Felt must be able to absorb how many times its weight in asphalt?

Felt must be able to absorb how many times its weight in asphalt?

• A. 1 to 1.5
• B. 1 1/2 to 2
• C. 2 to 2.5
• D. 3 to 4

Answer: (B)

The main idea is how much hot asphalt a roofing felt must soak up to perform properly as a base sheet in built-up roofing. When heated, the asphalt penetrates into the felt fibers, saturating the mat so it bonds well to the layers above and below. The standard requirement is that the felt should absorb about 1.5 to 2 times its own weight in hot asphalt. This amount provides enough asphalt to fully saturate and seal the felt without oversaturation that would make the mat too heavy, stiff, or prone to bleeding. If it doesn’t absorb enough, the mat won’t be fully saturated, risking poor waterproofing and delamination. If it absorbs too much, the excess asphalt can cause weight and bleeding problems, compromising performance.

The main idea is how much hot asphalt a roofing felt must soak up to perform properly as a base sheet in built-up roofing. When heated, the asphalt penetrates into the felt fibers, saturating the mat so it bonds well to the layers above and below. The standard requirement is that the felt should absorb about 1.5 to 2 times its own weight in hot asphalt. This amount provides enough asphalt to fully saturate and seal the felt without oversaturation that would make the mat too heavy, stiff, or prone to bleeding. If it doesn’t absorb enough, the mat won’t be fully saturated, risking poor waterproofing and delamination. If it absorbs too much, the excess asphalt can cause weight and bleeding problems, compromising performance.