Unlike plastic spas, the requirements necessary to build a quality long lasting wood hot tub are more extensive and much more stringent. Plastic is plastic, but each species of wood is different and they each have a unique set of qualities that may or may not make them good candidates for hot tub construction.
The type, grade and quality of the wood plays an important role in the life expectancy, beauty and maintenance of a wooden hot tub as well as your overall hot tub experience.
One of the most desirable and sought after qualities of timber for hot tubs is a clear, heart, vertical grain, but that’s just one of many properties that a timber species must possess to even be considered for use in high quality wooden hot tubs.
Natural resistance to decay is another top concern when choosing a species of wood to use for a hot tub. Different cuts from the same wood species, or even the same tree, can have vastly different rot resistance qualities.
The ability of the wood to properly swell is order to maintain water tightness is also an important consideration. The proper wood must also have an agreeable grain pattern to eliminate any possibility of warping, pealing, de-laminating or splintering. Needless to say, knots are not welcome and must be completely avoided.