Of course it is a bit more technical than that but this is the basic idea behind how felt works.
Roof tar paper 15 vs 30.
Felt paper is commonly produced with a certain number of recycled products and coated with asphalt.
Organic dry felt is made from 100 post consumer recycled material.
This means that 100 square feet of the felt weighs 15 pounds.
It was easy to use durable and even had alignment lines to help with the shingle installation.
15 lb felt paper weighed 15 pounds per 100 sq.
The difference between 15 lb and 30 lb roofing felt paper historically roofing felt paper was named for weight.
Felt paper also referred to as tar paper was the standard underlayment material in roofing for decades.
We use the 30 felt paper because i feel it is the best product for your roof.
The actual weight per square foot these days is actually less than the label says but the 15 pound.
Felt is commonly sold in either 15 or 30 rolls measuring 36 inches wide.
In our industry there are two main varieties of underlayment.
Roofing felt typically comes in 36 inch wide rolls.
This weight of tar paper may tear and tends to create holes around the roofing nails.
Those numbers are a reference to how much 100 square feet of the paper used to weigh back in the early days of its use.
It is thicker and heavier than the alternative 15 so if water ever gets under your shingles it has to work extra hard to get through the felt.
What is roofing felt.
Roofing felt comes in large rolls and installs in horizontal rows starting at the lower edge of the roof with each subsequent row overlapping the previous one.
Tar paper comes in two different weights or thicknesses.
Roll saturated felt underlayment 15 astm 4869 type i is an authentic asphalt 15 astm 4869 type i is an authentic asphalt saturated organic felt underlayment is used as a breathable secondary weather resistant barrier when applied over the roof deck prior to the installation of the primary roofing product.
15 astm 4869 type i is an authentic 15 astm 4869 type i is an authentic asphalt saturated organic felt underlayment is used as a breathable secondary weather resistant barrier when applied over the roof deck prior to the installation of the primary roofing product.
Felt paper and synthetic.
Generally speaking roofing felt is a felt paper that is soaked in asphalt and other water resistant compounds to produce a membrane.
Because it s thicker and stronger.
This offers your home protection until you can.
15 is easy to rip underfoot when installing the new roof system and ripped felt paper is useless regardless of weight.
One roofing square and 30 lb felt paper weighed 30 pounds per square.