Polyurethane foam


Polyurethane Foam is spread by coating Outdoor Hot Tub with at least 50 mm of foamed polyurethane. Main properties of the material are:

  • Low thermal conductivity: allows keeping water warm in the Outdoor Hot Tub and creates an additional barrier against cold.
  • A solid, seamless coating that blocks cold air passages.
  • The possibility of uniform coating shape surfaces of any complexity.
  • Low hygroscopicity. You improve the waterproof performance of the surface alongside with its thermal insulation.
  • High vapor permeability that allows removing excess moisture through walls, preventing the mold appearance.
  • Does not support burning (self-extinguishing)
  • Long service life – up to 25 years


Polyurethane Foam for Outdoor Hot Tub is a particularly important and effective accessory!

Polyurethane is a modern inorganic material that keeps heat well, and at the same time, it is not subject to decay, mold growth, and damage from rodents and insects.

Baltresto sells only a fully isolated Outdoor Hot Tub! It means such construction where foam is sprayed directly on Hot Tub Liners, under the frame lining. Not only does this Polyurethane Foam coating keep the heat inside, but it also adds some structural support to Hot tub liners, which extends the service life of all components.

The insulation prevents water from cooling down and keeps heat inside Outdoor Hot Tub. Our 100% hermetic insulation system stops moisture or cold air from penetrating into Hot Tub, so it increases the speed of water heating and reduces its cooling.  Thus, the use of Polyurethane Foam significantly reduces maintenance costs and the wear-out of heating elements.

The choice of an effective thermal insulation system depends on how often you use your Outdoor Hot Tub. Click here to read the article in our blog, where we considered different options of accessories for keeping water temperature as well as saving energy and heating time.