- Whether building your own sauna saves money depends on what you count. The materials are only part of it: the wall build-up, the heater circuit and your time are where a DIY sauna succeeds or fails.
- Outdoor sauna kits with a heater were listed from $4,499 to $15,299 in August 2026. KLAFS's retractable S1 was listed at $44,900 to $51,900 at its US launch in July 2026.
- Before you buy, ask what is in the wall: R-value, insulation, vapour barrier, the tape that seals it, and whether any adhesive is used inside the hot room.
- Either way, the heater needs a 240 V circuit from a licensed electrician and the permits that come with it.
What buying costs.
These are prices brands published for outdoor saunas with a heater included, captured in August 2026. Backyard Discovery's Lennon cube for four to six people was $4,499. Redwood Outdoors ran from $6,899 for its six-person Vista to $11,699 for its eight-person Grove. Coldture's PRO was $12,399 and its XTREME $15,299.
At the top, KLAFS publishes few prices. Its retractable S1 was listed at $44,900 to $51,900 when it launched in the US in July 2026, with delivery and installation extra. Its made-to-measure models are priced by quote.
What to check before you buy.
Insulation. Ask for the R-value of the walls and ceiling. Backyard Discovery is one of the few brands that publishes it: 30 mm walls with an estimated R-1.4 to 1.8. The minimum we recommend for a sauna wall is R-12, with R-16 in the ceiling.
The vapour barrier. Ask whether there is one, which side of the insulation it is on, and what seals the seams. Ordinary aluminium tape lets go at sauna temperature; foil tape rated for 120 C holds.
Adhesive. Ask whether any glue is used inside the hot room, in panels, boards or benches.
A published spec. Few sauna sellers publish a wall assembly at all. If a seller cannot tell you what is in the wall, you cannot compare it with anything else.
Can you just build your own?
Yes, if you build the wall properly: mineral wool, not foam or fibreglass; a foil vapour barrier taped with 120 C foil tape; a 15 to 20 mm air gap behind tongue-and-groove boards fixed without glue; and a ceiling insulated deeper than the walls.
The heater is not a DIY job. It needs a 240 V circuit of its own, wired by a licensed electrician, and an electrical permit almost everywhere. A larger outdoor build may need a building permit as well.
Count your time. A kit arrives cut and numbered. A scratch build means framing, insulating, foiling and cladding a small room to a standard most sheds are never held to.
How to decide.
Build it yourself if you enjoy the work, can get the wall right, and the sauna is a project in itself.
Buy a kit if you want it fast and a standard size fits. Ask for the wall spec before you pay.
Have one specified to your room if it is going into a house, has to fit an odd space, or is part of a larger build. That is where a sauna supplied as numbered panels with a layout drawing, assembled by your builder, makes sense.
Common questions.
- Is it cheaper to build or buy a sauna?
- It depends on what you count. Outdoor sauna kits with a heater were listed from $4,499 to $15,299 in August 2026. A DIY build only saves money if the wall is built properly and you count your own time as free.
- Can you just build your own sauna?
- Yes, if you build the wall properly: mineral wool insulation, a foil vapour barrier taped with 120 C foil tape, an air gap behind the boards, and no glue in the hot room. The heater's 240 V circuit must be wired by a licensed electrician.
- What should I check before buying a sauna?
- What is in the wall: the R-value of the walls and ceiling, the type of insulation, whether there is a vapour barrier and what tape seals it, whether there is an air gap behind the boards, and whether any adhesive is used inside the hot room.
- How much does a KLAFS sauna cost?
- KLAFS publishes few prices. Its retractable S1 was listed at $44,900 to $51,900 at its US launch in July 2026, with installation extra. Its made-to-measure models are priced by quote.
Sources.
- Backyard Discovery Lennon outdoor cube sauna: price and published wall spec
- Redwood Outdoors: outdoor sauna prices
- Coldture: PRO outdoor sauna (US)
- Coldture: XTREME outdoor sauna (US)
- KLAFS: S1 US launch and pricing, press release, 7 July 2026
For general information only, not medical advice. Ask a clinician before starting regular sauna use.
Keep reading.
Have one specified to your room.
Send the room dimensions, ceiling height and the electrical supply. We come back with a spec and a package price, supplied as numbered panels for your builder.