How to Install Asphalt Mineral Roofing on Flat Roofs
- 1). Install a solid roof deck of either roofing grade plywood or OSB sheathing. Asphalt mineral roofing requires a solid roof deck for correct installation. Use a push-broom and sweep the roof deck clear of dirt, leaves and debris. Scrub any grease and oil marks off the deck with a damp cloth and detergent.
- 2). Allow the roof deck to completely dry out before beginning the asphalt mineral roofing installation. Use a measuring tape and measure across the roof from side to side to determine the cut lengths of the roofing roll. If the flat roof has any slope, measure across the roof perpendicular to the slope. Use a measuring tape and measure between the edges of the other two sides of the roof to determine the quantity of cut lengths you need.
- 3). Unroll the selvage lap asphalt mineral roofing and transfer the length measurement onto it using a measuring tape. Add one inch to the measurement to allow for a 1/2-inch overhang on each roof edge. Mark a line across the width of the felt at the measurement point with a marker pen and a straight edge.
- 4). Cut along the line using a utility knife and use a straight edge as a guide. Roll out the next length and cut that as you did before. Continue to cut all the lengths you need and stack them together so that the material relaxes and straightens out.
- 5). Use a utility knife, and cut one of the lengths in half width-wise along the dividing line between the mineral coating and the smooth half of the felt. Roll on roofing tar with a paint roller from the starting edge of the roof along its length to each side and to the width of the smooth piece of felt you cut.
- 6). Position the smooth piece of felt over the tar and to the starting edge and side edges of the roof. Using roofing nails and a hammer, fasten the felt in place at 12-inch intervals along the top and bottom edges and at three equal intervals along the side edges.
- 7). Apply roofing tar over the installed felt and onto the roof deck, to 36-inches wide. Position the first length over the installed felt and overhang the roof edges by 1/2-inch. The mineral coating part goes face up over the installed felt, and the smooth half goes over the tar on the roof deck.
- 8). Fasten the length with roofing nails at 12-inch interval along the top edge of the smooth part of the felt. Fasten the edges at three equal intervals into the smooth part of the felt only. In this way you install a concealed fastening system. Apply roofing tar over the smooth felt on the previous length and on the roof deck, to 36-inches wide.
- 9). Position the next length over the smooth felt beneath and align the mineral coating edge up to the mineral coating edge of the one beneath. Fasten the felt in place using the same method as before. Continue to install lengths of asphalt mineral roofing one at a time using the same procedure until the roof is complete.
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