Owens Corning

Owens Corning® ProArmor® Synthetic Roof Underlayment should be applied to a properly prepared dry deck that is smooth, clean and free from any depressions, projections or protruding nails. Acceptable roof deck materials for application are minimum 3/8 inch plywood or minimum 7/16 inch OSB. Roof decks should be structurally sound and meet or exceed minimum requirements of the roof deck manufacturer and local building codes. ProArmor® Underlayment is designed for use under metal and asphalt shingle roofing and must be covered within 90 days of application. Always follow safe roofing practices and OSHA safety requirements. Always wear and use fall protection devices when working on roofs. Use caution when walking or standing on ProArmor® Underlayment in wet or dusty conditions that may reduce traction. Failure to use proper safety equipment and footwear can result in serious injury.

Fasteners

If the roof will not be covered with approved roof covering on the same day, ProArmor® Underlayment must be attached to the roof deck using plastic or steel cap fasteners having a minimum 1 inch diameter cap. Provided there is no rain or high winds, ProArmor® Underlayment can be anchored with staples, cap staples or corrosive resistant 3/8 inch head x 1 inch leg roofing nails (ring shank preferred, smooth leg acceptable), when covered with primary roofing on the same day. All fasteners should be driven straight and flush with the surface. Consult local building codes for fastener type and spacing requirements.

Lap Requirements - All Slopes

If two or more pieces are required to continue a course, lap the ends at least 4 inches (must be at least 12 inches for slopes 2:12 to less than 4:12). End laps in a succeeding course should be located at least 6 feet from laps in the preceding course. Lap ProArmor® Underlayment a minimum of 6 inches from both sides over all hips, ridges and valleys. Where the roof meets a wall, extend ProArmor® Underlayment a minimum 4 inches up the wall.

Slopes 4:12 or Greater

Always lay ProArmor® Underlayment parallel to the eaves, lapping each course at least 3 inches over the underlying course. For same day coverage, minimum fastening locations for roofing nails, pneumatic nail guns or cap nails are shown in Fig. 1 and staples in Fig. 2. If required, additional fasteners can be used for same day coverage. See Fasteners section for additional details. If ProArmor® Underlayment will not be covered on the same day with metal or asphalt shingle roofing (extended exposure up to 90 days), use only plastic or steel cap fasteners having a minimum 1 inch diameter cap for all slopes. Fasten in both the overlapping area and the field area of ProArmor® Underlayment. Additional fasteners may be required in high-wind regions per local building codes. See Fig. 3 and Fasteners section for details.

Fig. 1-3

Slopes 2:12 to less than 4:12

On all lower slope applications, cover the deck with two layers of ProArmor® Underlayment. Roofing nails, pneumatic nail guns and staples may be used for same day installations. If ProArmor® Underlayment will not be covered on the same day with metal or asphalt shingle roofing (extended exposure up to 90 days), use only plastic or steel cap fasteners having a minimum 1 inch diameter cap. Begin by fastening a 21 inch wide strip of ProArmor® Underlayment along the eaves with the minimal fasteners needed to hold the course in place. Place a full-width sheet over the 21 inch course with the long edge placed along the eaves and completely overlapping the initial starter course. All succeeding courses will be a minimum of 42 inches wide and should be positioned to overlap the preceding course by 22 inches (to lowest solid centerline). Additional fasteners may be required in high-wind regions per local building codes. See Fig. 4 and Fasteners section for details.

Fig. 4

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