1. Section : Rough Carpentry 2. Section : Exterior Insulation and Finishing Systems 3. Section : Metal Roof Panels

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1 SECTION SHEATHING PART 1 GENERAL 1.1 SUMMARY A. Section includes: 1. Roof and Wall Sheathing. B. Related Sections: Documents relating to the work of this section include, but are not limited to, the General Conditions, Supplementary Conditions, Sections of Division 1, and: 1. Section : Rough Carpentry 2. Section : Exterior Insulation and Finishing Systems 3. Section : Metal Roof Panels 1.2 REFERENCES (Refer Section ) A. Provide products and workmanship in accordance to: 1. American Plywood Association (APA) 2. American Wood Preservers Association (AWPA) 3. ASTM C 1177/1177M, C 1278/C 1278M, C SUBMITTALS (Refer Section ) A. Product Data: (For each type of process and factory-fabricated product) Indicate component materials and dimensions and include construction and application details. 1.4 QUALITY ASSURANCE (Refer Section ) A. Fire-Test-Response Characteristics: For assemblies with fire-resistance ratings, provide materials and construction identical to those of assemblies tested for fire resistance per ASTM E 119 by a testing and inspecting agency acceptable to authorities having jurisdiction and in accordance with UL s Fire Resistance Directory or GA-600, Fire Resistance Design Manual. 1.5 DELIVERY, STORAGE, HANDLING A. Stack plywood and gypsum products flat with spacers between each bundle to provide air circulation around stacks and under coverings. B. Protect against damage from weather, direct sunlight, surface contamination, construction traffic. C. Prevent from sagging. Protect edges, ends, and surfaces from damage. SHEATHING

2 PART 2 PRODUCTS 2.1 COMPLIANCE A. All manufacturers listed herein without a designated product must comply with the requirements of the specification, and, additionally, with the requirements of a specific manufacturer s product if indicated. Products of other manufacturers will be considered for acceptance provided they equal or exceed the material requirements and functional qualities of the specification. Furnish the Substitution Request Form with complete technical data for evaluation for Architect s approval. Additional approved manufacturers will be issued by Addendum. Refer to Division WOOD ROOF SHEATHING A. Plywood: DOC PS1 or 2, APA RATED, Exterior Structural I, Exposure 1, minimum 1-1/8 or 5/8" thick, unless otherwise noted with span rating not less than 48 or 24 oc. Applied over metal decking prior to installation of metal roofing. B. Plywood Treatments: 1. Preservative Treatment by Pressure Process: AWPA U1. Use Category UC2 for interior construction not in contact with the ground. Use Category UC3b for exterior construction not in contact with the ground. Use Category UC4a for items in contact with the ground. a. Preservative Chemicals: Acceptable to authorities having jurisdiction and containing no arsenic or chromium. b. Use treatment that does not promote corrosion of metal fasteners. 2. Fire-Retardant-Treated Plywood by Pressure Process: Products with a flame spread index of 25 or less when tested according to ASTM E 84, and with no evidence of significant progressive combustion when the test is extended an additional 20 minutes, and with the flame front not extending more than 10.5 feet beyond the centerline of the burners at any time during the test. a. Exterior Type: Comply with requirements specified above for fire-retardant-treated plywood by pressure process after being subjected to accelerated weathering according to ASTM D2898. Use for exterior locations and where indicated. b. Interior Type A: Use where exterior type is not indicated. c. Comply with performance requirements in AWPA C27. Provide a flame spread rating of less than 25 with no evidence of significant progressive combustion when tested for 30 minutes duration according to ASTM E-84. Impregnate fire retardant treatment into plywood manufactured under PS 1-83 or the performance standard of the American Plywood Association (APA) PRP-108. Bond panels with adhesives qualified for exterior exposure. d. Use treatment that does not promote corrosion of metal fasteners. 3. Kiln-dry material after treatment (KDAT) to maximum moisture content of 15 percent. Do not use material that is warped or does not comply with requirements for untreated material. 2.3 INSULATED WALL SHEATHING A. Fiberglass-Mat-Faced Sheathing: ASTM C 1177 and C1396, 5/8" thick, type X, 4' wide x 8', 9', or 10' long, coated fiberglass mats both faces, moisture-resistant gypsum core. Provide 5-yr warranty for manufacturing defects and 6-month warranty for exposure. 1. Silicone water-resistant treated silica and gypsum core, fiberglass mat facings on both sides, alkaliresistant coating. 2. Long Edges: Wrapped with water-repellant glass mat 3. Overall thickness: 5/8 inch 4. Classification: Type X, when tested in accordance with ASTM E 119 SHEATHING

