Paper Under Roof Tiles

The industry standard minimum underlayment for a tile roof with a slope of 4 12 or greater is a single layer of astm rated 30 felt paper.

Paper under roof tiles.

30 astm d4869 type iv felt paper or approved equal shall be applied shingle fashion. The industry standard for tile roofing in short is one layer of 30lb astm roofing felt paper. In the early days 30 pound felt was the most common underlayment used under tile roofs. Water shield is the next roofing layer that creates a water proof barrier where ice or water can buildup near the roof eaves.

Cheaper felt paper without an astm rating widely sold in home centers is much thinner and should not be used. Because your roof deck might not lie perfectly straight or flat a layer of roof paper gives an even uniform surface upon which you can install your shingles. The underlayment is a layer of paper that helps keep the seams of the roof from leaking. The practice of lining roofs with a permanent sheet roofing underlay has become a universally accepted practice in the uk over the last fifty years and people are now asking.

Underlayment installs on top of the subfloor and provides an ultra smooth surface for linoleum or vinyl flooring. The tile roof institute installation manual says that on 4 12 roof slope 33 slope or greater a single layer of astm d226 type ii no. What underlayment s should i use for my tile roof. Is roofing felt waterproof the sheeting or sarking felt is laid over the supporting rafters or counter battens and beneath the tile or slate battens.

It can help prevent the picture framing effect or the pattern of your wood decking telegraphing through your shingles by providing an extra layer on top of uneven wood. It also helps to protect the wood of the roof and helps the top layer such as shingles tile or metal to adhere to the roof. Floors that require underlayment also benefit from building paper. Most roof decking is made from sheets of plywood.

Roofing paper comes in several different types depending on what the paper is going over and what is going over the paper. Today most contractors use a minimum 40 felt we use a g 40 modified underlayment. This underlayment is far superior to a 30 pound felt and is warranted by the manufacturer for up to 20 years if installed by a tile roofing institute certified contractor. However there are cases where the roof does need to be repaired due to leaks caused by slipping or broken tiles or a worn out underlayment.