Installing Sauna in Lower Level Bathroom
is a good project for a room that your finishing off or adding on to. In fact, they're pretty common in basement situations like ours. And now saunas come in a variety of different packages to fit your situation.
The sauna we installed came as a pre-cut package. We supplied the manufacturer with our dimensions, and they cut all the boards to length and labeled them for the wall they went on. Then they sent them along with the pre-hung door, benches, heater, thermometer and other accessories.
It's best to finish your framing first, and then get the dimensions you need so your boards will fit exactly.
Our boards were a Western Red Cedar which is pretty typical for an "Americanized" sauna; traditional Finnish saunas are made from Nordic White Spruce.
We insulated the walls and ceiling; this is critical for keeping the heat in and for saving energy. Then we covered the insulation with a foil vapor barrier. This reflects heat back into the sauna, and keeps moisture from condensing in the insulation.
The boards are tongue-and-groove so they fit together nicely. We just nailed into the "tongues" at an angle and then covered them up with the "groove" of the next board. We checked the boards with a level every so often to make sure we were staying on track.
NOTE: You don't want any exposed metal in a sauna because it'll get hot and you can burn yourself.
We put in two glass panels to help open up the sauna area so it wouldn't feel so crowded. They were actually double-glazed glass panes with stops on both sides to hold them in place.
There were trim pieces and molding provided to give the corners a finished look.
The benches were also pre-built, we just needed to screw in the supports that they sat on. The supports had tapered ends so you don't see them under the benches.
This sauna will be large enough for 4 to 5 people, but the benches were designed so two people could lay down at once.