A cedar shake roof is the most popular type of roof covering, and it offers greater insulation when compared with asphalt shingles. It's also considered to be one of the most long-lasting and attractive of all roof coverings, but mistakes are often made in installing this type of roofing that should be avoided. Some of these mistakes and some pro tips for avoiding them are listed below.
Determining your Shingle Requirements
In estimating how many shingles you'll need, do not make the mistake of trying to estimate the number of shingles until you have figured the square footage area of your roof. Then, use that figure to estimate the number of shingle "squares" you'll need.
Square Foot Area Formula
Don't try to estimate the entire roof area all at once. Estimate the square foot area of each section, separately. Then add them together. Begin by measuring the roof width and roof height on one section of your roof, then multiplying the two numbers. A section that is 30' long, for example, and is 20' from eaves to the peak will be 600 square feet. Use this same formula to figure each section. Add the total of square feet, add 10 percent for waste, and then divide this number by 100. This total will then be the number of squares you'll need.
Missing Nails and Loose Shingles
You'll need a solid surface for your new shingles, so don't begin installing the new shingles until you have replaced any missing nails in the old shingles and have nailed down all old shingles that are loose.
Excessive Roofing Layers
For a roof with more than three layers of shingles, or for one whose shingles are not in good condition, don't make the mistake of installing new shingles until you've first removed the old ones. Use a crowbar, nail bar, or roofing shovel to loosen the old shingles. Remove these old shingles and loose roofing nails from the roof. Then, lay down a layer of roofing felt.
Installing the Cedar Shingles
Start nailing the new shingles at the lower edge of the roof. Inexperienced roofers often make the mistake of placing the bottom edge of this first shingle row even with the roof edges. You'll need to overlap the roof edges by 1-/12 inches or more. An even more serious mistake you should avoid is placing the thick end of the shingle on this first row at the bottom of the row. For this row only, place the thick end at the row top. On each shingle drive in two nails, one inch from each side and 4 inches down from the top of the shingle. Do not butt shingles together. They need space to expand. Keep a space of ¼ inch to 3/8 inch between each shingle.
The Peak Row
When you've installed shingles from one row down from the peak, stop here. Never finish installing your top row until you've laid down a layer of roofing felt on the peak.