Bitumen Roof Shrinkage

The installation process known as torch on roofing is often used on commercial.

Bitumen roof shrinkage.

Roof shrinkage is no easy matter to deal with. A few decades ago unreinforced rubber roof systems were plagued by shrinkage problems but thanks to technological advancements and improvements to epdm roofs the problems have diminished. The swelling of the underside of the shingle is commonly due to the migration of excessive amounts of airborne moisture from the attic spaces through the roof deck and into the bottom surface of the shingle. Shrinkage of a membrane often damages base flashings or the roof edge assembly leading to water infiltration.

It is most common on epdm or modified bitumen roofs and is usually caused by aging of the material poor installation or excessive uv exposure. Thanks to technological advancements and improvements to epdm roofs though shrinkage has diminished significantly. The more obvious sign of roof shrinkage are highly visible gaps running along the seams where the roofing surface rolls were initially laid out. Methods recommended for preventing shrinkage include adhesion of the whole roofing system and peripheral attachment of the membrane to the deck.

The shrinkage of the top surface is commonly due to normal aging and weathering of the shingle over the years. Shrinkage is most common on epdm or modified bitumen roofs. An organic felt or fiberglass mat saturated with asphalt and faced with granular stone aggregate. Asphalt roll roofing or membrane is a roofing material commonly used for buildings that feature a low sloped roof pitch in north america.