The Importance of Properly Installed Flashing

What is flashing and why does it matter? Flashing is an essential protective strip, usually made of metal and applied in areas where a roof meets a wall, or joint, and around a chimney or along the edge of a roof.

The whole point of flashing is to prevent water from seeping through roof joints into walls, or under shingles and tiles.

The best materials won’t provide protection unless they are installed properly.

In recent years, developers have been sued over shoddy construction that allowed water to seep into walls, causing structural damage and mold. That has placed added emphasis on doing the job correctly from the start.


What are Flashing Materials Made of?

The choices are varied, depending on the application.

Metal flashing includes:

  • Aluminum
  • Copper
  • Lead
  • Stainless steel and
  • Zinc alloy

The list goes on when you consider metal with coating, like anodized aluminum, galvanized steel and lead-coated copper.

In order to mitigate any distortion or bending, metal flashing should come with expansion joints, especially on long runs of material. An expansion joint, in this case is a flexible closure used to stabilize the stress on the long length of flashing used along the roof edge.

Then, there’s the flexible flashing products like butyl rubber, rubberized asphalt, and acrylic. The list also evolved to include peel and stick tape flashings and flexible nonstick flashings. Many of these flashings are made from modified asphalt or rubberized asphalt, or rubberized bitumen.

Why Does the Material Matter?

The big difference between metal and flexible flashings is this – flexible flashings can’t be exposed to the elements for long-term water-resistant protection, like metal can.

There is some debate about whether continuous metal flashing is the best option or if step flashing is the way to go, but many factors come into play.

You’ll want to be sure your roofer understands what flashing materials work best with the type of roofing materials you’ve chosen (shingles vs. clay tiles or slate). Other factors include the climate in your area. Some flashing works best in dryer, desert regions to withstand sun and heat. In coastal areas, salt spray can cause corrosion, so coated aluminum, copper and stainless steel are best.

When repairing a damaged section of roof, the flashing in that area will probably need replacing, too. Some homeowners think that if their flashing doesn’t “look” bad or damaged, they can avoid replacing it and save on repairs. The building code states that all flashings should be changed when a roof is replaced.

In addition to finding a roofer skilled in the installation process, you’ll want to work with a roofer who is familiar with the various materials and their application.

Our professional staff can answer your questions. Contact us today to get advice.