36E77619B0003-0003004.pdf

VA Green Homes - Project 550-316 Department of Veterans Affairs

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AIR AND MOISTURE BARRIER

INSULATION AND FLASHING

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SECTION 07 13 26

AIR AND MOISTURE BARRIER INSULATION AND FLASHING

PART 1 - GENERAL

1.01 DESCRIPTION

A. This Section includes the following:

1. Provide a thermal, water and air resistance barrier wall system for exterior cold-formed metal wall assemblies.

a Provide continuous exterior wall insulation.

b. Building-Wrap Tape: Pressure-sensitive plastic tape recommended by building-wrap manufacturer for sealing joints and penetrations in polystyrene board insulation.

c. Concealed rubberized-asphalt strip flashing.

D. Concealed rubberized-asphalt strip flashing under roofing.

1.02 RELATED WORK

A. Related Sections include the following:

1. Section 07 31 13, ASPHALT SHINGLES, for asphalt shingle roofing.

2. Section 07 46 43, FIBER-REINFORCED CEMENTITIOUS SIDING, for siding materials.

3. Section 07 60 00, FLASHING AND SHEET METAL, for metal and flexible flashing materials and installation.

4. Section 07 92 00, JOINT SEALANTS, for joint-sealant materials and installation.

1.03 SUBMITTALS

A. Product Data: Include manufacturer's written instructions for evaluating, preparing, and treating substrate, technical data, and tested physical and performance properties of air and moisture barrier.

B. Letter from the Contractor on the Contractor’s letterhead stating that all components of the air and moisture barrier system, including those specified in other Sections, are compatible with each other.

C. Written report from the air and moisture barrier manufacturer on inspections completed during installation.

1.04 QUALITY ASSURANCE

A. Installer Qualifications: A qualified installer who is acceptable to air and moisture barrier manufacturer to install manufacturer's products.

B. Source Limitations: Obtain air and moisture barrier materials, through one source from a single manufacturer, including materials specified in other sections such as sealants.

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1.5 SYSTEM DESCRIPTION

A. Furnish and install an exterior wall system that effectively controls thermal, air, vapor and water performance and provides continuity of the building envelope enclosure. The system shall include the follow-ing:

1. Insulated sheathing secure to the exterior of the metal wall framing assembly.

2. Joint, penetration and gap sealing material for sealing component joints, penetrations through the wall system and gaps between the building envelope enclosure components and wall opening frames.

B. Performance Characteristics:

1. Thermal performance:

a. Exterior insulation: ASTM C518, Stabilized R-value of 6.5 at one inch of thickness with a maximum six month exposure capability to outdoor elements and 15 year thermal warranty.

2. Air barrier performance: When tested in accordance with ASTM E2357, at a test pressure of not less than 6.24 psf, air infiltration shall not exceed 0.04 cfm per square foot (0.2L/*m2) of fixed wall area.

Testing should be conducted at positive and negative sustained wind loading of 12.5psf (600Pa) for one-hour duration in each direction, pressure cycling of the wall at 2000 cycles in both the positive and negative direction, ending with wind gust loading at 25psf.

3. Water penetration: when tested in accordance with ASTM E331, no un-controlled water penetration shall occur at a minimum differential pressure of 6.24 psf for minimum test duration of 2hrs.

4. Mold resistance: Wall system components shall provide non-food source for fungal growth.

C. Pre-Construction Meeting: Convene a meeting at the site and ensure the attendance of the Contractor, installer of air and moisture barrier systems, manufacturer of the air and moisture barrier systems including those specified in other Sections. The agenda shall include the review of all materials to be applied and the installation methods and precautions that are to be taken.

1.05 DELIVERY, STORAGE, AND HANDLING

A. Store rolls according to manufacturer's written instructions.

B. Protect stored materials from direct sunlight.

1.06 PROJECT CONDITIONS

A. Environmental Limitations: Apply air and moisture barriers within the range of ambient and substrate temperatures recommended by air and moisture barrier manufacturer. Do not apply air and moisture barriers to a damp or wet substrate.

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1. Do not apply air and moisture barrier in snow, rain, fog, or mist.

