Roof replacement requires no special skills and can be done by anyone with the proper tools, materials, and guidance. Roofing materials are designed to last an average of 40 years. All roofs will eventually become worn and weathered and will need to be repaired in part or replaced completely.
There are several types of roofing material including wood, asphalt, slate, and metal. This article will focus on the installation of asphalt roof shingles.
Step 1 - Work Safely
Working on a pitched roof might take a little getting used to. All that is required to maintain secure footing is 2x4 lumber that is 4 or 5 feet in length. Lay a 2x4 board flat and horizontal onto the roof a few feet below where you’ll be working.
Drive a #16 nail through each end of the 2x4, through the shingles and most importantly, into the edge of a rafter. Use the 2x4 as a cleat to keep you from sliding down the roof. Pull it up and re-nail it in place as you work your way up and across the roof.
Step 2 - Remove Worn and Damaged Shingles
Using your hammer claw and a utility knife, remove all damaged or worn shingles, all the nails, and the felt roofing paper from the plywood sheathing in the area to be re-shingled.
Step 3 - Get Started
Start from the lowest section and work your way up to the ridge. Apply new roofing paper onto the entire surface to be shingled with roofing nails, overlapping each course 2 inches from above.
If you are patching in a section of the roof, be sure to install shingles that match the size and the color of the existing shingles. Asphalt roof shingles are sold and installed in units called squares. A square of shingles covers an area of 100 square feet.
Step 4 - Install the New Shingles
Install the new shingles using galvanized roofing nails. Nail through the self-sealing stripe along the center of each shingle.
If you’re beginning at the eave, install a starter course of shingles upside-down with the slots facing upward along the edge of the eave. Lay the first course directly over it.
Align the bottom edge of each shingle with the top of the slots on the previous course; this usually results in a 6-inch exposure to the weather. This will also ensure that the courses run parallel. Install each new course so that the slots are aligned vertically in alternating courses.
Step 5 - Deal with Ridges, Hips, and Valleys
Shingling a ridge or a hip is done by cutting shingles into three tabs. Align and overlap the tabs so that they straddle the ridge, or hip, and drive one nail into each side.
Open valleys consist of a 6-inch strip of exposed metal flashing along the length of the valley. Closed valleys overlap onto the adjacent roof plane and are self-flashing.