Flat Top Roof Repair

Signs of Damage

• Signs of flat roof leaks can be subtle or obvious. You may notice continuous mold growth on the ceiling of an upper-floor room. A roof leak can cause deterioration of ceiling materials, with staining of the ceiling, peeling paint, softening drywall and other physical damage. Roof leaks can drip down onto walls, causing discoloration and rotting of drywall and framing lumber.

Locating the Leak

• Locating a leak on a flat top roof can be more difficult than on a pitched roof because the water travels downward on a slanted roof. On a flat roof, the water can flow in any direction, making it hard to track down, according to home improvement expert Tim Carter of the AskTheBuilder website. The best method is to start with a dry roof and check for pools of leftover water that indicate low spots in the roofing material where leaks can occur. Concentric rings of dirt on a dry roof can indicate areas where water leaks through the material. Check around flashing where chimneys or other construction meets the roof. These areas are often prone to leaks. Test the roof with water from a hose. It can take up to 10 minutes for water to drain through a leak in the roof, so be patient as you test all areas of the roof.

Repair Techniques

• Once the leak is located, clean the roof area carefully and look for cracks, splits or blistering of roofing materials. Repairs to the felt can be made after drying the roof area with a heat gun. Additional material is then added and glued with bitumen adhesive. Repair flashing with additional zinc material and glue for a tight, waterproof fit.

Repair Products

• Homeowners have a wide range of products available for roof repairs. Whole roof coatings may be necessary for some problem conditions. A rubber elastomeric coating is easy to use; you pour it over the roof material or roller it onto the surface. Additional coats may be added after the first coat has dried, depending on the manufacturer’s directions. Bitumen-based coatings can extend the life of roofs for three to five years, and acrylic coating can provide 10 years of additional roof life.