Mineral-surfaced roll roofings are made in various colors, both solid and blended. The mineral granules on the surface protect the asphalt coatings from the weather and increase the fire-resistant qualities of the roofings. Manufacturers’ directions should be followed with respect to storing, handling, and temperatures at which roll roofings should be laid.
Minor damages to mineral-surfaced roll roofings, such as nail holes or other small breaks, may be repaired by applying flashing cement.
To repair large breaks, the horizontal seam below the break should be opened, and a strip of roofing of the type originally used slipped under it, allowing the strip to extend at least 6 inches beyond the edges of the break. The lower edge should be flush with the horizontal exposed edge.
Lap cement should be applied liberally on the upper surface of the repair strip before inserting it. After the strip has been inserted, press the edges of the roofing down firmly and nail securely. Space the nails 2 inches apart about three-fourths inch from the edge of the break. Apply lap cement to the horizontal seam and renail it.
Where a considerable area has been damaged, remove the damaged area and replace it with new roofing of the same type, using full-width sheets lapped, cemented, and nailed.
Leaks at the seams of roll roofing are caused principally by inadequate nailing and cementing of the roofing, by loose nails, and by buckling of the roofing at the seams. To repair leaky seams, first sweep out the seams to remove accumulated dust and dirt, cut all buckles which terminate at the seams, and insert a strip of roofing in the same manner as for larger breaks.
Roll roofings may be applied over old wood shingles or other roofing materials, provided the surface of the old covering is in reasonably good condition and the surface has been made smooth in the same manner as for mineral-surfaced asphalt shingles. If not, the worn roofing should be removed and the roof deck prepared in the same manner as for the application of asphalt shingles. Manufacturer’s directions should be followed in applying the new roll roofing.