Blackstone Exteriors

Flashing may cover small parts of the roof, but the role they play is not to be underestimated. But how do they work, exactly? Read on as the local roofers at Blackstone Exteriors take a look at this key roofing component.

Types of Flashing

Flashing is the material that protects the vulnerable areas of the roof, such as joints, penetrations and transitions between areas. Because of constant exposure to the elements, sealants like caulk are not ideal for use in these areas. A typical sloped roof would have a combination of the following types of flashing:

• Valley flashing is what most people recognize as flashing. It protects roofing valleys, as flowing rainwater tends to converge in these areas. Standard valley flashing has a profile shaped like an upside-down “T,” forming a vertical barrier that prevents cross-infiltration between planes. Some roofing manufacturers use long strips of material similar to shingles.

• Continuous and step flashing are installed on walls, dormers and similar parts of the roof. Continuous flashing protects the sides of these areas that run parallel to the roof’s edge, while step flashing is installed on the sloped side. It’s installed in steps, similar to shingles.

• The drip edge is a long strip of metal that protects the roof edge. Its inverted “L” profile counters the capillary action that causes water infiltration at the edge and facilitates flow into the gutters.

• Rubber boots, also known as vent pipe flashing, are cone-shaped pieces that protect the base of vent pipes and other tube-shaped components that penetrate the roof. Before installation, the pointed end of the cone is cut to fit the pipe’s circumference. Rubber boots are available in various sloped bases to match the roof’s slope.

Does Flashing Need Replacement?

Flashing takes a lot of wear and tear. This is why roofs need new flashing at least once during its expected life span. They can get dislodged by wind, impact from hailstones or other airborne objects, or by unusually strong flow of water. Rubber boots, being made of rubber, can degrade with continued exposure to heat and UV radiation from the sun.

Keeping up with annual maintenance conducted by a roofing professional, as well as keeping an eye on your roof through regular visual inspections, can help ensure the integrity of your roof’s flashing.

Haven’t scheduled your roofing inspection yet? Give your local roofers at Blackstone Exteriors a call  at (515) 720-2158. You can also fill out our contact form to schedule an appointment.