SAUNARI by Sieraj 01 Indoor Sauna — 4-Person, with Heater

A sauna Radek Sieraj designed around his own ritual — the 2023 Sauna Master World Vice-Champion and 2026 Polish Champion knows exactly what a cabin has to deliver for a session to truly count. By Sieraj 01 is a 4-person indoor sauna: a compact thermowood cabin with a Harvia electric heater included and an interior built for real, regular sauna sessions — not for an Instagram photo.

Who it's for

For 2–4 people who want a sauna at home — in a basement, garage, utility room or a dedicated corner of the bathroom. Made in the EU and ready to run from day one: no hunting for a heater, no piecing together stones.

What's included

• 4-person thermowood sauna cabin
• Harvia electric heater
• Heater stones
• Benches and backrests ready for assembly
• Assembly and start-up instructions

Material and craftsmanship

Thermowood — timber that has undergone thermal treatment to remove resin and boost resistance to moisture and the high temperatures around the heater. The result: a stable structure that doesn't warp through heating and cooling cycles, and never burns against the skin the way untreated wood can. Manufactured entirely in the EU, to Radek Sieraj's specification.

The sauna ritual is more than temperature — it's the first löyly, the scent of warm wood, the moment of stillness after water hits the stones. By Sieraj 01 gives you the stage for it: a cabin small enough to heat up quickly and economically, yet roomy enough to invite the people closest to you.