Understanding Flat Roofs and Their Repairs
A flat roof, in roofing terms, is not entirely flat. It’s a roof with a minimal pitch, typically between 1-10 degrees. This slight slope ensures water can flow off the roof into a gutter system, preventing pooling and water damage. While most commonly found on commercial and industrial buildings, flat roofs are also used for residential patios, home extensions, and garages. Flat roof repairs are less expensive when they are caught early.
Various roofing systems are employed for flat roofs in the United States, including TPO, EPDM, Modified Bitumen, PVC, and Built-Up Roofing (BUR). Each of these systems has unique materials and installation methods:
- TPO Roofing: A single-ply membrane made from synthetic materials and reinforcing scrim.
- EPDM Roofing: A durable rubber membrane primarily composed of ethylene and propylene, similar to materials used in tires.
- Modified Bitumen Roofing: Multiple layers of roofing felt applied with hot asphalt.
- PVC Roofing: A flexible single-ply membrane made from polyvinyl chloride (plastic).
- Built-Up Roofing (BUR): Consists of layers of bitumen topped with aggregates like gravel or small stones.
Challenges Flat Roofs Face
Like any roof, flat roofs are not immune to damage or leaks. Weather is the most significant factor affecting roof longevity. Yearly threats such as high winds, hail, heavy rain, storms, tornadoes, hurricanes, and temperature extremes test the durability of roofing systems. Despite advancements in manufacturing, repairs are inevitable.
Flat Roof Repairs: From Simple to Complex
Flat roof repairs can vary widely—from minor fixes to extensive replacements. A small issue, like a screw loosening, can lead to significant damage over time. In severe cases, such as a fallen tree limb damaging the roof, large sections might need to be replaced. The type of repair often depends on the roofing system:
- TPO and PVC Roofs: Repairs require trained professionals with the right tools and materials.
- Rubber Membranes: Small holes or punctures can be addressed using rubber sealant. First, clean the area with a solvent, then apply the sealant. Sealant is typically available in tubes (similar to caulk) or cans, and applying it may require a putty knife and utility knife.
For more extensive damage, like bubbles or blisters, use a utility knife to carefully open the affected area, ensure it is dry, and then apply roofing sealant before adding a patch appropriate for the roofing material. Adhesive-backed patches are convenient solutions for synthetic membranes.
- Built-Up Roofs (BUR): For damage, cut away the affected area, apply sealant or tar, smooth it out, and place a patch over the damage. Add more sealant and finish by topping it with matching aggregate material for a seamless repair.
Key Takeaways
Flat roof repairs depend largely on the roofing system and the extent of the damage:
- Use adhesive patches for minor damage on rubber and synthetic membranes.
- For asphalt-based flat roofs, sealant combined with bitumen is the go-to solution.
Whether the issue is small or large, addressing flat roof damage promptly is vital to maintaining the roof’s integrity and preventing further problems.