The rain can be a big problem for any roof. Too much water inside the building interior can damage the overall structure and integrity, which can be dangerous and expensive to repair. Flashing is a waterproof layer that helps prevent this in common leak areas such as joints, vents, and chimneys. Flashing is not the same thing as caulk that is used around windows and doors but it provides a similar service.

Roof Flashing Types and Purpose

Flashing Materials

Flashing comes in a variety of materials. There are two important factors to consider when choosing the best material for your roofing system.

  • Materials need to be compatible so flashing does not degrade.
  • Material needs to be impermeable to water.

The most commonly used materials for flashing include.

  • Aluminum: inexpensive, durable, and easy to work with. This should not be used with concrete or treated lumber, as contact with these can corrode aluminum flashing.
  • Copper: Both copper and lead-coated copper are used and are highly durable. They are not as easy to form as aluminum but their durability makes them a popular choice.
  • Galvanized steel: The most affordable option but not as durable as other material choices.
  • Lead: Lead is one of the leading materials used for flashing as a result of its high durability and flexibility.
  • Plastic or rubber: These materials are mostly used for caulk but when properly applied as flashing, they are great water-repellents.
  • PVC and TPO: These are used in roofing systems and can be used for flashing as well to keep roofing systems consistent.

Flashing materials are typically sold in rolls to be cut and shaped at the roofing site. You can also buy pre-molded flashing for vents, chimneys, and pipes that are a standard size.

Types of Flashing

The roofing system you have will determine which type of flashing you need. There are a number of flashing options to choose from for your commercial property.

  • Bargeboard: used along sloped edges
  • Cap flashing: used to protect uppermost edges of membrane flashing
  • Corner flashing: placed where walls meet, from roof to floor
  • DCF (drip cill flashing): placed at the foundation of the roof
  • Drip edge flashing: used around roof perimeter to ensure water flows off the roof
  • Eaves flashing: used when there are flat edges, along the full length of the edge.
  • Exhaust flashing: Placed anywhere that a vent or exhaust is sticking out from the roof.
  • Inverted corner: Use this flashing where a wall meets a roof, around a corner. It is applied between the structure and the wall.
  • Ridge flashing: Used for the peak of a sloped roof
  • Saddle flashing: Used where joists meet the walls, around the connection points
  • Step flashing: Used when the roofing materials and flashing are placed overlapping and down a slope.
  • Valley flashing: Used for the place where two downward slopes meet.
  • Wall abutment: Place this flashing anywhere that the walls meet roof edges.

What is The Purpose of Flashing?

When products such as sealants are available, many people wonder why they even need flashing. Along with the fact that sealants may not last as long, there are a few benefits to having flashing on your roof.

  • Increased property value: Nobody likes a leaky building, plus repairs for water damages can be expensive. Tenants of a commercial property will want to know their business is safe and this means having a waterproof roof. The right flashing keeps the building safe, which makes it more valuable to everyone.
  • Better looking roof: Flashing adds a polished look to your roofing system so it is more aesthetically pleasing. Adding flashing is an affordable and effective way to spruce up your property’s appearance.
  • Weather protection: Flashing is a proactive way to keep your roof protected from weather. Not having flashing leaves your roof exposed to the damage wind and rain can cause.


Your property is an investment and you want to protect this. With properly installed flashing, you can prevent serious water damage and leaks while also improving the appearance of your building. Reach out to us today for your flashing options and installation because your protection is our priority.

For any questions or to schedule a roof inspection, contact us today!