Some roof areas may not be suitable for shingles, especially due to low slope less than 212 down to 112. In these areas, the recommended product is Roof-Fast, a self-adhered membrane or SAM system, ideal for low-sloped roofing that combines a polymer chemistry of commercial grade modified bitumen membranes with the self-adhesive characteristics of an ice and water protector and the beauty of a granule surface.
The Roof-Fast System is comprised of Roof-Fast Cap, which is a fiberglass-reinforced self-adhesive cap sheet in a variety of attractive mineral surface colors with a released film on the backside.
Roof-Fast Base MA is a fiberglass reinforced nailable base with a special film surface designed for use with self-adhered cap sheet.
Roof-Fast 95, a self-adhering base sheet, is an alternative base sheet that may be used as part of the system.
To begin applying the Roof-Fast System using the Roof-Fast Base MA, start at the lowest edge of the roof. Prepare a starter strip by cutting the base sheet lengthwise in half and lay flat on the clean dry deck. Leave a minimum of 2 inches of base sheet overhanging the roof edge to cover any exposed joints in the wood fascia where water could penetrate. Fasten the Roof-Fast Base MA at 18 inches on center in a road down the approximate center of the starter sheet, leaving the upper edge free of fasteners for later steps in installation. The preferred nail of choice for this application is a one-inch diameter steel cap nail. Layout a full width base sheet overlapping the starter sheet by a minimum of 3 inches. Fasten through the overlap with one inch disc nails 9 inches on Center, working from the center of the sheet outwards. Ensure the sheet lays flat and wrinkle-free at all times. Fasten the center of the sheet with two rows of nails 18 inches apart in a staggered formation starting from the center and working outwards. Repeat this step until the entire surface has been covered.
Prior to beginning the drip edge installation, prime the surface of the drip edge metal flashing with primer for the self-adhering membrane and allow it to dry. Turn down the 2-inch overlap from the starter strip along the drip edge area and secure with roofing else at 9 inches on center to fascia. Cut a strip of Roof-Fast Cap 12 inches wide and lay it across the roof edge granular side down. Using the drip edge metal flashing as a guide, score the release film the width of the drip edge with the back of a utility knife. Remove the scored release film closest to the roof edge and place the primed drip edge metal flashing over the scored area of Roof-Fast. Fasten with roofing nails at 9 inches on center staggered approximately 1 inch in from the inside metal edge. To complete base sheet installation, secure the base sheet at the remaining perimeters with 1-inch steel cap nails 9 inches on center.
To apply the cap sheet, start at the lowest point of the roof and roll out the full-width Roof-Fast Cup sheet. Cut to the desired length, dry fit to the roof edge in a final position and allow to relax. Make sure that a three-and-a-half-inch side lap on the Roof-Fast Cap is opposite, furthest away, from the drip edge metal flashing. Using the butterfly technique while kneeling on the upper half of the position cap sheet, fold back half of the width towards you to expose the release film. Remove the remaining release film from 12 inches of the inverted cap sheet strip. Remove the exposed release film from the roof fast cap half-width and slowly walk the cap sheet into place over the base sheet. Fold down the upper unadhered cap sheet. Remove the release film and gently place into final position. Use a roller to ensure consistent contact of the Roof-Fast Cap to the base sheet. In hot weather it may be best to limit the length of the individual pieces of brew fast to a maximum of 12 feet for ease of handling. Roll out the second cap sheet cut to size dry fit into final position and allow to relax. Ensure the second sheet overlaps the three-and-a-half-inch side lap of the first sheet. Repeat the procedure for installation of the first sheet, remembering to remove the release film covering the side lap on the first sheet. Continue up the roof, repeating this procedure until all surface is covered.
To apply an end lap to the Roof-Fast Cap sheet, cut a section of cap sheet that overlaps the adhered section by 6 inches. Apply a 6-inch bead of mastic sealant with a trowel on the overlap section. Peel off the release film and press firmly. Remove the remaining release film on the back of the cap sheet and firmly press onto the base sheet. Use a roller to ensure consistent contact of the Roof-Fast Cap to the base sheet. For the alternate base application, using the Roof-Fast 95 base apply a coat of self-adhering primer to the full deck and allow to dry. Cut the sheet to size and using the butterfly technique while kneeling on the upper half of the position base cap sheet, fold back half of the width towards you, remove the release film, and slowly walk the base sheet into place. Fold down the upper unadhered cap sheet, remove the release film, and gently place into position. As an optional application, where roof area and roof slope allow, instead of starting with a half-width of Roof-Fast Base MA, use a full width of IKO’s GoldShield premium ice and water membrane. In this installation at the eaves and rakes, the drip edge is installed over the GoldShield and below the fastened base sheet layer. The drip edge should be set in continuous bands of asphalt cement to ensure water tightness with the membrane layers.