B. Maintain adequate ventilation during preparation and application of air and moisture barrier materials.

1.07 WARRANTY

A. Special Manufacturer's Warranty: Written warranty, signed by air and moisture barrier manufacturer agreeing to replace air and moisture barrier material that does not comply with requirements or that does not remain watertight during specified warranty period.

1. Warranty does not include failure of air and moisture barrier barrier due to failure of substrate prepared and treated according to requirements or formation of new joints and cracks in substrate exceeding 1/16 inch (1.6 mm) in width.

2. Warranty Period: Three years after date of Substantial Completion.

B. Special Installer's Warranty: Written air and moisture barrier Installer's warranty, signed by Installer, covering Work of this Section, for warranty period of two years.

PART 2 - PRODUCTS

2.1 INSULATION.

A. Continuous Exterior Insulation meeting the following physical proper-ties:

1. ASTM C1289 type 1, class 2.

2. Compressive Strength (ASTM D1621): 25 psi, minimum.

3. Aged thermal Resistance (ASTM C518, measured at Mean Temp of

75F): F- 6.5 at I inch of thickness with 15 year thermal warran-ty.

4. Flexural Strength (ASTM C203): Minimum 55 psi .

5. Water Absorption (ASTM C209 ): Minimum 0.1 percent by volume.

6. Water Vapor Permeance (ASTM E96): <0.03 perms.

7. Maximum Use Temperature: 250 degrees F.

8. Class A (<and/or= 25 Flame spread Index and <450 Smoke Developed

Index) classified at Max.thickness per UL 723 criteria or ASTM E84 criteria.

a. Panel Size: 4’-0” wide x 12’-0” long, square edge panels.

b. Thickness and Stabilized R-Value: Nominal 0.625 inch thick-ness, R-4.1 1.0 inch thickness,R-6.5.

2.02 RUBBERIZED-ASPHALT STRIP FLASHING

A. Rubberized-Asphalt Strips: 40-mil (1.02 mm) thick, self-adhering sheet consisting of 37-mil (0.95-mm) of rubberized asphalt laminated

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07 13 26 - 4 to a 3-mil (0.07 mm) thick, polyethylene film with release liner on adhesive side and formulated for application with primer or surface conditioner that complies with VOC limits of authorities having jurisdiction. Provide minimum 9-inch wide strips.

1. Physical Properties: As follows, measured per standard test methods referenced:

a. Tensile Strength: 250 psi (1.7 MPa) minimum; ASTM D 412, Die C, modified.

b. Ultimate Elongation: 200 percent minimum; ASTM D 412, Die C, modified.

c. Low-Temperature Flexibility: Unaffected at minus 45 deg F

(minus 43 deg C); ASTM D 1970.

d. Crack Cycling: Unaffected after 100 cycles of 1/8-inch (3-

mm) movement; ASTM C 836.

e. Vapor Permeance: 0.05 perms (2.9 ng/Pa x s x sq. m);

ASTM E 96, Water Method.

2.03 RUBBERIZED-ASPHALT STRIP ROOFING UNDERLAYMENT

A. Rubberized-Asphalt Strips: 40-mil (1.02 mm) thick, self-adhering sheet consisting of 37-mil (0.95 mm) of rubberized asphalt laminated to a 3-mil (0.07 mm) thick, polyethylene film with release liner on adhesive side and formulated for application with primer or surface conditioner that complies with VOC limits of authorities having jurisdiction. Provide minimum 9-inch wide strips.

1. Physical Properties: As follows, measured per standard test methods referenced:

a. Tensile Strength: 250 psi (1.7 MPa) minimum; ASTM D 412, Die C, modified.

b. Ultimate Elongation: 250 percent minimum; ASTM D 412, Die C, modified.

c. Low-Temperature Flexibility: Unaffected at minus 29 deg F

(minus 20 deg C); ASTM D 1970.

d. Crack Cycling: Unaffected after 100 cycles of 1/8-inch (3-

mm) movement; ASTM C 836.

e. Vapor Permeance: 0.05 perms (2.9 ng/Pa x s x sq. m);

ASTM E 96, Water Method.

