How Many Layers Of Roof Shingles Are Allowed In Nj

Usually shingles are replaced every 15 to 20 years.

How many layers of roof shingles are allowed in nj.

Asphalt shingles typically can have one more layer added over the top two roofs total. The contractor may do a walk on the roof and also inspect from the attic for any rot before installing a second layer of shingles. In some instances 3 layers may be allowed but this is rare. For example cedar or tile roofs are only allowed one layer.

Steep sloped roof products such as tile slate metal and shakes only allow one layer. Generally it is fine to have three layers of shingle but you should check this with your local building permit people and you should make sure that your roof and the rest of the structure have the strength to cope with the extra weight. The nj home inspectors will investigate and report on how many layers of shingle are installed and estimate the remaining life of the shingles. If the third layer is new you should not have to do.

However this depends upon the roof materials. This will also be constrained by other factors. On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing. Most building codes allow up to two layers of organic or fiberglass asphalt shingles.

Regulations allow a maximum of two layers of shingles on a roof but experts say you shouldn t lay asphalt shingles over an existing roof. Most areas only allow for a maximum of two layers. That limit pertains to roofs with up to a 4 12 pitch. A roofing contractor will know exactly how many layers of roof shingles are allowed in your area for your building but it is normal that you will be permitted up to three layers of shingles.

For roof slopes of four units vertical in 12 units horizontal 4 12 or greater underlayment shall be a minimum of one layer of underlayment felt applied shingle fashion parallel to and starting from the eaves and lapped 2 inches. New jersey call 908 757 3400. In the portland area as of 2018 the current code allows up to three layers if the current layer is in good condition. For many years it was acceptable to put even the third layer.

When it s time to replace your roof there are several factors that might lead your roofing professional to recommend adding shingles on top of your existing layers.