The culprit for a leaky commercial roof is most likely a failed flashing system. Flashing is responsible for allowing the roof to repel water and other elements and if not properly installed, the integrity of your commercial roofing could be weakened. Flashing is the water barrier, sealing off joints and seams in the roof. Water-proof materials provide protection from the elements in the weaker areas, such as chimneys, skylights, and edges. Installing flashing goes a long way in preventing serious water damage to the roof and property.

Types and Purpose of Commercial Roof Flashing

Types of Commercial Roof Flashing

Flashing is available in different materials including.

  • Lead: Highly flexible and durable and one of the top choices for flashing.
  • Aluminum: Durable and inexpensive but can also corrode if in contact with alkaline materials
  • Copper (or lead-coated copper): More durable than aluminum but difficult to bend
  • Plastic or rubber: used as caulk to help propel water
  • PVC or TPO: great for roofing and flashing
  • Roofing felt: Asphalt-saturated felt is good for flashing but not the most durable
  • Galvanized steel: inexpensive but not as durable as other options

There are also different types of flashing and we can help you choose the right option based on your roofing system.

  • Bargeboard is done along sloped edges.
  • Wall Abutment, where walls meet the roof edging.
  • Cap Flashing for the uppermost edges of the base flashing.
  • Exhaust/Vent Flashing for all areas where a vent or pipe protrudes from the roof.
  • Drip Edge Flashing is used around the roof perimeter to prevent water from reaching the structure below.
  • Eaves Flashing for flat edges.
  • Valley Flashing, where two downward slopes meet.
  • Corner Flashing is done from roof to floor where the walls meet.
  • Inverted Corner Flashing wraps around the corners where the roof meets a wall.

What is the Purpose of Commercial Roof Flashing?

One of the main questions regarding flashing is whether or not it is necessary if you apply sealants. The answer is yes, it is important. Sealants can crack and lose adhesion over time, so there are definite benefits to investing in commercial roof flashing.

  • Increased property value: A roof that is constantly leaking or has a weakened structure is hazardous and not something a commercial property manager will be interested in. For a better investment and value for your property, flashing is a beneficial addition to your commercial roof.
  • Appearance: Flashing gives the roof an aesthetically pleasing, clean, polished look.
  • Weather-proofing: Flashing helps protect the roof and structure from water damage. Proper installation is essential for this so make sure you work with a professional to get the right type of flashing for your roof style and materials.


When it comes to extending the life of your roof, the installation of flashing goes a long way in reducing water damage and wear. In order for flashing to work, proper installation is important, so reach out to us today for any questions you have concerning flashing and we will help you get the right type to better protect your commercial roof.



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