As an alternative to electric-heated hot tubs or even propane-heated hot tubs that both require some sort of hook-up to utilities, a wood-heated hot tub is an easy and affordable way to heat the water in a tub, especially if the tub is set far from any utility hook-ups. Choosing the best wood-heated hot tub comes down to one key decision: a heater that is placed fully outside the water, or a heater that is placed directly in the water. A heater placed directly in the water will heat the water more quickly, but one placed outside the tub will not take up valuable space in the tub.
Wood-heated hot tub models are often made from cedar walls, which naturally insulate the heated water. The wood heater may be placed within the water, and the metal sides of the stove that are heated from within will heat the water quickly and efficiently. Such a heater, however, will take up a significant amount of space within the tub, which means there will be less space for bathers. If cost efficiency is your primary goal, choose a wood-heated hot tub with a heater inside the water. It will heat the water quickly and keep it warmer longer, but keep in mind that some space will be lost, and some ashes may escape the stove and end up in the water.
Other wood-heated hot tub models feature a wood stove outside the actual structure of the tub, which means no space within the tub is lost to a heating element. Most versions of the wood-heated hot tub with a heater outside the tub feature small wood stoves that are connected to the tub by a series of tubes. The tub water travels through these tubes to the stove to be heated, and then returned to the tub itself. The water will take longer to heat up using this method, and it will not stay as warm for as long as a model that sits inside the water, but such a system allows for more space within the tub and less worry about stray ashes floating into the water.
When choosing a wood-heated hot tub, choosing a good cover and the best materials are vital. Cedar is the material of choice for wood-heated hot tubs because cedar is naturally resistant to mold and rot, as well as warping or bubbling. It is water-resistant and naturally beautiful as well. It insulates the water well, which is vital to keeping the tub warm throughout the time it is being used. Be sure to consider a good cover as well, as this will prevent heat loss when the tub is not in use and keep debris out of the tub water.