Wellness How-To: Our DIY Sauna

Of all the raised eyebrows we garnered from our former HGTV.com show, the DIY sauna brought forth the most questions, hands down. Where’d you put it? How big is it? How does it work? And mostly: Why on earth?

I’ll tell you Why on Earth: bliss. As it turns out, if you spend a mere twenty minutes in a hot cedar box with Chopin on repeat, you are anew. Transformed. Ready and able to take on the world yet again, or at least flip the pancakes.

Early flu symptoms? Sauna. Allergies? Sauna. An overwhelmed mind? Underwhelmed heart? Sauna, sauna.

When Ken drew up the plans for our master bath renovation years ago, he knew he could knock out a weird corner linen closet and the better part of the existing bath/shower combo to create a sauna and shower duo. But he also knew we’d need to forgo two things: storage and a bathtub.

You won’t miss the tub, he promised, and there wasn’t an ounce of me that believed him.

The thing is this: Ken’s definition of a sauna conjured memories of his family’s upper Michigan cabin, of a rich and vibrant Finnish community where everyone owned a sauna, where it was perfectly normal to sneak away for a half hour in the middle of the day to ladle fresh water onto hot rocks, take deep breaths until your mind clears, then roll in the snow and do it all over again.  Me? My definition of a sauna was the tiled, slightly mildewing steam shower at the Y.

I’ll miss the tub, I promised.

(I do not miss the tub.)

I suppose this is why I’m such a big proponent of thinking deeply about the things we keep. Of re-imagining the way we live, of what surrounds us, of asking ourselves if there’s a better solution for you and the people who live alongside of you. Could the garage be an art studio? The attic a writer’s room?

The closet a sauna?

Yes, yes, yes.

And so, if you’re itching to get creative in your own space, to ditch the rules or the tub, here’s how we (ahem, Ken) built a DIY sauna in our master bath:

STEPS

1. Frame out the space with 16″ on center 2×4 (at minimum) stud walls and whatever appropriate sized dimensional lumber for your ceiling joists. The shorter the ceiling height, the better/easier it is to heat. In our space, there is at least a 40º temperature swing from our floor to our ceiling (the ceiling is 7.5′ high). So the lower the ceiling, the more heat is at the bench. However, if the ceiling height is higher, a person has the option to build multilevel bench seating, which is a nice perk. More the merrier, and all that.

2. Decide if you prefer a wet* or dry sauna. If wet, plumb for the water spigot accordingly (for us, this meant both hot and cold, in addition to a floor drain and concrete shower pan).

3. Run the proper gauge electrical wire for the sauna stove you choose. We ran the wire all the way from the electrical box to the sauna stove, no splices.

4. Insulate each stud cavity completely with the least toxic insulation available (we used pink fiberglass batt).

5. Use a foil vapor barrier, not a plastic vapor barrier. Run barrier horizontally on the walls, starting at the rim of shower pan. Then, the next layer above it will overlap the first layer by 6″, and so on. Try not to cut (vertically) any of the horizontal runs, but if you have to for some reason, overlap the cut by one whole stud bay (at minimum 6″). When standing in the sauna after finishing the foil vapor barrier, you should be able to see nothing but the shower pan under your feet, the foil vapor barrier on the walls, and plumbing pipes (if you have chosen to go the direction of a wet sauna).

6. Use 100% silicone caulk generously. Seal between the concrete and the foil vapor barrier and run a bead of caulk horizontally around the walls at the edge between the vapor barrier layers. Caulk around any plumbing sticking through your vapor barrier, and also around all electrical wire for the sauna stove.

7. Use 16 gauge stainless steal finishing nails to hang tongue and groove cedar boards on the walls, starting with the bottom row, keeping each board level all the way around the sauna. If desired, add a small piece of cedar trim (basically a baseboard) to meet the concrete at the bottom. (Note: when hanging cedar tongue and groove, make sure the tongue is facing up and the groove is facing down. This will ensure proper shedding of water if/when splashed. Also, you can hide the stainless finishing nails if you shoot down at a 45º angle through the cedar where the tongue meets the thicker part of the board. This fastens it to the wall, while still allowing the groove of the piece above to fully swallow the tongue.)

8. Use cedar board to finish trimming out the inside of the sauna. Use that same trim board to frame all the way around what will be the door.

9. Choose your door design. While you can certainly go with a traditional insulated sauna door, they can get pricey, so we opted for a custom-cut shower door normally used for steam rooms. (Pro: This way, because our sauna is right next to our shower, the design feels more symmetrical and cohesive than a traditional sauna door.) We chose a manufactured door from Basco, then a local company measured, cut and installed the door.

10. Purchase your sauna heater. We used a Tylo Super Sport 2/4 wired 240v for a 4.5kw output (and highly recommend any Tylo heater — the customer service and quality is impeccable.

11. Build a bench. We used 2×4 cedar boards on their edge with about 1.5″ between each board to make a 2 person bench, but the possibilities are endless here!

*One note about wet saunas:  Using municipal water on your hot stones is not a good idea. Instead, buy a few gallons of distilled water at your local grocery — they’ll last weeks at a time and you’ll steer clear from  inhaling vaporized chlorine, fluoride, etc. from city water chemicals.

TOTAL COST

Once the 2×4 framing is up, the total cost was about $1350, and it costs roughly $.45 to take a 40 minute sauna (including 20 minutes to heat completely up to temp).

Tell me: what’s something out-of-the-box you’ve made in your own home lately? I’d love to hear! And if you have any sauna questions, I’m happy to wrangle my own resident renaissance Ken to answer them in the comment section!