What Is a Roof Filler?

Function

• Roof fillers are primarily used to fill and repair tears, fissures and cracks in rooftops. This compound is also used for sealing voids and edges around penetrations. Roof filler also seals joints between corrugated roofing sheets, and acts as a water proof membrane along the edges of chimneys, ventilation shafts and drain pipes.

Composition

• Fillers typically have a putty-like consistency that make it ideal for filling and expanding in cracks and voids. Roof fillers are typically made with bitumen resins. Bitumen is a mixture of hydrocarbons used in asphalt and other roofing materials. Because bitumen is used for waterproofing surfaces, asphalt in roof fillers reinforces watertight surfaces. Other roof fillers include rubber latex and water-based acrylics such as copolymer.

Benefits

• Roof fillers protect roofs against rain, snow and other weather conditions. It also adheres well to roofs made with both natural and synthetic materials. For example, latex foal fillers can be used for repairs on wood, drywall, concrete and brick masonry, glass and plastics. These fillers can also be applied indoors and outdoors depending on the brand. Some fillers offer finish-ready surfaces that can be painted, sanded and stained to blend with surrounding decor. Other roof fillers offer protection against ultraviolet rays.

Application

• Before applying filler, remove debris, loose cement and broken tiles from the work area. Use a spatula to apply over voids and cracks along roof ridges, and a paint brush to smooth off excess filler. Apply filler along corners where the ridge and roof tiles meet. For broken roof tiles, use the spatula to apply a generous amount of filler before reattaching the broken pieces. Added roof filler should be dry before sanding or painting.