Does Faced Insulation Need a Vapor Barrier?

Vapor Blockers
Once insulation gets wet, it's hard to dry it out. ... Not every type of insulation needs a vapor barrier. But if it does, the barrier should face inside in northern, heating climates, and outside in humid southern climates.

Is it OK to put plastic over faced insulation?

More than likely, installing an additional layer of poly over kraft facing won't cause any problems — it's no more risky than if the wall had only unfaced batts and poly — and the risk of using poly on the interior is relatively low in a cold climate like New York's.

Does faced insulation act as a vapor barrier?

There are two basic types of vapor barriers used with exterior wall insulation. The most common is paper-faced insulation. This type of insulation has a Kraft paper face with two flanges. ... This is very important — the paper, which is the vapor barrier, always faces the warm side of the house.

Robert Thorne

Robert Thorne

Automotive & Future Transportation Editor

Robert Thorne covers electric vehicle innovations, autonomous driving systems, global mobility trends, and automotive engineering developments.