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Product Name

Self-Adhesive Roofing Underlayment

Product Description

Self-adhesive roofing underlayment is used on steep sloped roofs beneath shingles, tiles, metal, copper shake, slate, synthetic roofing, and wood shake. Self-adhesive roofing underlayment is a waterproofing membrane designed to reduce the occurrence of leaks caused by ice damming and wind driven rain conditions penetrating primary roof system coverings, as well as damaged roof coverings, and as temporary cover on exposed roof systems. Self-adhesive underlayment is an advanced polymer formulation high temperature bituminous underlayment ideally suited for tile and metal roofing.

COMPOSITION & MATERIALS

Self-adhesive roofing underlayment, steep sloped roofing underlayment comprised of an advanced formula HT bituminous waterproofing membrane layer, a high strength PE and PP compound membrane, and a siliconized poly split release liner.

PRECAUTIONS & LIMITATIONS

• Depending on roof pitch and surface conditions (wet, dusty, frost, dew), coefficient of friction may change, and surface can become slippery.

• Consistent with good roofing practices as referenced by OSHA, use caution when walking or standing on roof deck, and always wear fall protection.

• In high wind or long term exposed roof conditions, follow installation instructions to increase fastening rate hold down force on the underlayment, and seal laps.

• Do not leave permanently exposed to sunlight. This product is not designed to replace primary roof covering.

Installation

FOR USE UNDER METAL, TILE, SLATE, WOOD SHAKE, COMPOSITION SHINGLES

Self adhesive roofing membrane is bonded to a properly prepared, dry (not damp), and clean substrate which is defined as, but is not limited too: free of dirt; dust; debris; oils; un-adhered coatings; protrusions; voids; any other contaminates that may result in a surface that is not sound or is un–even and affects the adhesion of the membrane to the substrate.

Acceptable substrates for self adhesive roofing membrane are plywood, OSB, wood plank or composition, concrete, masonry, faced gypsum and approved insulation. Other surfaces may be acceptable, but the installer is responsible to determine acceptable substrate surface and whether priming is required so that self adhesive roofing membrane will stay adhered to that substrate.

Self adhesive roofing membrane must be installed above properly ventilated space as it is considered a vapor barrier. Installation of self adhesive roofing membrane occurs when the release film is removed and the self–adhesive underside is matted onto the approved substrate using applied pressure. Self adhesive roofing membrane is manufactured with a 175px selvage edge on one side and only this side will be used on a lengthwise overlap when being installed.

For vertical laps, use a 15cm overlap, except in ice damming applications, use a 30cm overlap. Starting at the low point, and with salvage edge at the high point, position horizontally a full roll or cut the membrane into 3–5m lengths and re–roll loosely. Peel back 30–60cm of release film, align the membrane, and continue to peel the release film from the membrane. Press the membrane in place with heavy hand pressure. Apply uniform pressure to the membrane roll side and end laps to insure water tightness and bonding to the substrate.

Always work from the low to the high point of the roof. Follow good roofing practice by orientating self adhesive roofing membrane so side laps shed water. Apply the membrane in valleys before the membrane is applied to the eaves. For valley and ridge application, peel the release film; center the sheet over the valley or ridge, drape, and press into in place. Work the center of the valley or ridge outward in each direction. Following placement along the eaves, continue application of the membrane up slope. If nailing of the membrane is necessary on steep slopes, especially during hot or cold weather, back nail and cover the nails by overlapping with the next sheet.

Winter climates can produce ice dams and snow loads against exterior siding while wind driven rains can create headwater heights that challenge the water tightness of exhaust vents, skylights and exterior wall siding. Extend self adhesive roofing membrane to the height as recommended by the local building code or to the highest locally expected level in order to maintain water tightness from wind driven rain, headwater back–up, ice dams and snow load.

Release liners are slippery. Remove from work area immediately after membrane application. Do not fold over the roof edge unless the edge is protected by a drip edge, gutter, or other flashing material. Do not install on the chamfered edges of wood plank. Do not install directly on old roof coverings. Do not install directly under roof coverings especially sensitive to corrosion,

such as zinc, without providing proper ventilation. Repair holes, fish mouths, tears, and damage with a round patch of membrane extending past the damaged area 15cm in all directions. If fasteners are removed leaving holes in the membrane, they must be patched. The membrane may not self–seal open fastener penetrations. Do not install fasteners through the membrane over unsupported membrane areas of the structural deck, such as over the joints between adjacent structural panels. Self adhesive roofing membrane has a minimal application temperature of 5°C. The membrane, deck surface, and the air shall be at a temperature of 5°C or greater during installation.

Self adhesive roofing underlayment is not designed to replace the primary roof covering material, or for indefinite outdoor exposure. The finished roof must completely cover the membrane.