A compact, owner-built 6x8 Finnish-style sauna that seats 4-5, with a Harvia Spirit 9kW WiFi heater and a three-vent mechanical ventilation system.
This is a 6x8 Finnish-style sauna we designed for a client in South Lake Tahoe who wanted to build it himself. The goal was a true hot, dry Finnish sauna — high heat, fast recovery, and clean air — in a compact footprint that still seats a group. We laid out three tiers of benches in a small L-shape so it comfortably fits 4-5 people, with the top bench up where the real heat sits. The heater is a Harvia Spirit 9kW with WiFi app control, so you can start it from your phone and have it up to temperature before you walk out back — which matters in a Tahoe winter. The piece we spent the most time on was ventilation. A lot of small saunas get built with a single vent, or none, and end up with cold feet, stale air, and heat that stacks at the ceiling. This one runs a three-vent system with mechanical ventilation: fresh air in near the heater, a controlled exhaust, and a return that keeps the air turning over. The payoff is even heat from your feet to your head and air that stays fresh through a long session. We kept the windows small on purpose — just enough glass to let light in and frame the little ravine behind the property, without dumping heat the way a big picture window does. Redwood benches, western red cedar on the walls and ceiling, pine siding outside, and warm under-bench LED lighting so there are no fixtures up in the heat zone.
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“I had a great experience with Tahoe Sauna Company. They designed our outdoor home sauna and provided a detailed material list and cost estimate that I used to build my sauna. Thank you!”
This one was owner-built, so there's no contractor labor in the number. Materials came in around $6,000 — the Harvia Spirit heater, the mechanical ventilation, cedar and redwood, and the windows are where most of that goes. Your own material costs will vary with local prices and what you already have on hand.
Whether you're building it yourself or hiring it out, we design custom saunas around your footprint, climate, and how you actually want to use them — heater sizing, bench layout, and ventilation all planned before anyone picks up a saw.
Start the Design ProcessTahoe Sauna Company provides design and consulting services only. This sauna was built by the owner from our design, under a separate arrangement.
12 decisions that determine how well your sauna performs — insulation, bench height, heater sizing, ventilation, and more. Get them right before you build.
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