One Layer Roof

The roof has varying number of layers with most areas having two layers of old shingles.

One layer roof.

When it comes to estimating the weight of an existing roof field. Ice water barrier this self adhering water proof and self sealing membrane is applied to the roof deck. Installing new roof shingles over old effectively doubles the weight of the roofing so you have to make sure your roof structure can handle the extra load. As a result you ll typically lose one quarter to one third of the roof life.

Many roof decks were designed to handle only one layer of shingles. Single ply roofing cost. Single ply roofing is priced per square foot and an average price for materials and installation of a 60 mil roof may range from 3 to 5 per square foot. A built up roof for example will typically include the built up membrane itself with or without gravel as well as some kind of insulation and cover board which will vary in thickness from roof to roof.

I have an itemized quote for a 28 square single story roof including a detached garage in los angeles ca. You can usually see the underside of plywood decking from the attic. This provides added protection against ice dams. Often there is a problem with the first layer of shingles that was not apparent.

However installing new flashings including special drip edge flashings made for reroofing will ensure a tight seal and a long life. Having an old layer of roof shingles under your new layer accelerates that process as the original layer holds a lot of heat. Chances are your roof structure was designed for a dead load of one layer of shingles plus extra for snow and a safety margin. We explain when double coverage of felt underlayment is recommended and we describe how to figure out if your roofer installed a single layer or double coverage layer or maybe no layer of felt under the roof shingles.

Note that roof systems typically include more than one type of material. The additional weight of multiple layers may also be more than the roof supports can bear. New materials are 5 500. Roofing felt underlayment layers.

It provides structure by tying the trusses and joists together. Most often made out of plywood this roof layer is installed over the framing in a typical roof install. If you intend. On the flip side removing the original roof shingle layer drives up the replacement cost so the decision is an economic one.

Double layer or double coverage roofing underlayment are defined here. Some roofers install a layer of waterproof shingle underlayment wsu over the existing shingles at the eave end as would be done for a roof laid on bare sheathing. The cost associated with the material and installation can vary widely depending on roof conditions the attachment used and the type of membrane being installed. The tear off quote is 4 000.

However some areas on the roof have up to five layers of shinles.