3 5. Properties: a. Racking Strength, Ultimate: 711 lbs/lin ft. when tested in accordance with ASTM E 72 b. Flexural Strength, Parallel: 90 lbs, when tested in accordance with ASTM C 473 c. Humidified Deflection: less than 1/8 inch when tested in accordance with ASTM C 473 d. Nail pull resistance: 90 lbs, when tested in accordance with ASTM C 473 e. Water Absorption: less than 10 percent when tested in accordance with ASTM C 473 f. Surface Water Absorption: < 1 percent when tested in accordance with ASTM C 473 g. Permeance: >10 perms, when tested in accordance with ASTM E 96 h. Combustibility: Noncombustible when tested in accordance with ASTM E 136 i. Flame Spread/Smoke Developed: 5/0 when tested in accordance with ASTM E 84 j. Mold/Mildew Resistance: 10 when tested in accordance with ASTM D Manufacturers: a. Georgia Pacific "Dens-Glass Gold". b. BPB. c. National Gypsum. d. U.S.Gypsum. B. Sheathing Joint Sealants: Silicone emulsion sealant complying with ASTM C 920, Type S, Grade NS, compatible with sheathing tape and sheathing, approved by sheathing manufacturer for use with glassfiber mesh sheathing tape or covering exposed fasteners. C. Sheathing Tape: Self-adhering glass-fiber tape, minimum 2 wide, 10 by 10, or 10 by 20, threads/inch, of type recommended by sheathing and tape manufacturers for use with silicone emulsion sealant to seal joints in glass-mat gypsum sheathing. 2.4 FASTENERS A. Finish: Hot-dip galvanized or stainless steel where exposed to weather, in ground contact, in contact with treated wood, or in area of high relative humidity. B. Screws for Fastening Wood Panels to Metal Framing: ASTM C 954, except with wafer heads and reamer wings, length as recommended by screw manufacturer for material being fastened. For wall and roof sheathing panels, provide screws with organic-polymer or other corrosion-protective coating having a salt-spray resistance of more than 800 hours according to ASTM B 117. C. Screws for Fastening Gypsum Sheathing to Metal Framing: Steel drill-screws, in length recommended by sheathing manufacturer for thickness of sheathing board to be attached, with organicpolymer or other corrosion-protective coating having a salt-spray resistance of more than 800 hours according to ASTM B For steel framing less than inch thick, attach sheathing to comply with ASTM C For steel framing from to inch thick, attach sheathing to comply with ASTM C BUILDING WRAP A. Description: 6-mil thick, coated, cross-woven or cross laminated polypropylene fabric, or non-woven, spun-bonded olefin, UV stabilized, 2.7 oz/sy, NFPA 701, Class A B. Properties: 1. Tensile Strength: 45lbf/in. per ASTM D Perm Rating: perms when tested according to ASTM E 96, Method B. SHEATHING

4 C. Accessories: 1. House-Wrap Tape: Pressure-sensitive plastic tape recommended by house-wrap manufacturer for sealing joints and penetrations in building wrap. 2. Window Sealing Tape: Self-adhering modified rubberized asphalt, peel-and-stick feature for application around window and door perimeters. D. Manufacturers: 1. Raven Industries Dura Skrim 2FR. 2. DuPont. 3. Simplex. 4. Amoco. PART 3 EXECUTION 3.1 GENERAL REQUIREMENTS A. Do not use materials with defects that impair quality of sheathing or pieces that are too small to use with minimum number of joints or optimum joint arrangement. B. Cut panels at penetrations, edges, and other obstructions of work. Fit tightly against abutting construction, unless otherwise indicated. C. Securely attach to substrate by fastening as indicated, complying with the following: 1. NES NER-272 for power-driven fasteners. 2. Table , "Fastening Schedule," in ICC's "International Building Code." D. Do not bridge building expansion joints. Cut and space edges of panels to match spacing of structural support elements. E. Coordinate sheathing installation with installation of materials installed over sheathing so sheathing is not exposed to precipitation or left exposed at end of the workday when rain is forecast. 3.2 INSULATED SHEATHING INSTALLATION A. After installation of suitable corner bracing, install sheathing vertically with long joints in contact with framing. Apply full height or provide intermediate horizontal framing so that all edges are completely supported. Cover all framing. B. Apply to galvanized steel studs with 3/8" dia. corrosion-resistant pan head screws, length to accommodate 3/8" penetration thru steel face. Course to accommodate the wall reinforcement. Where noted, apply joint sealant to all joints to achieve a continuous weathertight and watertight surface. C. Attach insulation boards to metal studs, 8" o/c at perimeter and 12" o/c in field. 3.3 PLYWOOD SHEATHING INSTALLATION A. General: (as applicable) 1. Comply with applicable recommendations in APA Form No. E30K, "APA Design/Construction Guide for types of structural-use panels and applications indicated, including "Code Plus" installation provisions. SHEATHING

5 2. Place Sheathing with long dimension parallel to studs and continuously over at least two supports. 3. Provide solid blocking at all end joints. 4. Allow 1/8 spacing at all edges and joints. 5. Cover sheathing with building wrap per manufacturer's written instructions. Extend into jambs of openings and seal corners with tape. Seal seams, edges, fasteners, and penetrations with tape. B. Fastening to Metal Framing: Screw attach to cold-formed metal framing. C. Roof Sheathing Installation: 1. Attachment to Metal Decking: Space panels 1/8 inch apart at edges and ends. When used on roof under metal roofing, as detailed, attach plywood roof sheathing with mechanical screws and plates, in accordance with Factory Mutual Wind Resistance Classification I-90. Attach fasteners to metal deck penetrating top flutes only and exposed 3/4-inch minimum to 1-inch maximum. 3.4 JOINT AND PENETRATION TREATMENT A. Seal sheathing joints according to sheathing manufacturer's written instructions. 1. Apply glass-fiber sheathing tape to glass-mat gypsum sheathing board joints, and apply and trowel silicone emulsion sealant to embed entire face of tape in sealant. Apply sealant to exposed fasteners with a trowel so fasteners are completely covered. Seal other penetrations and openings. 2. Apply sheathing tape to joints between foam-plastic sheathing panels and at items penetrating sheathing. Apply at upstanding flashing to overlap both flashing and sheathing. 3.5 BUILDING WRAP INSTALLATION A. General: Comply with manufacturer's written instructions. Cover sheathing with weather-resistant building wrap as follows: 1. Cut back barrier 1/2 inch on each side of the break in supporting members at expansion- or control-joint locations. 2. Apply wrap to cover vertical flashing with a minimum 4-inch overlap, unless otherwise indicated. 3. Seal seams, edges, fasteners, and penetrations with tape. END OF SECTION SHEATHING