Best Wood for a Sauna

Traditionally saunas were made from wood sourced locally so it was often not a choice of wood based on quality but best on availability. There are many different types of wood available to build a sauna room, but the number one rule when selecting wood for a sauna room is to stay away from knotty wood. Knots in wood are much denser and often bear sap. Because a knot is a different density it will shrink and dry at a different rate than the rest of the wood. This causes the wood to warp and twist and also there is a good chance the knots may fall out.

No stain! Whatever wood you select for a sauna room be sure you leave it natural. Do not add any stain to the internal wood. This can cause harmful VOC's to be emitted in the sauna. Safe sauna sealers are available that are 100% water based, but never use any oils or latex stains on the inside of a sauna room.

Stay away from cheap lumber. The old phrase "you pay for what you get" hold very true in building a sauna room. Stay away from cheap woods such as Hemlock and Aspen. While they may look good and are price about ½ of cedar, they simply don't have the same characteristic that are needed in a sauna room. Cedar is naturally resilient to decay, it has long straight fibers that avoid twisting and checking and is very light and fibrous, meaning it does not heat up. If possible, use cedar when buying a sauna kit. Almost 100% of commercial saunas are made from cedar simply because it is the best wood for sauna construction both for indoor saunas and outdoor barrel saunas.