What Is Flashing on a Roof?
Ever heard a roofing contractor refer to something called flashing? If so, the term may have conjured up images of something totally unrelated to roofing — that’s not what this blog is about.
Flashing is a crucial component of residential, commercial, and industrial roofs. Regardless of slope, just about every roof features this important protective component, and without it, a roof can suffer serious damage. So what exactly is this critical roofing material, and why should you care?
Read on to learn what roof flashing is, why it’s important, what the signs of flashing damage are, and what you can do to keep your roof flashing in optimal condition.
What Is Roof Flashing?
When it comes to roofing, flashing refers to thin pieces of rust-resistant metal that are installed on roofs alongside vertical protrusions, such as chimneys, skylights, dormers, vent pipes, and parapet walls. Flashing also sits in the center of roof valleys.
Most roofs feature some type of galvanized steel flashing, but copper and aluminum are also common. Generally, the type of metal used is determined by the type of roof the building has and the aesthetic the building owner would like to achieve.
What Purpose Does Roof Flashing Serve?
Roof flashing is designed and installed to prevent water from pooling in certain areas of a roof and seeping beneath the roofing material where it will cause damage.
Roof valleys — where two different planes of a roof come together — are prone to collecting water, and flashing installed in those areas helps water flow efficiently off the roof. Similarly, sections of the roof that butt up to vertical protrusions, such as chimneys and dormers, are also prone to collecting water.
Without flashings installed alongside these protrusions, water will make its way beneath the roofing material (shingles, metal, etc.). Once there, that water will slowly drip between the roof and the adjacent wall. This problem can also occur when a piece of flashing is damaged or deteriorated.
If the issue isn’t detected or is left unrepaired, the dripping water can eventually make its way inside the building, where it may damage the underside of the roof or even saturate parts of the drywall that forms the interior ceiling.
Types of Flashing
There are many different types of flashing that a contractor may install on a roof, and each type is designed to be placed in a specific area. They include:
- Step flashing. This type of flashing is essentially a rectangular piece of metal that’s bent in the middle to form a 90-degree angle. It’s typically installed in areas where the roof face meets a wall, such as at the base of dormers.
- Valley flashing. This type of flashing sits in the middle of a roof valley, which refers to the area where two different roof planes meet.
- Continuous flashing. Also called apron flashing, this type of flashing is a long, continuous piece of metal designed to direct water toward the lower portions of a roof.
- Base flashing. Certain vertical roof protrusions, such as chimneys, need this type of flashing installed on the roof deck to effectively prevent water from touching the area where the protrusion meets the roof.
- Counter flashing. This type of flashing is also necessary on many types of vertical roof protrusions. It’s installed on the protrusion itself and connects up with the base flashing to form a continuous piece of metal that prevents water from seeping behind the upper edge of the base flashing.
Signs of Roof Flashing Damage
Like all roofing components, flashing is vulnerable to deterioration and damage over time. Some of the most common signs of damaged flashing include:
- Corrosion on the flashing itself
- Minor interior water leaks near skylights, fireplaces, or dormers
- Dents or cracks in the flashings that can allow water intrusion
- Damaged seals around flashings
- Damaged or worn roofing material, which typically alludes to the presence of flashing damage as well
If you notice any of the above signs of flashing damage, contact a roofing contractor. You’ll need a comprehensive roof inspection to determine the degree of damage and the extent of the roof repairs required.
Get a Free Roofing Quote in Southern Vermont
Whether your home or commercial building is in need of a few roof repairs or it’s due for a complete roof replacement, let our team at Total Roofing & Service Inc. take care of you! We specialize in a wide variety of roofing types and services and serve residential and commercial clients throughout Southern Vermont and New Hampshire.