How to Replace Asphalt Shingles
When asphalt shingles are loose or missing, you can easily replace and refasten them. And as long as you’re on the roof, inspect the others close up, as well as the flashing, to find out whether any shingles are damaged or likely to cause problems in the future.
How do you know a shingle is damaged? Telltale signs are when the grit on top of the shingle starts coming off (you find the sandy substance accumulated in the gutter), tabs are missing, or you’ve got twigs, leaves, or something else wedged under a shingle.
To fix the shingles, you need a pry bar, a hammer, galvanized roofing nails, a utility knife, roofing cement, a caulking gun, silicone caulk, a screwdriver or nail puller, and some matching shingles. If you don’t have replacements, take a damaged shingle to the home improvement store and match it as best you can. One bundle isn’t expensive and will probably be enough for current and future repairs.
Before looking for loose and damaged shingles, replace the ones that blew away in case it rains before you finish the job. Here’s what to do:
Take off shingles just above the patch.
You should go two rows up and be careful that you don’t damage others when you take them out.
Use a screwdriver or nail puller to raise the nails in the bare spot.
When a shingle is loose, it dries out, and after time, the bottom edge of the shingle begins to curl. Loose shingles are more likely to fly off in the next windstorm.
Starting at the bottom, put a new shingle onto the bottom row, overlapping the one below it.
Be sure to follow the line of the rest of the shingles in the row. Your patch will shout, “Look at me,” if it angles up the roof.
Nail the shingle to the roof, using galvanized nails.
If you can’t reuse the holes, fill them with roofing cement. You should also cover the nail head with cement. You don’t want to leave holes in the roof because water will seep in and damage the wood underneath.
When you get to the last shingle, cut off the nail strip on top with your utility knife.
Put roofing cement on the back of the shingle and slip the replacement under the shingle above it. Press both shingles firmly
Plan to work when it’s moderately warm outside; shingles get stiff and hard to handle when it’s too cold. And on hot days, the shingles will be so hot that you will damage those on the roof just by walking on them.