5 PSF typical b. Stud design for deflection - L/ Minimum structural requirements for light gauge floor joists supporting plywood flooring shall be 150 psf live load. 4. Provide multiple jamb studs (two minimum) at each side of all openings in exterior drywall back-up system. The approximate number of additional studs at each side shall be equal to 1/2 the number of studs interrupted by the opening, or as required by actual design. a. Provide extended-leg slip tracks at the tops of exterior drywall back-up system when attaching to the building structure. Slip tracks shall allow the structural to deflect vertically without bearing on the exterior wall members, but shall resist all lateral loads imposed on them by these members. Provide sliptrack reinforcing at built up jambs as required by actual design

5 5. In the event of conflict among contract drawings, contract specifications, and referenced standards, the most stringent requirements shall govern. C. Gypsum board: 1. USG Sheetrock Brand Firecode 'C' Gypsum, 5/8 inch thick or as otherwise indicated on the drawings. 2. USG Regular Sheetrock Wallboard, 5/8 inch thick, with tapered edges. 3. GP Dens-Glass Gold, glass faced gypsum sheathing 1/2 inch thick, tongue and groove, 4ʼx8ʼ panels. 4. USG Durock Brand cement board - 5/8 inch thick, for behind all ceramic tile wainscot. 5. USG W/R gypsum panels, 5/8 inch thick, with tapered edges for all toilet rooms and kitchen areas. 6. USG shaft wall liner panels, 1 inch thick. 7. USG sheetrock abuse resistant panels, 5/8 inch thick, where noted on the drawings. (GWB II) 8. US Architectural Products, Inc., Fiber-reinforced cement backer board 9/16 cem-steel board or approved equal. D. Caulking and sealant materials: 1. For penetrations in wallboard surfaces, and exposed-to-view joints between drywall accessories and dissimilar materials - DAP Latex Caulk, Pecora AC-20 Latex. 2. Polymer Caulk, or approved equal, in colors as selected by the Architect. 3. For application to legs of stud tracks, and concealed from view joints between gypsum board and dissimilar materials - Gold Bond Acoustical Sealant or Tremco Acoustical Sealant. E. Compressible Filler - Between stud tracks and adjacent construction Fiberglass Noise Stop Board, 1/2 inch thick. F. Suspension System for Gypsum Board and Sheathing Ceilings and Soffits: 1. Hangers - Galvanized steel wire, No. 8 gauge. 2. Carrying Channels - 1-1/2 inch channels, weighing 475 pounds per thousand lineal feet, primed with rust-inhibitive paint, or where specifically indicated on the Drawings, metal studs, as herein before specified. 3. Furring Channels - USG Screw Furring Channels (used in conjunction with carrying channels only)

6 4. Furring Channel Clips - Wire type, as provided by the manufacturer of the channels. G. Channels for Furring - USG RC-1 Resilient Channels, Sheet Rock Z-furring channels, and Unimast furring channels, as shown on the Drawings and as required by the various construction conditions. H. Fasteners: 1. For single layer gypsum board to wood receiving members and metal studs and furring channels, and for first layer board of double layer application - Self-drilling Phillips bugle head, one inch long. 2. For stud tracks to concrete - Ramset or Phillips power-actuated fasteners. Concrete stub nails may be used for securing floor tracks. 3. For securing hangers to concrete overhead - Ramset or Phillips poweractuated eye pin anchors. 4. For securing hangers to metal overhead - Nelson acoustical stud welds. 5. For stud tracks to metal members - Spot welds or screws spaced as recommended by the manufacturer to assure a rigid installation. 6. For gypsum sheathing to metal studs - Self drilling Phillips bugle head, galvanized, 1-1/4 inches long. 7. Fasteners for exterior wall backup system shall be as follows: I. Accessories: a. All fasteners connecting light gauge members and accessories shall be a minimum of No. 10 size having a minimum diameter of inches. b. All fasteners connecting light gauge members to structural steel shall be power driven fasteners of 5/32 inch diameter minimum 16 inches on center maximum. All fasteners of light gauge members to concrete shall be power driven fasteners of 5/32 inch diameter minimum with a minimum of 1-1/4 inch embedment 16 inches on center maximum. 1. Casing beads - USG #801 A and B, 5/8 inch size, 1 1/4 inch expanded flanges. 2. Corner beads - USG Beads #800, galvanized, 1/8 inch ground, 1-1/4 inch by 1-1/4 inch expanded flanges. 3. Control joints - USG No. 093, roll - form zinc. J. Joint Tape Treatment (WALLBOARD) - USG self-adhering fiberglass mesh with compound recommended by the manufacturer for the particular application conditions

