All our products are made from Scandinavian spruce or thermo treated spruce
Our saunas, summer cabins, camping houses are NOT insulated.
As you are aware, natural wood is material that is cut, dried, and processed with various technologies and can but not necessarily slightly deform itself due to climate and environment.
Also, all wooden saunas, summer cabins, camping houses due to no continuous heating in them can but not necessarily get stains of dampness, mould, or discolouring.
NONE of the above reasons would ever damage whole construction/unit/building.
We do give 4-year warranty to wooden constructions & 2-year warranty to heaters.
If you do have any concerns and/or questions, please do contact our team for more information.