But contractors who spoke with angie s list say best practices call for stripping the roof down to the wood deck to inspect it before installing a new roof.
My roof has 4 layers.
Most cities and towns allow a maximum of two layers of shingles says chad muth president of muth company roofing in westerville ohio.
If your roof is in good shape but has some damage to one side from a downed tree or has lost shingles in a wind storm an overlay is worth considering.
On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing.
This other carrier would charge me quite a bit because i d only have homeowners insurance with them and they re supposedly the only ones who will deal with me concerning the roof.
Roofing material is where most homeowners focus their attention with hundreds of materials styles and color to pick from.
Here are the pros and cons.
The five main types of roofing materials are asphalt shingles cedar shakes concrete or ceramic tiles metal sheets and rubber used for flat roofs.
First of all multiple layers of shingles simply means layering a new asphalt shingle roof on top of the old one rather than stripping the roof completely to expose the sheathing and replacing it with new shingles.
It provides structure by tying the trusses and joists together.
It must be installed the full length of all valleys.
Steep sloped roof products such as tile slate metal and shakes only allow one layer.
Decking most often made out of plywood this roof layer is installed over the framing in a typical roof install.
If it needs to be replaced the insurance policy will only cover the replacement of the top layer.
For many years it was acceptable to put even the third layer.
On 4 12 or greater slopes the balance of the roof shall be one layer of 15 felt.
I was told by my insurance company that they don t cover a roof that has three layers of roof shingles on it so i ve gone to another carrier for an estimate.
Stripping away the old roof more expensive because of the additional labor and materials peeling off the old roof down to the sheathing is your only option if you already have two layers.
If the roof has multiple layers typically the insurance company will only insure the top layer.
I have a 1949 1600 sf under roof with 8 12 pitches valleys and hips 2 6 rafters on 16 on center sheathed with 3 4 center matched lumber going over at least 1 layer of 3 tab shingles a partial tear took off the old tabs and left a nice wavy surface in pretty good shape.
So let s say we have a hail storm and the roof takes a beating.
Asphalt shingles typically can have one more layer added over the top two roofs total.
Most building codes allow this but is it a good idea.
You can usually see the underside of plywood decking from the attic.
Here are the layers of a roof in order of application bottom to top.
