Guide
Vapor Barrier Science for Indoor Saunas
Sauna heat creates high vapor pressure. If moisture gets behind the cedar walls, it will rot your home's wood framing. Here is the science of aluminum foil vapor barriers.
Aluminum foil vs. plastic wrap
Plastic vapor wraps (Visqueen) melt at sauna temperatures. Indoor builds require heavy-gauge aluminum foil wrap, which handles 200°F and blocks all water vapor transmission.
The essential 1-inch air gap
You must nail furring strips over the foil before attaching cedar. This creates an air gap that allows the cedar to dry out and stops heat conduction directly into the wall studs.
Recommended models
Ready when you are
Bring real heat to your home.
Get a personalized quote — equipment, freight, and install — in one business day.