How Many Layers Of Roof Shingles Are Allowed In Ohio

Finally consider whether reroofing over the old shingles is even allowed where you live.

How many layers of roof shingles are allowed in ohio.

Shingles are the element that most homeowners are familiar with as it is the layer you can see from the outside of your home and it is an important aesthetic aspect. That limit pertains to roofs with up to a 4 12 pitch. For instance ohio code chapter chapter 4101. The soundness of the building you re re roofing is another consideration.

However this depends upon the roof materials. In the portland area as of 2018 the current code allows up to three layers if the current layer is in good condition. 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. In snowy climates most new roofs these days get an ice and water shield a rubbery moisture membrane applied to the sheathing along the eave to protect against ice dams.

For many years it was acceptable to put even the third layer. For example cedar or tile roofs are only allowed one layer. Most building codes allow up to two layers of organic or fiberglass asphalt shingles. 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.

Adding a second or third layer of shingles adds significant weight to the structure. 3 tabs are less expensive but also less durable have lower wind resistance and have a flatter appearance. Most cities and towns allow a maximum of two layers of shingles says chad muth president of muth company roofing in westerville ohio. Section 1511 3 requires that roof replacement shall include the removal of all existing layers of roof coverings down to the roof deck but it does lay out a series of exceptions.

On most flat roofs such as epdm tpo or modified it is perfectly acceptable to two layers of roofing. The bottom layer shall be 18 inches 457 mm and the top layer a minimum of 36 inches 914 mm wide. Asphalt shingles come in two major types 3 tab and architectural. For closed valleys valleys covered with shingles valley lining of one ply of smooth roll roofing complying with astm d 6380 and at least 36 inches 914 mm wide or types as described in item 1 or 2 above shall be permitted.

Asphalt shingles typically can have one more layer added over the top two roofs total. Steep sloped roof products such as tile slate metal and shakes only allow one layer.