Your Ultimate Guide to Roof Flashing
Flashing refers to a thin layer made of metal that is used to direct water away from certain roof parts such as chimneys and vertical features.
What is the material used for flashing? Professionals often use non-corrosive metals such as aluminum, lead, or steel. For custom roofs, they occasionally use copper. You can also make flashing from roofing felt, rubber or plastic.
It is crucial to seal the flashing after you install it. This action will prevent water from entering the flashing and damaging your roof. You can find a highly-respected roofing contractor close to you that is experienced and qualified to install residential flashing. If you have commercial roofing, you will also need to inspect the flashing and other components.
What is the purpose of flashing?
Roofers put flashing around roof points susceptible to water damage like skylights and chimneys. Flashing is essential to prevent water from leaking onto shingles, seams, and spaces around these features. Flashing redirects water away from the roof onto the shingles and eventually into the gutters.
Flashing is crucial for the roof’s long-term integrity. One point where water is allowed to continue entering your roof can eventually cause rotten decking (or roofing boards) and water damage within the home. This aspect could lead to tearing up the shingles or replacing many of the materials below.
When your roof leaks, poor flashing installation is a common problem. Flashing can cause decking material to collapse and is therefore covered by local building codes.
Is your roof in need of flashing?
A roofer can tell you how much flashing your roof needs. Some roof features are more susceptible to leaks than others. For example, roof valleys are where the roof and dormer walls meet, as well as skylights.
Is there any part of your roof that can create unusually high amounts of rain runoff? Is it surrounded by other surfaces, such as a chimney or roof? Professionals may require flashing to seal vulnerable areas.
Flashing: Does it go over or under shingles?
Roofers commonly install flashing underneath roofing materials such as shingles. Flashing is installed between intersecting roof edges in a roof valley to channel water down the valley. You can place shingles partially on top of flashing to allow more water to flow into the valley.
Multiple pieces of metal flashing are placed around a chimney. These flashings are usually shaped in an L and attached to the chimney using mortar which they then cover with shingles. However, it would help if you placed shingles over the flashing’s horizontal portion; you can also place flashing on top of the flashing on the chimney’s front (the farthest downslope area).
Also, you can use flashing around vents and pipes. First, you seal the tube with a watertight seal. Next, attach the metal flashing to the roof. You can lay shingles over the flashing at the roof’s highest point. However, it would help if you placed the flashing above the shingles at their lowest point. This action will allow water to drain from the flashing onto the shingles.
What types of flashing are there for roofs?
You can fit different roof features with flashing in different shapes. Examples include:
- Apron or Continuous: Metal sections that are long and often have expansion joints.
- Valley: Placed where two roof sections meet.
- Base: The downslope area of flashing installed on a chimney or other feature requiring multiple pieces.
- Counter: Used on the upslope and sides of vents and paired with base flashing.
- Skylight: Flashing is a flashing service that protects skylight seams.
- Step: Bent sections made of metal placed at the base of a wall where it intersects with a roof. Often paired with kick-out flashing, which channels water away from the wall into the gutter.
- Drip edges: Thin strips of metal placed at roof edges to prevent rain from reaching the wood surface beneath.
Professional flashing installation and maintenance
It is difficult and imperative to work with metal flashing. It can prevent costly roof damage and save you money if done successfully. However, your home or business could be at risk if you don’t install it correctly. Contact roof repair specialists, such as Roofing Repair Ashland MA, if you have any roofing questions.