Asphalt shingles have become more attractive over the years. No longer are you limited to the standard black or gray asphalt shingle. Now, you can find asphalt shingles that look like wood, slate, and even like asphalt.
Two Methods of Asphalt Shingling
There are two ways to roof a house with asphalt shingles. The first way is by completely removing all the existing shingles. The second way is to lay a second layer of asphalt shingles on top of the existing layer.There are arguments for and against both methods. The main argument against laying additional layers of asphalt shingles is that the roofing materials can get too heavy for the underlying roof framing. And this can be a real problem, especially for older houses. In fact, it is often said that a triple layer of asphalt shingles is equal to a single layer of slate roofing materials. And if you know slate, you know this is pretty heavy.
The main argument against stripping off the existing layer and then laying down a new layer is that youre adding more work to the process. Not a real problem if roofing professionals are tackling the jobthey can strip most roofs in a morningbut if youre doing the job yourself, it can be rough.
Double Laying Means Repeating Current Problems
One other problem with shingling over existing shingles is that you are essentially repeating some of the surface irregularities that may already be there. If youre contemplating putting on a new roof, theres probably a good chance that you may have bubbles, bumps, and waves that you need to get rid of. Putting new shingles over that doesnt do much for the aesthetic aspect.One way to minimize this problem is to go over the old roof and correct as many problems as you can. It doesnt take much more than a hammer, some roofing nails, and a handful of shingles to correct the problem of bumps, gaps, and protruding nails.

