Do-It-Yourself: Re-Roofing a House
Roof shingles are designed to last a finite amount of time. When their life expectancy ends or the shingles are damaged by a natural disaster, they must be replaced correctly to ensure it does not leak. Each part of the installation is crucial to the overall performance and strength of the new roof shingles.
Working at heights presets dangers at every turn. Using the correct equipment in the correct way will significantly reduce the chances of an onsite injury. Extension ladders are the most common way to climb onto a roof. The end of an extension ladder must extend at least 3 feet past the roof eave to allow you to step off the ladder safely. In addition, ladders require a 11 1/2-degree pitch to eliminate the chances of the ladder falling away from the roof while in use.
Scaffolding is the next most popular means of working on a roof. All scaffolding must be tied into a stable structure with tie lines to keep it in place during use.
Remove Existing Shingles
Place the tines of a four-prong pitchfork flat on top of the shingles. Slide the end of the tongs under the lip of one shingle course. Push the handle of the pitchfork forcefully under the shingles. Push the handle toward the roof to separate the shingles from the roof sheathing. Discard the shingles as they are removed. Do not allow them to sit on the surface of the roof or the planks of a scaffold.
Inspect Roof Sheathing
Walk the roof after all shingles and felt paper are removed from the surface of the roof sheathing. Tap the tines of the pitchfork on the sheathing as you walk. Mark any soft or rotted parts of the sheathing with a grease marker. Be careful not to step on any roof sheathing before checking its strength with the pitchfork. Replace all damaged sections of sheathing before proceeding with the application of new shingles.
Apply Roof Felt
Roll out 15- or 30-pound felt paper on the entire surface of the roof. Start at the bottom with the first layer of paper and work toward the roof peak. Overlap each course of felt paper 4 to 6 inches to ensure a leak free installation. Secure the felt with roofing nails or staples placed every 6 to 8 inches. Install new drip edging over the eave end of the felt paper--if required.
Install Starter Course Shingles
Mark the centerline of the roof from the peak to the eave with a chalk line. Cut off the tabs of a few pieces of shingle. Set the shingle on the felt paper. Allow the bottom of the shingle to overhang the drip edge by 1/4 inch. Secure the shingles with nails or staples placed every six inches. Make sure the staples run through both the shingle and the metal drip edge flange. Install all starter course shingles.
Layout Shingle Course Locations
Allow the bottom of the next shingle course to overhang the starter course by 1/4 inch. Install the shingles using the same nailing pattern as the starter course. Keep all nails above the tar tabs located in the middle of the shingle. Measure up five inches from the center of the installed course of shingles and make a mark on the felt paper. Snap a line at the mark to show the top edge of the next course of shingles. Measure and mark every five inches until the entire roof has a series of horizontal lines sitting five inches apart.
Apply Roof Shingles
Align the top of a new roof shingle with the lowest marked horizontal line. Secure the shingle to the roof. Move along the roof installing the new roof shingles along the layout lines. Alternate the starting point of each course to ensure the seams between shingles do not line up. Install the cap shingles over the eave or hip -- hip roofs only.