7 K. Fire safing - Thermafiber safing insulation with clips and fire stop sealant/compound, in configurations to suit job conditions per reference standards. L. USG C-H studs and accessories, 2 1/2 inches deep and 6 inches deep. M. Acoustic Stud Sway Brace Clips Mason Industries Inc., Hauppauge NY, Type WIC-1, neoprene pad/interlocking clip type, 3/4 inch high by 1 1/2 inch wide. N. Expansion Joint C/S Group, gasket color as selected by architect. 1. Straight wall joint FWF Wall corner joint FWFC Furnish and install fire rated expansion joints where shown on the drawings

8 PART 3 EXECUTION 3.01 ERECTION PROCEDURES A. General - Erection procedures for the various drywall construction conditions, as set forth in the published specifications of the U.S. Gypsum Company, latest editions for the various system types, shall govern this work, with the additional requirements specified hereunder and indicated on the Drawings PARTITIONS, CEILING, FASCIAS, SOFFITS AND FURRED AREAS A. Refer to the Drawings for various conditions and details of the work of this SECTION. B. Coordinate the installation work with that of related trades, in particular the work of SECTION ROUGH CARPENTRY for proper installation of wood supporting members within drywall. C. Apply a continuous bead of specified sealant to receiving legs of stud tracks, in interior partitions, prior to installing gypsum board thereon. D. Install corner beads at all external corners of gypsum wallboard, and casings wherever gypsum wallboard abuts a dissimilar material. Use tape joint treatment for internal corners, for all joints. E. Install control joints where indicated on the Drawings, and as recommended by the gypsum wallboard manufacturer, not exceeding 30 feet on center. Install fire safing at control joints in rated walls, and where shown in the Drawings. F. Caulk around all items which penetrate gypsum wallboard including electrical receptacle boxes, witch boxes, piping, and the like. G. Provide cased and reinforced openings for all major items penetrating the gypsum board surfaces. H. Furnish and install cross bracing, knee braces, and other internal reinforcing, as required to assure a completely rigid assembly on gypsum board faced partitions, ceiling, and fascias, as per the gypsum wallboard system manufacturer's recommendations, whether or not such bracing has been indicated on the Drawings. I. Install access panels, occurring in gypsum board surfaces, which are furnished by trades requiring same, securing the flanges of the panels as recommended by the manufacturer. J. Install compressible filler between stud tracks and adjacent construction in locations indicated on the Drawings. K. Install double 20 gauge studs at door openings, as shown on the drawings

9 L. At door and window openings, cut gypsum wallboard and lath to fit around openings with joints centered above openings, not at corners EXTERIOR WALL BACK-UP ERECTION PROCEDURES A. Studs and Runners 1. Align runners accurately according to exterior wall layout and secure to base and head with power-driven fastener spaces as per manufacturer's technical data. 2. Positions studs vertically in runners and space no greater than 16 inches on center. Securely anchor each stud to runner with four No. 10 1/2 inch Type S-12 Low-Profile Head Screws, two at top and two at bottom, with one screw in each flange. 3. For the slip track system, allow 1/2 inch to 3/4 inch clearance between top of studs and UR-runner. Do not fasten studs to UR-runner. Install 1-1/2 cold-rolled channel bridging within 10 inches to 12 inches of tops of studs. Connect bridging to each stud using welded or screw-attached USG Clip Angle. 4. Bridging of studs shall be provided at slip tracks (as described above) and according to the following schedule: B. Exterior Sheathing a. Walls up to 10 ft. height: One row bridging at mid-height. b. Walls over 10 ft. height: Bridging rows equally spaced, not to exceed 5 ft. on center. 1. Glassmat Faced Sheathing Install at backup construction for aluminum and masonry veneer. Install per manufacturerʼs instructions, using recommended fasteners and spacing. Coordinate installation with air and vapor barrier requirements ACCESSORY APPLICATION A. Gypsum Panel Joints - Finish all face layer joints and internal angles with a U.S. Gypsum Joint System installed according to manufacturer's directions. Panel joints above finish ceilings shall have joints finished by this SECTION Spot exposed fasteners on face layers and finish corner bead, control joints and trim as required, with at least three coats of joint compound, feathered out onto panel faces. Sand lightly between coats and following the final application of compounds to provided a smooth surface ready for painting. Do not roughen face paper when sanding. B. Corner Bead - Reinforce all vertical and horizontal exterior corners with corner bead fastened with screws or staples 9 inches o.c. on both flanges along entire length of bead

