
Quality flashing to prevent leaks
You already know that the roof on your home is important, but what you may not realize are the many components of a roof. One of the important components that are often overlooked by many homeowners is the roof flashing.
Every homeowner should be familiar with roof flashing such as what it looks like and where it is on the roof. Then, during a regular walk around the house, if any is loose or missing, you will notice. Some roof flashing examples where flashing is used, and the purpose it services would be:
- Chimney flashing is found around the chimney.
- Continuous flashing protects between a sloped roof and a vertical wall.
- Drip edges to keep water from infiltrating under roofing along eaves, rakes, and over roofing.
- Skylights flashing is around the curbs and along the base.
- Step flashing protects where the chimney, dormers, skylights meet the roof.
- Valley flashing protects the where two roof planes come together.
- Vent pipe flashing is cone-shaped and fitted over flues and pipes.
When should I use roof flashing?
As we have mentioned here, there are many areas where roof flashing is used. Almost anywhere there is roofing, there is flashing. Roof flashing is a thin strip of galvanized steel and should be installed where water needs to be directed away from specific, critical areas. Those areas are where a vertical surface, like dormers or walls, meets the roof plane. Roof flashing should also be installed around roof features, such as the chimney, skylights, pipes, and vents.
The key areas that you should use roof flashing are:
- Continuous roof flashing: Roofers may refer to this as “apron flashing”, it is one long piece of metal that directs rainwater down to the shingles. These long pieces of continuous roof flashing will warp or work loose as it flexes each time the house contracts or expands with the weather. There are long pieces of continuous roof flashing with built-in expansion joints now that flex with that movement with being stressed.
- Base roof flashing: The chimney will require two pieces of roof flashing to ensure the rain will always be met by roof flashing and redirect it downwards. This area is difficult to install roof flashing, but there is an improved two-part roof flashing just for this area available.
- Counter roof flashing: This piece of roof flashing is positioned either above or opposite to base flashing to completes a two-part area as described above.
- Step roof flashing: This rectangular piece of roof flashing is shaped at 90 degrees from the center and is used where the walls meet the roof. Your roof should have multiple pieces of this roof flashing, installed layered the shingles to ensure the flow of rainwater is going away from the walls.
How does flashing work on a roof?
A short answer to this: It keeps your home sound and stable. How? We need roof flashing to keep the components of it from being damaged and to provide waterproofing. Without roof flashing, components like the chimney, HVAC, and plumbing pipes would be subjected to rainwater getting in around and under them. Without this roof flashing, the decking and below can become saturated, damaging the component and/or structure of your house.
How do you fix roof flashing?
Because flashing is installed at the highest points and along the edges of a roof, having a professional roof contractor do the repairs is always recommended. They will have the proper ladder heights and other equipment needed to do the job correctly.
They will carefully examine all the areas where roof flashing is installed, then remove the damaged or loose pieces. Once they have cleaned the areas, they will use either mortar or roof flashing caulk to hold down the new pieces of roof flashing.
Once that has had time to dry and set, they will caulk around the joint areas and over any lips, and around the chimney, HVAC, and plumbing pipes to make sure it completely seals the joint areas.
Should I replace flashing with a new roof?
The purpose of roof flashing, leak prevention! If you are going with the expense of getting a new roof, having a new roof flashing installed as well is a minimal part of the major investment you’re making. This only makes sense as the roofing flashing and waterproofing is like all in one and is another step in protecting the roof and your home’s integrity longer.

How long should roof flashing last?
The roof flashing on your home should last longer than the roofing material because it is made from galvanized steel. Regardless that the roofing material is guaranteed to last 15 years or longer, the roof flashing will have a longer lifespan unless it becomes damaged, loosened, or ripped off during high winds. As you protect your home with a security system of alarms, doorbell cameras, lights, and air purification systems, don’t forget the roof flashing. Your roof does a great job of protecting your home and loved ones, but it can’t do it alone! If you believe your flashing has been damaged, call Quality Exteriors, Inc. at (651) 796-2341 for flashing repair in St Paul, MN.