2 May 2026 · 4 min
Oiling timber through a wet year
Heat-treated spruce is stubborn, not immortal. A Saturday with a brush is cheaper than a replacement stave.
Thermo wood has been cooked so that it takes on less water. It still wants a coat of oil or stain on the outside, once a year, preferably on a dry day that is not immediately followed by a week of rain. We send a tin with most buildings; after that, any decent exterior oil for heat-treated timber will do.
Pay attention to end grain, the bottom stave, and anywhere splash from a tub hits the cladding. Inside, leave the sauna timber alone unless we have specified a sauna-safe treatment. The benches should silver a little. That is use, not neglect.