10 C. Casing Bead Trim - Where wall terminates against masonry or other dissimilar material, apply metal trim over face layer edge and fasten with screws or staples spaced 9 inches o.c. D. Screws - Power-drive at least 3/8 inch from edges or ends of gypsum panels to provide uniform dimple 1/32 inch deep. In gypsum base, set flush with surface without tearing face paper. E. Control Joints and expansion joints - Break face layer behind joint. Attach control joint to face layer with staples spaced 6 inches o.c. on both flanges along entire length of joint. F. Finishing Fasteners - Apply a taping, all-purpose type or ready-mixed Plus 3 compound to fastener depressions as the first coat. Follow with a minimum of two additional costs of topping or all-purpose compound, leaving all depressions level with the surface. (Exception: ready-mixed Plus 3 Compound needs only one additional coat.) G. Finishing Beads and Trims 1. Apply first coat to all bead and trim and properly feather out from ground to plane of surface. Compound must thoroughly dry prior to application of second coat. (Exception: Durabond joint compounds need only have hardened prior to application of next coat). 2. Apply second coat in same manner as first coat, extending compound slightly beyond onto face of panel. Compound must be thoroughly dry prior to application of finish coat. 3. Apply finish coat to all bead and trim, extending compound slightly beyond the second coat and properly feathering from ground to plane or surface. (Exception: Only two coats of ready-mixed Plus 3 Compound are needed). Sand finish as necessary to provide a flat smooth surface ready for decoration. When sanding take care not to roughen face paper. H. Column covers 1. Install true, plumb, and level with fasteners and clips per manufacturerʼs recommendations. 2. Tape and finish joint in accordance with gypsum board finish manual, taking core to minimize crowning CUTTING AND PATCHING A. When so directed by the Architect, and prior to any painting of gypsum board surfaces, check all drywall throughout the work, doing any and all cutting, patching, and joint treatment required in a manner satisfactory to the Architect

11 3.06 PROTECTION AND CLEANING A. During the operation of drywall work, protect the work of other trades against undue soilage and damage by the exercise of reasonable care and precautions. Repair and/or replace any work so damaged and soiled SHAFT WALL SYSTEM A. Position steel runners at floor and ceiling with the short leg toward finish side of wall. Securely attach runners to structural supports with power driven fasteners at both ends and maximum 25 inches on center. B. Cut liner panels 1 inch less than floor-to-ceiling height and erect vertically between J-Runners. Where shaft walls exceed maximum available panel height, position liner panel end joints within upper and lower third points of wall. Stagger joints top and bottom in adjacent panels and reinforce end joints with horizontal C-H stud. Screw-attach studs to runners on walls over 16 feet high, if applicable. C. Use steel C-H studs 3/8 inch to not more than 1/2 inch less than floor-to-ceiling height, and install between liner panels with liner inserted in the groove. Install full-length steel E-Studs or J-Runners vertically at T-intersections, corners, door jambs, and columns. Install full-length E-studs over gypsum liner panels at both sides of closure panels. Frame openings cut within a liner panel with J-Runner around perimeter. For openings, frame with vertical E-Stud or J-Runner at edges, horizontal J-Runner at head and sill, and reinforcing as shown on the drawings. Suitably frame all openings to maintain structural support for wall. D. Install floor-to-ceiling steel J-Runners or E-Studs each side of steel hinged door frames to act as strut-studs. Attach strut-stud to floor and ceiling runners with two 3/8 inch Type S-12 Pan Head Screws. Attach strut-studs to jamb anchors with 1/2 inch Type S-12 screws. Over steel doors, install a cut-to-length section of J- Runner and attach to strut-studs with 3/8 inch Type S-12 Screws. E. For double-layer finish, apply base layer 1/2 inch Sheetrock Brand Firecode "C" Panel vertically one side of studs. Fasten base layer to studs with 1 inch Type S Screws 24 inches on center. Caulk perimeter of base layer. Apply 1/2 inch Sheetrock Brand Firecode "C" Gypsum Panel face layer vertically over base layer with joints staggered and attached with 1-5/8 inch Type S. screws staggered from those in base, spaced 12 inches on center and driven into studs and runners. END OF SECTION