What is roof flashing importance?
Yes, roof flashing is necessary if you don’t want leaks in your roof. Ok, so what is roof flashing and what does flashing on a roof look like? Roof flashing is typically a thin metal material, galvanized steel is this most common material, that is installed with roofing to keep water flowing away and off the roof in critical areas. Those critical areas are where roof planes meet and create a valley or meet an upright surface like a dormer or wall. Roof flashing is also installed around chimneys, skylights, and vents.
Shelters have been constructed by human for thousands of years to protect their families and those shelters have always had roofs. The main purpose of a roof is to protect your family and home from the elements like the rain, snow, and sun. Roofs today are constructed of better materials today and can last up to 100 years or longer depending on the material.
However, even the best constructed modern roof today has weak points that can be vulnerable to leaking. That is where roof flashing becomes important. Roof flashing is critical is securing joints in areas of the roof that are inclined to get a lot of water. Areas between the roof slopes that are called valleys or around penetrations like the chimney, dormers, skylights, and vents.
What are the different types of roof flashing?
In the early days of roofing, roof flashing was a labor intensive, time-consuming part of the roof. Birch bark and other materials were used to create roof flashing or ways to were used to redirect the water flow from chimneys and other areas prone to leaks.
One method that was used is applying mortar flaunching, a large buildup of the substance, piled sloped around the chimney so the water would flow away from the chimney. Using shingles at an angle were another method used for roof flashing.
Today, modern roofing uses a common roof flashing material of flexible, thin strips of galvanized steel and there are different forms of roof flashing:
- Continuous flashing: This is the apron flashing that is one long continuous piece of roof flashing installed between a sloped roof and a vertical wall.
- Drip edges: Typically installed all along the roof eaves under the roofing felt to keep water dripping off the roof.
- Step flashing: A ninety degree bent rectangular piece installed in an overlap fashion at vertical walls to keep water from getting behind the walls.
- Valley flashing: This W-shaped metal flashing is installed on top of the roofing felt where 2 roofing angles meet creating a valley.
- Vent pipe flashing: This cone-shaped fitted metal flashing is installed into the shingles to cover areas around the vent pipes.
- Base flashing: This flashing is installed around the base of chimneys to ensure rain is directed downwards like apron flashing.
- Counter-flashing: Placed opposite of or above base flashing creating a team of roof flashing.
- Cap flashing: This L shaped roof flashing lies flat to the roof, windows, and other fittings to keep water running in the opposite direction and keep it from pooling in any cracks that may be around the fitting.
- Chimney flashing: Applied around chimneys, preventing water from pooling in the gaps between the chimney and roof.
- Saddle flashing: This roof flashing is installed around jutting beams or railing attachments.
- Skylights: This roof flashing is used for skylights that doesn’t have built-in flashing and is needed to keep from water from seeping in around the skylight and into the home.
- Kick-out flashing: This roof flashing links the gap between step flashing and the gutter system to direct water away off the roof, away from the wall and to the gutter.
Does flashing go over or under shingles?
It depends on the type of roof flashing and the purpose it is to serve. When installed where a wall begins, the roof flashing is installed on top of the shingles. Base roof flashing, however, should be installed under the shingles around the chimney and then secured to the roof. In some areas, like step roof flashing, it is alternated in layers of flashing, shingle, flashing, shingle, etc.
Do roofers replace flashing?
Yes, and using a professional roofing contractor for roof flashing installation is recommended. When a new roof or re-roofing is being installed, the roofing contractor will replace the old flashing with new flashing.
When Roof Flashing Is Corroded
Corroded roof flashing should be replaced with new roof flashing. In some cases however, roof flashing can be repaired and left in place. How do you fix roof flashing? For corroded spots and small holes, using sandpaper or a wire brush, rough over the area to be patched, then clean it off with a clean, dry rag.
Next fill the area with roofing cement and spreading it over and around the area is sufficient. For ay area larger than a 3/4 inch diameter, place a piece of metal flashing over the area, held down with roofing cement over the patch.
If you’re not comfortable climbing a ladder or working at high levels, calling a roofing contractor is recommended. Having your roof inspected by a professional once a year, things like bent, damaged, loose, or missing flashing can be addressed while the contractor is on the roof. Call 832-704-2817 today for roof flashing in Spring, TX.