2.04 AUXILIARY MATERIALS

A. General: Furnish auxiliary materials recommended by air and moisture barrier system manufacturer.

B. Sheet Strips: Self-adhering, rubberized-asphalt composite sheet strips.

C. Liquid Membrane: Elastomeric, two-component liquid, cold fluid applied, trowel grade or low viscosity.

D. Substrate Patching Membrane: Low-viscosity, two-component, asphalt-modified coating.

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E. Mastic, Adhesives, and Tape: Liquid mastic and adhesives, and adhesive tapes.

PART 3 - EXECUTION

3.01 EXAMINATION

A. Examine substrates, areas, and conditions, with Installer present, for compliance with requirements and other conditions affecting performance.

1. Proceed with installation only after unsatisfactory conditions have been corrected.

3.02 SURFACE PREPARATION

A. Clean, prepare, and treat substrates according to manufacturer's written instructions. Provide clean, dust-free, and dry substrates for air and moisture barrier application.

B. Prepare, fill, prime, and treat joints and cracks in substrates.

Remove dust and dirt from joints and cracks according to ASTM D 4258.

1. Install sheet strips and center over treated construction and contraction joints and cracks exceeding a width of 1/16 inch (1.6 mm).

C. Bridge and cover isolation joints, expansion joints, and discontinuous deck-to-wall and deck-to-deck joints with overlapping sheet strips.

1. Invert and loosely lay first sheet strip over center of joint.

Firmly adhere second sheet strip to first and overlap to substrate.

3.03 INSULATION INSTALLATION

A. Install insulation in accordance with manufacturer’s recommendations:

Fasten to exterior face of exterior metal stud wall framing using sheathing manufacturer’s recommended type and length screw fasteners with washers. Abut panels tightly together and around openings and penetrations.

1. Install sheathing panels horizontally. Use maximum lengths to minimize number of joints. Locate edge joints parallel to and on framing. Center end joints over supports and stagger in each course. Provide additional framing wherever panel joints do not bear against framing plate or sill members.

2. Fasten panels to each support with fasteners spaced 12 inches on center at perimeter of the wall and 16 inches on center in panel field. Set back perimeter fasteners 3/8” from edges and ends of panel units. Drive fasteners to bear tight and flush with surface of insulation. Do not overdrive fastener causing damage to the insulation board facer. Perimeter fasteners can be detailed to bridge the gap of abutting board joints due to the 2” diameter of the washer used to fasten the board to the studs. Maximum of two board joints may be bridged per fastener.

3. Install flashing at end and edge joints in accordance with sheathing manufacturer’s joint sealing recommendations.

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4. Install flashing behind wall tie and mechanical fastening assemblies for rain screen claddings according to manufacturer’s recommendations.

5. Seal sheathing joints and penetrations of sheathing in accordance with sheathing manufacturer’s joint and penetration sealing recommendations.

6. After base flashing, which may include a termination bar running horizontally along the top edge of the flashing, is installed on exterior of insulated sheathing.

3.04 RUBBERIZED-ASPHALT STRIP APPLICATION

A. Install self-adhering sheets according to air and moisture barrier manufacturer's written instructions and recommendations in

ASTM D 6135.

B. Application at Openings: Apply strips at sill first, then jambs, and lastly at head of openings. Install over fins and flanges, and install weatherproofing membranes for general wall areas over the strips.

C. Application at Roofs: Apply strips from low point to high point of roofs to ensure that side laps shed water and in accordance with roofing manufacturer’s recommendations.

D. Correct deficiencies in or remove sheet air and moisture barrier that does not comply with requirements, repair substrates, and repair sheet flashings.

3.05 QUALITY ASSURANCE DURING INSTALLATION

A. Manufacturer of air and moisture barrier materials shall inspect the installation on the first two full days of installation activities, at least one full day while the installation continues and at the completion of the installation. Provide a written report of the observations during inspections, and what actions were taken to correct deficiencies.

3.06 PROTECTION AND CLEANING

A. Protect air and moisture barrier from damage and wear during remainder of construction period.

B. Clean spillage and soiling from adjacent construction using cleaning agents and procedures recommended by manufacturer of affected construction.

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