Roof Vapor Retarder

Gaf sa vapor retarder is an sbs modified bitumen vapor retarder for use in approved gaf roof assemblies.

Roof vapor retarder.

Typically a vapor retarder has to have a perm rating of 1 0 or less to be successful. The need for use and design of a vapor retarder in the design of a roof system used to be a hotly debated topic. Sopra vi is a bitumen coated base sheet for use in approved built up roof assemblies. The topside and underside are.

When we use a vapor retarder in a roof system it will also act as an air barrier as long as it is sealed at all perimeters and penetrations and is tied to the wall air barrier. It appears now when vapor retarders are needed more than ever the design community seems to have lost interest which is not good considering how codes and standards altered through concerns for energy savings have changed how buildings are designed constructed and operated. In a low slope roof assembly the vapor retarder is normally installed under the primary roof insulation. This eliminates the need for a separate air barrier that could potentially prevent the moisture from escaping.

Sopra vi is composed of a proprietary formulation of bitumen and is reinforced with a high quality random glass fiber mat. Everyone knows that water in roof systems is never a positive.