What You Need To Know About Low Sloped Roofing
Low sloped roof systems can be prone to leakage then steep pitched roofing systems. To be successful the low sloped roofing material needs to be impermeable to water almost like a wet suit. Traditional asphalt shingles do not work on low sloped roofs because they are not water tight. They are a shedding system that uses the slope of the roof to shed water from its surface.
If you have an almost flat roofing system you should periodically inspect the roof for damage, splitting and cracking. Often the most vulnerable area in the flat roofing material is its seams. The older the roof gets the more brittle the seams become.
Ponding or pooling water on a flat roof system is another big leak generator. Even the smallest hole will allow water to enter the home or building. If water is collecting on your roof its time to call a flat roofing professional.
Poor flashing details are often the cause of leaks in flat roofs. Roofing cement should not be used as flashings. It will dry out crack and allow water to enter the home or building.
Look for cracks in the surface of the roof, often cracking of these roof membranes takes on the appearance of alligator skin. “Alligatoring” is a common wear indicator and excessive cracking indicates the need for a roof covering replacement.
There are several types of low slope roofing material:
Rolled roofing: Which is the least expensive and has the shortest life expectancy of any of the materials. The life expectancy off rolled roofing is only ten years. This type of roofing consists of one layer of asphalt applied over a matt surface. The top of the roof is usually covered in granular material and the seams are usually sealed with roofing cement.
Rubber membranes:Many of the roofing manufactures are making rubberized types of roofing membranes for low slope roof applications. Some of these membranes have self adhering backs. Others are installed with hot asphalt or by using torch down methods. These types of roofing systems have a life expectancy of roughly 12 years.
Built-up roofing: Built up roofing is a material made up of overlapping rolls of coated mats, with layers of bitumen (rubber like material) placed in between the rolls. There is general a layer of granular material installed on the top of the roof surface. These type of flat roofing materials have a life expectancy of fifteen to twenty years depending on the products.
There is nothing wrong with buying a home or building with a low sloped roof, however regular inspections are required and an understanding that these roof systems are generally more prone to leakage and have a short life expectancy.
I will be looking for low sloped roofing defects while performing your New Jersey Home Inspection.