Install a Metal Roof Over Existing Shingles
LESLIE: Now we’re going to talk roofing with Jeff in Tennessee. What can we do for you in your money pit?
JEFF: Well, we’ve had a little tornadic action down in this area and my house didn’t get hit by a tornado but some twisting winds tore off about three or four of the shingles. I don’t know whether to go ahead and replace a few shingles or go for a whole roof and in looking at the different available coverings for roofs I’m now looking at a metal roof and my question really has to do with something that roofing people don’t seem to be in concert about; can I put a metal roof over a shingle roof.
TOM: Absolutely. There’s no reason you can’t do that. If you had a couple of layers of shingles, just for the issue of the weight alone, I’d probably take it off and go down to the original sheathing. But there’s absolutely no reason you can’t put a metal roof on top of an existing shingle roof as long as you can, you know with good workmanship, make that metal roof look well. If the shingles are built up and it’s another inch of massive shingles on the roof and it makes it hard to flash the metal roof against adjoining sections of the roof or sections of siding, then I might consider taking the old shingles off as well but there’s no reason you can’t. Those original shingles are not going to shorten the life of the metal roof. However, if you were to put multiple layers of shingles on top of each other they do shorten the life of each other because they cause additional heat which allows the shingles to dry out. But in the case of metal roofs there’s no asphalt to evaporate so you don’t have to worry about that.
JEFF: Thank you, Tom and Leslie. It’s been a pleasure and I listen to you as much as I can.
TOM: Alright, you’re so welcome. Thanks so much for calling us at 888-MONEY-PIT.