Part 1 - General

1.1 RELATED DOCUMENTS

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. This Section includes the following:

1. Embedded glass-mat gypsum sheathing board.

2. Sheathing joint-and-penetration treatment.

1.3 DEFINITIONS

A. Gypsum Board Construction Terminology Standard: Refer to ASTM C 11 for definitions of terms for gypsum sheathing board construction not defined in this Section or in other referenced standards.

1.4 SUBMITTALS

A. Submit in accordance with Section 01330.

B. Product Data: For each type of product indicated.

C. Informational Submittals: Submit manufacturer's instructions, special procedures, and perimeter conditions requiring special attention.

1.5 QUALITY ASSURANCE

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 (UL 263, CAN/ULC-S101) by a testing and inspecting agency acceptable to authorities having jurisdiction.

1. Fire-Resistance Ratings: Indicated by design designations from UL's "Fire Resistance Directory" and "Products Certified for Canada."

B. Single Source Responsibility: Except where specified otherwise, obtain gypsum board products, joint treatment, and accessories from single manufacturer or from manufacturers recommended by prime manufacturer of gypsum board products.

1.6 DELIVERY, STORAGE, AND HANDLING

A. Store materials protected against damage from weather, direct sunlight, surface contamination, construction traffic, or other causes. Stack GlasRoc^® Sheathing flat on leveled supports off the ground, under cover, and fully protected from weather.

1. Store and support GlasRoc^® Sheathing board in flat stacks to prevent sagging.

2. Protect materials to keep them dry.

3. Protect gypsum board panels to prevent damage to edges, ends, and surfaces.

1.7 COORDINATION

A. GlasRoc^® Sheathing:

1. Sheathing Board: Do not leave exposed to weather for more than 6 months.

1.8 WARRANTY

A. Manufacturer's standard warranty for product exposed to weather without failure, when installed in accordance with manufacturer's requirements, for period of not less than 6 months.

Part 2 - Products

2.1 GYPSUM SHEATHING

A. GlasRoc^® Sheathing: Meets requirements of ASTM C 1177.

1. Acceptable Product: Subject to compliance with requirements, provide the following:

a. "GlasRoc^® Sheathing" by CertainTeed Gypsum, Inc., Valley Forge, PA.

b. Substitutions: Submit in accordance with Section 01600.

2. Type and Thickness: Type X, 5/8 inch (15.9 mm) thick where indicated and as otherwise required to meet fire rating for specific element. [1/2 inch (12.7 mm) elsewhere.]

a. Flame spread: ASTM E 84 (CAN/ULC-S102): 0 maximum.

b. Smoke developed: ASTM E 84 (CAN/ULC-S102): 0 maximum.

3. Size: 48 by not less than 96 inches (1219 by not less than 2438 mm); longer lengths as available to reduce number of joints.

2.2 SHEATHING JOINT-AND-PENETRATION TREATMENT MATERIALS

A. Silicone Sealant: Meeting ASTM C 920, Type S, Grade NS, compatible with sheathing tape and sheathing, recommended by tape and sheathing manufacturers for use with glass-fiber mesh sheathing tape and for covering exposed fasteners.

B. Glass-Fiber Mesh Sheathing Tape: Self-adhering glass-fiber tape, minimum 2 inches (50 mm) wide, 10 by 10 or 10 by 20 threads/inch (390 by 390 or 390 by 780 threads/m), of type recommended by sheathing and tape manufacturers for use with silicone emulsion sealant in sealing joints in glass-mat gypsum sheathing board and with a history of successful in-service use.

2.3 ACCESSORY MATERIALS

A. Fasteners: Steel drill screws, in length recommended by sheathing manufacturer for thickness of sheathing board to be attached, with organic-polymer or other corrosion-protective coating having a saltspray resistance of more than 800 hours according to ASTM B 117.

1. For steel framing less than 0.0329 inch (0.835 mm) thick, attach sheathing with steel drill screws complying with ASTM C 1002.

