Usually, when talking about roofs, we focus on the shingles. Asphalt shingles make our roof looking nice and resist the weather action. Though, other elements like roof flashing also play a critical role in these systems.
What is Roof Flashing?
Roof flashing is a thin, metal sheet, which drives water away from seams and joints. Moisture and humidity could filter through these points, causing water damage.
The purpose of flashing is to avoid water getting under the shingles in critical areas such as:
Places where the roof surface meets a wall
Low points where two roof slopes meet
Roof protrusions (bathroom/kitchen vents, skylights)
The roof’s edges (rakes and eaves)
Also, flashing is placed around any exterior joint where water should runoff, such as windows, doors, chimneys, gutters.
Types of Roof Flashing
Base Flashing & Step Flashing:
Base flashing and step flashing go where vertical walls intersect the roof deck.
Base flashing is one length of flashing that is bent (along the length) to match the pitch of the roof. It goes installed over underlayment and under siding and shingles. Then, you may not see it from the ground.
The base flashing stops the water blown against the home walls during windy storms. It avoids the water getting between the wall and the shingles and directs it into the gutters.
On the other hand, we have step flashing.
They are installed along the total length of the sidewall, where it joins the roof deck. Pieces of step flashing are bent at an angle relative to the roof pitch. Likewise, the flashing should be partially exposed along the wall.
Step flashing does a better job of protecting against leaks than continuous flashing. Besides, it ensures that water drains safely with minimum risk to your roof.
Valley Flashing
Valleys are those lines surging from the intersection of two different roof slopes. Rainwater flows into the roof valleys. So, in these places, water penetration is more probable. There is where valley flashing gets into action.
Metal valley flashing goes between the underlayment and the underside of the shingles. The shingles over each section of the roof do not touch, forming a gap that exposes the valley flashing. Thus, water runs off on the valley flashing towards the gutters.
Chimney Flashing
Sealing joints between the roof and elements such as chimneys, vents, and dormers are complicated. Each of these penetration points demands particular materials and installation techniques. Besides, waterproofing these locations is always critical.
In this regard, Jeff Frantz, Washington D.C. territory manager for CertainTeed Roofing Products, explains:
“Using proper flashing components and maintaining penetrations like skylights are critical to the performance of the roof as a system,”
Drip Edge Flashing
Drip edge directs water at the edge of your roof so that it won’t get under your shingles, preventing the wood at the edges from getting rot. Roofers install it at both the rake edges and the eaves edges of the roof.
During strong winds, shingles tend to lift along the rake edges. Thus, flashing wrapped at the rake edge gives additional protection.
Also, the drip edge at the eaves protects the fascia board from water coming from clogged gutters or ice dams.
Roof flashing
The right type of flashing for your roof will depend on the type of your shingles and your home style. Your roofer should tailor your roof flashing to your roof’s unique features.
Skylight Flashing
This type of flashing prevents moisture from getting on the surface of your roofing material without relying on sealants that can break down.
Installing skylight flashing is indispensable to avoid roof leaks at a skylight. Without it, you may suffer water filtering, roof rot, corrosion, mold, and damage to your home structure.
Continuous Flashing
Sometimes, continuous flashing is seen where the sidewall and roof meet. It is installed in a long run of flashing to prevent leaks in this corner space.
You may think that a single, continuous piece of flashing will offer more protection than several pieces. But, the truth is completely different. If a small section of the roofing cement fails, the complete continuous flashing will fail. So, you’ll have a leak spreading easily.
If your roof system includes continuous flashings, you can replace it with something more reliable, like step flashing.
Kick-out Flashing
Kick-out flashing redirects rainwater and moisture away from your home cladding and into the gutter system. So, they receive the name of diverter flashing. When installed correctly, it prevents unwanted water infiltration.
Missing or faulty kick-out flashing causes large accumulations of water and grave damage to your home’s exterior walls.
What Materials Are Used for Roof Flashing?
Usually, homeowners know less about flashing materials than types of shingles. So, here’s what you should know about the different materials available for roof flashings:
Copper: Currently, this is the most durable flashing material. Besides, it’s very eye-catching. It doesn’t tend to develop rust, even after years of exposure, and looks great with different roofing styles. Also, it doesn’t require painting or regular treatments to remain effective.
Steel: Galvanized steel is a popular flashing material that works very well with metal roofs. Typically, steel flashings come with a zinc coating to protect them against corrosion. This feature gives them longer durability under exposure to weather elements.
Lead: Lead has long-lasting resistance to water damage. It can expand and contract with the outside temperatures easier than many other materials. Besides, this type of flashing is believed to last for more than 200 years.
Aluminum: This is a relatively inexpensive, malleable, and durable flashing material. Due to its malleability, it is an excellent option for trickier sections of a roof. However, it corrodes easily when exposed to weather elements.
Does Roof Flashing Ever need to be Replaced?
The only way to guarantee completely that your flashing will work properly is to replace it. Nevertheless, many flashings outlast the typical lifespan of a roof. Therefore, you can reuse them if they’re in good shape.
But, if your flashings have suffered weather damage or show signs of wear, you should replace them.
Are You Holding out for a Hero to Save Your Roof?
Call Alpha Roofing at 318-373-5830 or visit us online to request an estimate. A licensed professional will come to your home for a free, no-obligation assessment. We can replace your old roof with a beautiful new roof with up to a 50-year warranty in Bossier City, or Shreveport, LA!