Heat dissipation & important stuff to know if your sauna is outdoors or made with thin wood.
Just like in the walls of my Bullfrog hot tub I want the walls of my sauna to be well insulated to maintain the temperature while not overstraining or overworking the heaters. Cheaper saunas may use less insulation so I always make sure to inquire about how thick the fiberglass insulation is and also what it’s “R” value is which is an industry rating that defines its ability to keep heat in. An "R13" rating is fine for sauna walls while "R22" to "R26" is required in the sauna ceiling. As with typical home construction, sauna walls and ceiling must be insulated and protected with a vapor barrier.
Typical vapor barriers are made of plastic, which would quickly degrade (possibly used in cheaper saunas), outgas, and even melt from the heat of the sauna. It is vital, therefore, to use an aluminum foil vapor barrier instead of plastic. This is an even more important point of contention if the sauna will be put outdoors where it will be sitting in wet or humid conditions parts of the year.
Even if the sauna has good insulation, it may not have enough infrared heat power to keep it hot enough (how I like it) when outside exposed to cool or even freezing conditions which is usually the time of the year when I love to warm up. So how will the A brand perform indoors? How will A brand perform outdoors? Sometimes there is a difference.
Sometimes a sauna needs to have an extra extension cord going out to it to supply more power for additional heaters when outside and not all brands have this option by the way.
The key question to ask: Where was the sauna tested, at the manufacturing facility? Did the manufacturer’s specifications for the heaters, thermostat and sauna unit itself come out of being tested on the factory floor or what about in the snow, sleet, rain, fog, drizzle, or shmizzle? What about the shmizzle!!?! Where are my specs about its shmizzle rating!? Note: Shmizzle is not an officially recognized term by the National Weather Institute. I was shocked to find out that a lot of brands never tested their sauna in outdoor real world conditions! What a crock of..
I don’t want to be feeling under the weather about my sauna purchase cause I’m sitting outside under the weather literally and can’t get my sweat on!!
Deep breath now on my oxygen concentrator..
The bottom line is how can a sauna have almost its entire set of walls covered in carbon panels and another sauna have half or less that many or other saunas that have a few small ceramic heaters…Will all of them hold the temperature the same? To confuse things further they all seem to be priced similarly. There is proof available so I make sure to ask for it.
Besides insulation and heater strength how the wood boards are laid out can help to prevent heat dissipation. The minute I step into a sauna to evaluate it I always look at how the boards are laid out. Horizontal boards are preferable over the older vertical style because they make the sauna room look larger and create a better seal of the tongue and groove.
With an outdoor sauna, make sure there are no municipal by-laws in the area that restrict the size and location of the outdoor sauna. If locating the sauna outside it’s important to build a foundation below the frost line to avoid damage from heaving when the ground thaws after the winter months. Something important to factor into your sauna budget.
Note: Thin walls dissipate more heat. 3/4 inch thick is the thickest wood used in saunas I have found and holds more heat than the 1/4 and 1/2 inch wooden models.
Thin walls are much more likely to warp, crack, chip, splinter, twist or develop bows over time