What Is a Baffle on a Roof?

Function

• Keeping your home energy-efficient begins with proper construction. Attics must have ventilation to keep the flow of outdoor air steady, cooling it down and preventing ice dam formation. Wind baffles are also known as rafter vents or venting chutes and allow insulation to cover the outside wall plates and keep insulation from blocking soffits and vents. According to the Environmental Protection Agency, the most common mistake made by homeowners when installing attic insulation is to block the air flow at the eaves with insulation.

Types

• Wind baffles are constructed from different materials, such as foam board, cardboard or plywood. Baffles are typically stapled to the roof decking and are placed on the attic ceiling, where the attic ceiling meets the attic flooring. Most wind baffles are 4 feet in length and either 14 1/2 or 22 1/2 inches in width.

Uses

• Once wind baffles are in place on your roof decking, you can add insulation to your attic to keep your home adequately insulated. Installing wind baffles also keeps your insulation in place when wind blows up through soffit vents. Placing wind baffles on your roof decking allows insulation to be placed right up to the floor of the attic. Sealing all air leaks inside your attic will also make your home energy-efficient.

Summary

• Wind baffles keep air flowing through your attic, preventing ice dams and mold growth. These vents keep the dew point inside your home steady, which keeps condensation from forming on your drywall and causing mold growth. Ice dams are caused by attics that are too warm. When snow melts from a warm roof, then re-freezes at the gutters it can cause ice to build-up and damage the structure of your roof.