How to Install Owens Corning Roll Roofing

Install roofing grade plywood or OSB sheathing, to provide the correct solid roof deck for Owens Corning roll roofing. To flatten it out for easy installation, pile the roll roofing, cut into 18-foot lengths, on a flat surface and acclimatize in at least a 50-degree Fahrenheit weather in order make it easier to work with. Cover the roof deck with 15-lb. roofing felt in courses parallel to the eave, with a 2-inch overlap between courses. It is recommended that you try to work with roll roofing in temperatures above 50 degrees Fahrenheit, or that you warm the material to at least that temperature before applying so that it lays flat without wrinkling or cracking. The warmer the temperatures, the easier it is to work with this type of roofing material.

Using a measuring tape, measure the roof's eave and rake edges to determine the roll roofing lengths you need for your starting strip that provides the means to install a "selvage" or double layer of roofing around the roof perimeter. Score and cut 9-inch wide lengths using a utility knife on the back of the fiberglass roofing. Overlap your rake and eave edges by 1/4 to 3/8 of an inch and fasten the selvage starting strip at 4-inch intervals, one inch in from each edge of the strip, as recommended by Owens Corning.

Align your first 36-inch wide roll-roofing length with the starting-strip overlap and run the lengths parallel with the eave. Fasten the top edge at 4-inch intervals and one inch in from the edge using 12-gauge galvanized roofing nails and a hammer. Apply asphalt-plastic lap cement over the selvage starting strip and push the fiberglass roofing length into the cement.

Overlap the top edge of the previously installed roofing length by a minimum of two inches. Fasten the next length with roofing nails in the same way as you did in Step 3. Apply asphalt-plastic cement under the lap, onto the installed lower roofing layer and bed the top roofing layer into the cement.

Continue to install the mineral-surfaced roofing up the roof in parallel lengths with at least a 2-inch overlap between each course. Overlap the side edges of end pieces by six inches and fasten nails at 4-inch intervals, 1 inch and 5 inches in from the edge, on the lower roofing layer. Apply lap cement under the side lap on the lower roofing layer and push the top layer into the cement.

Make ridge caps using 36-by-12-inch pieces of roll roofing, as recommended by Owens Corning. Apply lap cement 5 1/2 inches to each side of the ridge line using a chalk line as a guide. Shape each ridge cap by hand by slowly bending the roofing piece so that you have 6 inches to each side of the ridge line.

Bed the first ridge cap into the cement at the edge of the ridge line that faces into the prevailing wind. Fasten the cap with a nail to each side of the ridge line, 5 1/2 inches in from the opposing starting edge. Apply lap cement from the opposing starting edge to cover 6 inches of the cap, including the nail heads.

Position the next ridge cap over the cement to create an overlap. Fasten the ridge cap using the same method as you did in Step 7. Continue installing ridge caps using a 6-inch overlap for each cap along the ridge line. Use the same procedure for hip joints and work up from the lowest roof point so that the laps face down the roof.