Sauna Construction
Sauna Construction
Framing Considerations for Pre-Cut Packages
1A. Framing for Horizontal T&G Application
The entire sauna should have 2x4 framing on all four sides and the ceiling. If a portion of the sauna is solid wall construction (brick, block, etc.) those walls should be framed with vertical 2x2 firing strips of standard 2x4 framing. All framing should be standard 16 inches on center.
1B. Framing for Vertical T&G Application
If you plan to install your tongue and groove vertical, you have two framing options. Method 1: Install 2x2 or 2x4 nailer between studs. For 7 foot high saunas, evenly space and fasten four levels of nailers between the top plate and base plate of your walls. Method 2: For standard 7 foot high saunas, evenly space and fasten six 1x2 firing strips across the studs.
2. Baseplate
We recommend that the base plate be constructed of treated 2x4’s for added protection against moisture on the floor. All other framing can be made of any suitable framing material such as SPF grade 2x4’s. The floor should be a waterproof surface such as tile, linoleum or concrete.
3. Ceiling Framing
The ceiling height should be framed at 7 feet or less (minimum of 75”) off the floor. If the ceiling is currently over 7 feet, it should be dropped for proper sauna performance. Generally, 2x4 ceiling framing is adequate. In the case of a height of 8 feet or more, consider using 2x6 lumber.
4. Corner Studs
Be sure you have a stud in each corner of the room to allow fastening of the ends of the tongue and groove boards. 
5. Framing the Doorway
Make sure to frame your doorway perfectly plumb and square. Frame the left and right sides with a double 2x4 for extra strength. For a standard door, create the rough opening 2 inches wider and 2 inches taller than the door size ordered. For a standard wood door measuring 24”x80”, the rough opening should be framed to 26”x82”. NOTE: If you have a handicap (ADA) door, consider leaving the base plate clear for wheelchair access.
6. Framing for Air Outlet
The outlet vent should be located diagonally across the room from the inlet vent (or as far away from the inlet as possible). The opening for the outlet frame should be the same size as the inlet (6”x4”), with the top of the opening 23 inches off the floor. To ensure minimal loss of heat, it is not recommended that the outlet be installed any higher than 30 inches from the floor. Again, use an existing stud for one side of the vent and additional 2x4’s to frame in the vent.
7. Framing for Heater Mounting Bracket
Determine the location of the heater in the sauna as recommended by your sauna representative or as described by your heater installation instructions and template supplied with the heater. Add two 2x4 support beams between the studs for the heater brackets.NOTE: The metal heater hanging brackets are installed after the tongue and groove installation. The height and location of the supports is determined by the mounting instructions supplied with the heater. The supports are not necessary when using the optional floor stand for commercial floor standing heaters.
8. Electrical Rough-In
Once the sauna is fully framed, and before the insulation is installed, the electrical rough-in should be done by a licensed electrician.Warning: Follow wiring instructions provided with the heater. Always use proper wire size and type as specified in your heater instructions provided in your heater box.
9. Insulation
Using 3 1/2 inch thick fiberglass batts, insulate the interior walls of your sauna by tucking it between the studs.Note: Un-backed batts are best to prevent a double vapor barrier which could trap moisture. If you only have backed insulation keep the paper/foil side to the interior of the room. For the ceiling use either a single layer of 6 inch fiberglass or you may wish to use a double layer of 3 1/2 inch fiberglass. To do this, hang the first layer perpendicular to the ceiling joists and then pound nails into the bottoms of the joists and hang the second layer on the nails between the joists.