Metal roof over existing shingles

Leigh McArthur
5/18/2011
Hello, I have owned my home for 20 years and have been notified by my insurance company I had to replace the roof to keep coverage. Something about the life usefulness. Anyway, I have always wanted a tile roof but was told the tile was too heavy for my roof. I saw the metal roof designs here that resemble tile. So here are my questions. (Oh, I'm not a contractor or roofer and do not know all the terms you may use. So bear with me please.) Does the metal tile have to be installed special? Is it eligible for the energy tax credit? Can it be installed over my existing asphalt shingles? Does anyone actually know how to install the metal tiles, or is it a specialty item that cost an arm and a leg to install? Thanks
Todd Miller
Classic Products, Inc.
5/18/2011
There are specific installation methods for these products and I encourage you to contact the manufacturers and find out who in your area has installation expertise. Some of the tile facsimile products I believe are eligible for the federal tax credit. Installing these products over a layer of asphalt shingles should not be a problem in most circumstances. All Best.
Info @windowsonwashington.net
An informed customer is our best customer.
5/19/2011
Most of the metal tile profiles that are available today are very well thought out engineered. Whether or not a given profile can be installed over top of shingles depends largely on the manufacturer and their guidelines. The cost of these materials is appreciably more than asphalt shingles, however, this should be expected as you are getting much, much, much more roof for your dollar. Tax credit eligibility depends on the emissivity of the color/panel. The weight of metal panel systems is far below concrete or clay and your roof structure should more than handle it. Your installer will certainly need to be skilled to install this profile but most people that work with metal possess the skill set to properly install this type of system.
Guest User
10/27/2011
What issues are there for applying over existing tar and gravel (2.5:12 slope)
Todd Miller
Classic Products, Inc.
10/27/2011
Many metal roofing profiles are not designed for use on pitches under 3:12. Also, if you go over the old roof you will need to clean off the gravel and / or use some sort of recovery board to smooth thing out, plus you will want to put down underlayment.
Guest User
10/27/2011
Sounds like to do it right, it is really better to strip off the old down to the sheathing. Put another way, if it was your roof, you'd strip the old tar and gravel, then install underlayment, and then metal roofing that is approved for 2.5:12 slope. Summarizing from other posts, if the attic space is ventilated below the eaves, permeable underlayment isn't necessary, and something like Grace Triflex or GAF tigerpaw would be acceptable, correct?
Todd Miller
Classic Products, Inc.
10/27/2011
Antony -- you're good. I agree with everything you're saying. :-)
Info @windowsonwashington.net
An informed customer is our best customer.
10/28/2011
Agree 100% as well. Penny-wise and pound-foolish to not strip the roof in my opinion.

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