How Roof Flashing Works

Whether it is loose roof flashing or missing shingles, getting them repaired or replaced is important to the integrity of the roof and your home.
broken arrow oklahoma roof flashing installation

What is Roof Flashing?

When you hear the phrase, roof flashing, it probably doesn’t mean much to you. We know that a roof is designed to provide shelter and it’s where we hang holiday lights. Many homeowners don’t realize that there are many components to a roof, much less understand what roof flashing is and what purpose it serves. A roof is made of rafters, decking, felt, shingles, and most important, roof flashing.

  • What does flashing mean on a roof?  Roof flashing seals the roof at joints, like where the roof line changes heights, along the chimney, around attic vents, including roof flashing to gutter system.  These are areas of the roof that are highly susceptible to leaking, and roof flashing is essential in preventing that leaking.  
  • Does a roof need flashing? Yes! Without flashing to seal those joints described above, the rain, snow, and melting ice can begin leaking into the attic, down the walls, and into the house. A house where there is roofing without flashing is simply a stage for big problems in the future.
  • What are the different types of flashing? There are various types of flashing, which we are going to briefly describe here:


For a pitched roof, there are two different types, depending on the roof pitch and steepness, as well as what type of material is used for the roof. There are the double-lap flashings, which is used on roofs with plain tiles or slates with a 30-degree pitch. And there is a single-lap type flashing that is used primarily with contoured tiles roof material. It is placed next to the wall first and then the tile.

Apron Flashings

Apron roof flashing is the simplest type of flashing and is used when on lean-to roofs where they meet a wall. The top edge is placed where two courses are joined above the head and then overlapped on the roof covering.

Chimney Flashings

This is a tricky roof flashing because a portion is placed against the chimney stack sides and folded around the sides, then covered with the double-lap style or the single-lap style. A gutter is then created along the chimney’s back wall to build an up stand that is covered by another piece of flashing on the back wall. The back-gutter portion is made to follow the roof pitch and overlaps any tiles that are above it.

While we’re talking about chimneys be sure to properly maintain your roof and gutters for the cold Tulsa winter.

Valley Flashings

This type of roof flashing is used when two roofs meet at an angle, but they are less common than the other types listed above. Boarding is built to run down the roof pitch from the ridge to eaves, securing the fillets along the long edges. It is then dressed so that the roof tiles or slates overhang.  

roof flashing broken arrow ok

Frequently Asked Questions

  • Does roofing felt go under flashing? Roofing felt is placed in overlapping layers, starting from the bottom of the roof line and working upward. This will direct water to run over the roofing and under it.
  • How do you know when to replace roof flashing? Industry experts advise having roof flashing inspected twice a year. This inspection can catch possible problems before any leaks happen and cause unwanted havoc and unneeded expenses. Additionally, if roof flashing is missing, rusted, or appears to be loose, it should be replaced. Whenever a new roof is installed, the roof flashing should be replaced as well.
  • How much does it cost to replace roof flashing? Depending on the area where you live, and the size of your house will be the deciding factors what roof flashing cost. The type of flashing is also a factor in pricing roof flashing replacement. As we covered earlier in this blog, there are various types of roof flashing: Abutments, Apron Flashing, Chimney Flashing, Valley Flashing.

As soon as you notice any damage to your roof, it should be addressed immediately. Whether it is loose roof flashing or missing shingles, getting them repaired or replaced is important to the integrity of the roof and your home.

Even the smallest leak can be an indication of something bigger. Especially as we head into springtime when hail and high winds are frequent and the wintertime as well when we experience a lot of ice and snow.

A licensed roofing professional will assess the problem you are aware of, look for any other issues that you may not see, and advise you the best way to handle the situation.

Always get two or three estimates and opinions, get the quotes in writing, and check references. The time you take to do this can be what saves you money and time later.

Need to get started on roof flashing repair or replacement today in Broken Arrow, OK? Call 918-259-0877 for Prestige Roofing and Remodeling!