2. For steel framing from 0.033 to 0.112 inch (0.84 to 2.84 mm) thick, attach sheathing with drill screws complying with ASTM C 954.

3. For wood framing, attach with nails or screws of type and spacing as recommended by sheathing manufacturer.

Part 3 - Execution

3.1 GYPSUM SHEATHING INSTALLATION

A. Comply with GA-253, ASTM C 1280 and manufacturer's written instructions.

B. Install GlasRoc^® Sheathing with acrylic coated side (logo side) out. Boards are also printed with "Install Other Side Out" on the backside.

C. Cut boards at penetrations, edges, and other obstructions of work; fit tightly against abutting construction, unless otherwise indicated.

1. Install boards with a 3/8-inch (10 mm) setback where non-load-bearing construction abuts structural elements.

2. Install boards with a 1/4-inch (6 mm) setback where they abut masonry or similar materials that might retain moisture, to prevent wicking.

3. Allow no joints greater than 1/8 inch (3 mm)

D. Coordinate sheathing installation with flashing and joint-sealant installation so these materials are installed in sequence and manner that prevents exterior moisture from passing through completed exterior wall assembly.

E. Apply fasteners so screw heads bear tightly against face of sheathing boards but do not cut into facing.

F. Do not bridge building expansion joints with sheathing; cut and space edges to match spacing of structural support elements.

G. Horizontal Installation: Install sheathing with long edges in contact with edges of adjacent boards without forcing. Abut ends of boards over centers of stud flanges, and stagger end joints of adjacent boards not less than one stud spacing. Screw-attach boards at perimeter and within field of board to each steel stud.

1. Space fasteners approximately 8 inches (200 mm) o.c. (or tighter spacing if recommended by manufacturer for specific application) and set back a minimum of 3/8 inch (10 mm) from edges and ends of boards.

3.2 SHEATHING JOINT-AND-PENETRATION TREATMENT

A. Seal sheathing joints according to sheathing manufacturer's written recommendations.

1. Short Term (6 month exposure) - Apply elastomeric sealant on joints and trowel flat. Apply sufficient quantity of sealant to completely cover joints after troweling. Seal other penetrations and openings.

2. Long Term (as an alternate to separate weather-resistive barrier) - Apply glass-fiber mesh sheathing tape to fiberglass reinforced gypsum sheathing board joints, and apply and trowel silicone emulsion sealant to embed sealant in entire face of tape.

3. Apply sealant to exposed fasteners with a trowel so fasteners are completely covered. Seal other penetrations and openings.

B. Water-Resistive Barrier

1. Consult building code authority having jurisdiction for requirements regarding water-resistive barrier installation, if necessary.

3.3 CEILINGS AND SOFFITS

A.  Finishing is accomplished with one of the following methods:

1. Direct-Applied Exterior Finish System (DEFS) is applied per the manufacturer’s specifications.

2. Apply 2”x10x10 glass mesh drywall tape and setting-type joint compound on the board joints. Skim coat the entire surface with a setting-type compound, prime and paint with good quality exterior grade primer and paint per the manufacturer’s recommendations.

CAUTION: This product contains continuous filament fiberglass. Fibers may be released in the normal handling of this product which can cause respiratory, minor skin and eye irritations. Avoid  contact with eyes and skin.

Do not breathe dust. Signs and symptoms of over-exposure include temporary irritation of eyes, nose, throat and lungs.  Aggravated medical conditions may include respiratory illness, however there are first aid procedures that can reduce risk of illness. These include moving to area for fresh air in the case of inhalation. If material irritates the eye, flush with running water for 15 minutes. When contact with skin occurs, wash gently with soap and water. However, when used under normal circumstances, following installation instructions, this product is not expected to present health hazards. For more information, consult the GlasRoc^® Material Safety Data Sheet by contacting CertainTeed at 800-233-8990.