How To Install Roll Roofing

Roll roofing comes in a variety of colors. It's a heavyweight composition roofing material that can be used on low-pitch roofs- down to a 1 in 12 slope with the concealed-nail method. This makes it useful on roofs where nothing else will work.

Roll roofing can crack in cold weather, so don't apply it when it's below 45 degrees F. To finish a job after the weather turns colsd store the rolls in a warm area prior to application.

Exposed- Nail Application

Apply roll roofing over a smooth deck, allowing a1/2 inch overhang along the eaves. Cut is flush with the rake edges and nail on a metal drip edge with galvanized roofing nails, 3/4 inch from the edge. Cover valleys with 18 inch-wide strips of roll roofing. Nail one side every 6 inches. Completely seat the strip in the valley and nail the other side.

Snap a chalk line across the roof 35.5 inches from the eaves to align the first course. Position the roll and nail it every 2 feet along the top. Put nails 3 inches apart at the rake and eave edges. If one sheet doesn't cover the roof, overlap the next piece by 6 inches. Nail the bottom section , apply roofing cement, then nail the ovelap in place.

Snap a chalk line 34 inches from the top edge of the first strip as a guide for the next one. Tack the upper edge of the seconf strip. Then spread a 2-inch-wide layer of roofing cement along the upper edge of the first strip and nail the seconf course over it.

If succeeding courser must be end-lapped, stagger the joints so that they are not directly above each other.


Cut the roofing to meet (but not overlap) at hips and ridges. Snap a chalk line on each side, 5.5 inches from the center of the hip or ridge. Spread a 2 inch wide layer of roofing cement from each line toward the center. Cut a 12 inch wide strip of roofing to the length of the hip or ridge, gently bend it in the center to fit over the joint and nail it down.

Concealed-Nail Application
Reroofing using the concealed-nail roofing method is similar to the exposed nail method. Roofing cement holds the roofing in place and makes it watertight with this method. Nails will not show when completed.

First, install valley flashing as described in the exposed nail application method. Next, cut 9 inch-wide strips and nail them along the rakes and eaves.
Snap a chalk line across the rood 35.5 inches from the eaves. Lay the first strip along it. Nail the top edge only. Lift the bottom and side edges and coat the starter strips with roofing cemet. Press the roofing down.

Lay the second course 4 inches down from the upper edge of the first strip. Nail it every 4 inches. Coat the overlap and rake starter with cement and press the strip into place.

Make any end-laps 6 inches wide. Coat the bottom layer with cement nail it down, then press the top strip into it. Cement the ride press the top strip into it. Cement the ridge strip into place and put weights (such as cinder blocks) on it to hold it in place until the roofing cement dries. Cover the rakes with metal drip edging, cemented down and nailed every 6 inches. Caulk over the nail heads.