Your home's rooftop is the first line of defense against moisture damage.
Shingles installed in an overlapping pattern work to protect the framework of your house by sheeting water off of the rooftop and down into the rain gutters. A properly installed shingle roof consists of a series of layers of different building materials, including sheathing, flashing, roofing felt, and, finally, the shingles themselves. Building a shingle roof does not require any specialized tools, generally, you will find everything you need to complete the job in your garage. You always want to be careful, though,when working on a rooftop because the potential always exists for falls and serious injury.
Instructions
Preparing the Rooftop for Shingling
1. Start by covering the rafter on the roof with panels of 7/16th-inch thick oriented strand board (OSB). Start at the top and lay these boards in a brick pattern, so that the seam between two panels falls on the halfway point of the panels above and below. Use your tape measure and pencil to mark the boards and a circular saw to cut the panels to size as needed. Mark any vent pipes and use a drill, and then a jig saw, to cut holes in the sheathing where these pipes extend through the house's framework. Nail the boards to the rafter with corrosion-resistant nails.
2. Apply flashing to your valleys, where the two sections of roof meet to form a low point. The valley flashing provides an important layer of water resistance along the vulnerable low point between roofing sections. Nail the flashing in place with roofing nails driven every 6 inches on either side of the folded metal. Seal the nail heads and along the sides of the flashing with roofing sealant.
3. Apply drip edge to the edges of the rooftop. This bent metal flashing is fastened to the roof and hangs over the edge onto the fascia and rakes. Nail the wider side of the drip edge to the rooftop, and the smaller side to the roof edges. Fasten the drip edge with roofing nails driven every 6 inches, then seal the nail heads and the edges of the drip edge with roofing sealant.
4. Install all of your vent pipe flashing. These specialized pieces consist of a tubular piece of metal fitted to a wide sheet metal flange. The tube slides over the vent pipes that extend from many of your house's appliances and plumbing fixtures. The point where the vent pipes break through the sheathing is particularly vulnerable to moisture leakage. The vent pipe flashing creates a seal over this vulnerable point.
5. Affix chimney flashing around the chimney. Chimney flashing consists of a series of sheet metal pieces that overlap to form two layers of protection over the extremely vulnerable chimney area. Chimney flashing is probably the trickiest part of the roofing installation. Make sure you follow the chimney flashing manufacturer's instructions regarding the proper installation of this specialized flashing material.
Applying Shingles to the Rooftop
6. Roll out a layer of roofing felt. Run this first layer along the base of the roof, starting from the edge and extending up. Staple the roofing felt here and there to keep it from blowing away while you work. You don't need to overdo it when tacking the felt; it will be held firmly in place once the shingles are installed over the top.
7. Start at the base of the house and work your way up. The first thing you want to do is cut and install the starter strip. Starter strip can be cut from your 3-tab asphalt shingle material. Use your utility knife to cut the shingles lengthwise just above the cut-out tabs, and then slice about 2 inches off the top of the shingle so you are left with a strip of asphalt shingling material. Cut enough starter strip to extend across the length of the section of rooftop with which you are starting.
8. Position the starter strip so the base lies flush with the edge of the roof. Nail the starter strip with roofing nails driven every 6 inches into the OSB sheathing.
9. Once you've got the starter strip extended along the entire base of the roof, then start fastening your first shingle course. Start at one side of the roof and position the shingle so the base is flush with the base of the starter strip. Nail the 3-tab asphalt shingle in place with four roofing nails; one driven above each tab, and the remaining two driven about 1 inch in from each shingle edge. Drive the nails about 1 inch above the cut-outs on the 3-tab shingle, so that they will be covered up by the next course of shingles.
10. Extend the shingles all the way across the roof. Use your utility knife to trim away excess material when you reach the far side of the rooftop.
11. Fasten your second shingle course. Stagger the cut-outs and position the second course of shingles so the base lies flush with the end of the cut-outs in the shingle course below. The second shingle course should be covering the nails holding the first course in place.
12. Continue this shingling pattern. When necessary, run another layer of roofing felt. Make sure to overlap one course of roofing felt with the course above it. The overlap between felt courses should be 1 or 2 inches.
13. Once you've applied shingles to a section of rooftop, repeat the process until the entire roof is covered with shingles.
14. Fasten your ridge caps along the roof's ridge lines. These specialized shingles are folded over so they cover the nail heads on the uppermost shingle course on each side of the roof. Snap a chalk line from one end of the roof's ridge to the other. Set the first ridge cap in place at one edge of the roof and fasten it with two roofing nails driven into each side of the roof's ridge. Make sure to drive the nails beyond the exposure line so that they will be covered by the next ridge cap in line. Refer to the ridge cap manufacturer's instructions regarding the proper exposure for the ridge caps. Extend the ridge caps from one end of the ridge to the other. The final ridge cap will possess the only two nails exposed once the roof is finished. Seal these exposed nails with roofing sealant.
