15 came perforated for use as a ply sheet for built up roofing.
15 or 30 felt under metal roof.
Most codes and good roofing practice would require felt.
Felt roofing underlayment is typically available in two types.
No 15 felt and no.
Once again this is used on cold roof construction.
Of course it is a bit more technical than that but this is the basic idea behind how felt works.
The best weight for roofing felt is the 30 pound product because it provides thicker and.
The difference between 15 lb and 30 lb roofing felt paper.
In my opinion felt paper is a vapor barrier plus keeps the oils in the shingles from leaching out and into the wood substrate i e.
Felt paper is commonly produced with a certain number of recycled products and coated with asphalt.
The main advantage of using felt roofing underlayment is cost.
With metal roofing its also a good idea to put a layer of red rosin paper between the felt or ice water.
That is the quesation.
The house is in eastern tn.
One roofing square and 30 lb felt paper weighed 30 pounds per square.
The best underlayment for metal roofs.
This type of underlayment is critical to a quality roof installation.
Make sure the product is designed to be used under metal.
Felt is commonly sold in either 15 or 30 rolls measuring 36 inches wide.
Plywood or osb roof deck so 15 20 or 30 will work for any shingle roof the type i recommend depends on roof slope.
Historically roofing felt paper was named for weight.
Generally speaking roofing felt is a felt paper that is soaked in asphalt and other water resistant compounds to produce a membrane.
It serves as a moisture barrier as well as a slip sheet.
When hot roof construction is done a roof with no ventilation a breathable underlayment is recommended.
15 lb felt paper weighed 15 pounds per 100 sq.
Felt paper or not under metal rofing.
Traditionally metal roofs have used standard 30 pound felt paper underlayment.
What is roofing felt.
There are several types of felt underlayment including both organic reinforced and inorganic reinforced.
The traditional and most common material used for roof underlayment on a steep slope metal roof is non perforated asphalt impregnated felt underlayment.
Asphalt saturated heavy duty roofing felt is available in 15 and 30 pound weights.
Other say need felt because of sweating and it will root the osb 30 felt or not.
Underlayment must also act as a secondary weather barrier in case the roof fails.