Asphalt roof tiles, also known as shingles, are one of the easier types of roofing materials to install and weigh only about a third as much as concrete shingling. Select a clear, sunny day for your roofing project, and be prepared to spend at least fifteen hours of work on a small roof, and more if this is your first time doing such a project. You can cut the man-hours in half by having a friend help; she can lay asphalt shingles horizontally while you work on the diagonal, or you can work on opposite sides of the roof.
Prepare the roof for asphalt shingles by cleaning off any debris and nailing down any loose boards. Then nail the drip edge, also known as an edge iron, along the eaves and the sloping edge of the roof, also known as the rake.
Staple or nail aluminium flashing--lightweight sheet metal--around any protruding vents or chimneys. Flashing can also be used to cover any knotholes in the roof.
Apply tar paper or roof felt over the top of the drip edge and across the entire roof. Just square the roll up so that it overlaps the inside border of the drip edge by at least a couple of inches, remove the adhesive backing, and press it into place. Cut scraps of tar paper to cover over the edge of the flashing around vents and chimneys.
Nail the starter strip, a strip of asphalt that lines up with the edge of the roof, in place above the eaves.
Starting in the lowest corner of the roof, nail one shingle in place then work both across and up the roof, layering successive rows of shingles on top of those below.
Overlap shingles, following the manufacturer's instructions for how much exposed shingle there should be underneath each overlapping layer. In most cases, the exposure will be between five and six inches for asphalt shingles.
Seal around the flashing on any protrusions by applying roofing tar from a tar gun. You can also apply rubber and plastic flanges around the protrusions, but these will still need to be sealed with roofing tar to prevent water from seeping in.
Nail roof cap shingles, shaped like upside-down shallow "V"s, in place at the peak of the roof.
Make sure the asphalt shingles on the edge of the roof overlap the board at the roof's edge by at least 1/8 inch. This makes water drip away from the roof boards instead of onto them. Pneumatic nailers or nail guns make the job go faster, but nailing by hand often yields better, more consistent quality. Offset your shingles--move them a little to the left or right--in each successive row so that the tabs and gaps in the shingles don't line up one over the other and let water through.
Always use great care when using a nail gun or even hammer or nails. Be conscious of where you're stepping while working on a roof; you don't want to fall over the edge.