Since moisture can be a roof's worst enemy in the northeast, roof flashing is intended to prevent water leakage and extend the overall life of the roof. Although it sounds high-tech, roof flashing is nothing more than a piece of sheet metal that is usually made from aluminum or galvanized steel. It is often strategically placed over joints in the roof and wall construction in an attempt to further prevent the entrance of water into the home. This is especially important considering that one of the main causes of roof leaks is a fault in the roof flashing.

Roof flashing is based on a simple engineering concept that relies largely on the force of gravity. Assuming the roof flashing has been properly installed, gravity will help the flashing material direct water to the roof and then to the ground. Most roofs have roof flashing around the chimney, plumbing vent stack, fan vent, or other items that stick out from the roof.

Although there are some environmental concerns about the bulk use of heavy metal required for roof flashing, there are several qualities about the material that are environmentally friendly. According to the Lead Sheet Association, lead roof flashing is both recyclable and extremely durable with a lifespan of 500 years. Considering the fact that many modern materials have a lifespan of up to 20 years, roof flashing appears to be an environmentally-efficient selection.

For the most effective use of roof flashing, the material must be resistant to weather, highly durable, low maintenance and sturdy. The latter quality is especially important because many roofing materials regularly expand and contract on a daily basis, and more dramatically during seasonal weather changes. During the day, the sunlight can raise the surface temperature of the roof, which results in expansion. However, this temperature drops significantly at night, which results in a contraction of the materials. More significant expansions and contractions during seasonal changes can have an effect on the framing lumber, which means that roof flashing must withstand all of these changes to effectively prevent leaks.

Because roof flashing can often endure several stresses due to extreme weather conditions, extra care must be taken during installation to keep flashing material in good condition and capable of withstanding damage. Many professional roofers will cut and shape their flashing materials from sheet metal; however, homeowners can also choose to have the flashing pre-formed. It's highly important to use flashing materials that are prone to rust, such as steel.

To make sure your flashing is intact and most effective call your Boston roofer or New York roofing contractor.