roof flashing around pipe penetration

What Is Roof Flashing and Why Does My House Need It?

This is a great question. Roof flashing is an extremely important part of a roof’s drainage system and is used with all types of roofing materials. Even flat roofs need flashing along edges, walls, penetrations, and valleys. In short, if your home has a roof, that roof should include flashing to protect your home from leaks that lead to damage in your attic, ceiling, walls, interior, and exterior.

Roof flashing is a strip of galvanized steel or aluminum that we secure over all joints in the roof. Joints refer to where two surfaces come together. Flashing also guides rainwater toward gutters or otherwise off the roof. 

Common locations for flashing include where two slopes meet. We call these areas valleys. Flashing is placed over shingles in valleys and roof ridges so that rainwater and moisture don’t enter the joints. We use sealant or butyl tape to seal the edges of roof flashing. With asphalt shingles, the flashing can be covered with shingle tabs for a more appealing look.

Other areas where flashing is placed include but are not limited to:

  • Chimney pipes
  • Skylights
  • Vents
  • Dormer walls

When to Install Roof Flashing

Roof flashing should be installed when a roof is installed, but because roofers in Texas don’t require a license, anyone can put on a roof or even have a roofing installation business. A roofer who’s unfamiliar with the proper way to install roofing components may not place flashing at all, or may not place and secure it properly. If flashing was left off of your roof, it can be installed beneath existing shingles. 

Roof Flashing for Other Areas

We prefer to place drip-edge flashing along a roof’s perimeter and gutter apron flashing to keep water from entering behind a gutter. Drip-edge flashing runs along a roof’s eaves, those edges that are parallel to the ground. Shingles extend beyond a drip edge by about a ½ inch. Rake edge flashing is placed around gabled edges of a roof. Roof flashing in these areas protects underlayment and soffit boards.

Flashing Failure

The main cause of home leaks is roof flashing failure. Over time, flashing can warp and bend as a structure settles. Texas heat takes quite a toll on a roof! Some flashing material rusts. Oftentimes, when flashing fails, the roof needs replacement anyway due to other issues. However, if your roof outlasts the flashing, the flashing can be replaced.

Interior Home Damage Due to Damaged or Missing Roof Flashing

Small holes in roof flashing may be caused by animals or corrosion of the material. Flashing with holes, warping, or bending due to weather and age will allow rainwater and snow or ice melt-off to seep beneath shingles and into the wood. This leads to damage you can see inside and outside of your home, like:

  • Water stains on ceiling and/or walls
  • Softness to sheetrock
  • Water stains near windows, fireplaces, skylights
  • Wood rot and moisture damage in your attic
  • Damaged exterior siding
  • Dark spots or moisture on insulation or wood
  • Mildew, musty smell
  • Mold growth
  • Rusty nails indoors, poking through the paint/texture
  • Wet carpet or flooring
  • Water seeping from baseboards

When water enters your home, it can lead to extensive and expensive damage. Fortunately, ROI works with homeowner’s insurance, so we can help you find out if insurance will pay for all or part of damage caused by a leaky roof.

Your Next Step

If you notice water stains or moisture in your home or attic, or if you’re concerned about the health of your roof flashing, call me, Chris Duty, for a free roof inspection. I can identify problem areas and talk with your insurance adjuster, if necessary. My crews repair and replace roofs and roofing components (like flashing) in the Dallas-Fort Worth Metroplex. 

Call or text me at 682-337-1849, or email [email protected] to schedule your roof inspection. ROI also offers carpentry, masonry, electrical and plumbing repair, demo and replacement of walls, cabinets, and other interior structures. We offer flooring, windows, doors, and painting, as well. Call me, and let’s improve your home’s appearance, health, and value!