Single Layer Roof

In a single coverage felt installation the lower edge of each course overlaps the previous course by a minimum of 2.

Single layer roof.

Single ply membranes can be generally categorized into two groups. It is common practice to add a second layer of shingles over an existing single layer provided the roof decking is intact and the roof surface is flat. This provides added protection against ice dams. That s because on roofs like the one in the photo with slope of 4 12 or greater only a single layer of felt is required under asphalt shingles.

Most shingle warranties do not apply when shingles are layered over existing roofing according to internachi. Foot commercial roof it will usually cost between 3 50 and 7 50 per square foot in materials and labor to for a tpo membrane. Why roof shingles work best in single layers the temporary savings you receive from adding a second layer of shingles does not outweigh the negative aspects. They work well for a variety of projects with roofs of all shapes and sizes including exposed roofs green roofs cool roofs ballasted roofs and more from large scale commercial projects such as airports and factories to a private house rooftop.

Single ply roofing installation methods. A new buyer won t pay you a dime more just because you have one roof layer instead of two. Single ply roof membranes are one of the most popular flat roofing materials ideal for lightweight cost effective fast track construction projects. Click to enlarge any image.

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. Chances are your roof structure was designed for a dead load of one layer of shingles plus extra for snow and a safety margin. As for whether or not shingles last as long as a manufacturers warranty promises the answer is probably yes but only if the installation and maintenance are absolutely perfect. For an average 20 000 sq.

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. But check the shingle warranty from your shingle manufacturer. Single ply roofing cost. Single ply roofing basics types of membranes.

The type of installation for the single ply roofing will depend on each. The membrane roof is the latest roofing technology and is also the roof of choice in. Modified bitumen cap sheet roofing was developed in the 1960s as a replacement technology for. That can be either architectural shingles or conventional 3 tab shingles.