Choose your type honestly
Wood-fired gives the deepest, most traditional heat and needs no electrical service — but demands fire clearances, insurance conversations and half an hour of patience. Electric is the workhorse of home and commercial saunas: push a button, precise control. Infrared cabins are a different product — pleasant radiant warmth at 45–60 °C, but no löyly, no steam, and the landmark Finnish studies were done in traditional hot rooms, not infrared. Steam rooms (100% humidity, ~45 °C) are a spa amenity, not a sauna. Mobile saunas on trailers — my own specialty — solve zoning and let a hospitality business test wellness revenue before committing to a building.
Ventilation: the detail that separates good from bad
The most common flaw I see in North American builds. A sauna is not a sealed box: each bather needs roughly 10–12 litres of fresh air per second to keep CO₂ below ~700 ppm — stale air is why people "can't last ten minutes" in bad saunas. Finland's VTT research institute has recommended mechanical downdraft ventilation since 1992: fresh air enters above the heater, rides the convection loop past the bathers, and is mechanically exhausted below the foot bench. Wood stoves largely ventilate themselves through combustion; electric heaters do not — they need the fan.
The other classic mistakes
Benches too low (your feet should sit above the stones — heat stratifies, and sitting in the cold layer wastes the stove); doors and windows that leak steam; no vapour barrier behind the boards; heaters undersized for the room volume; and "we'll figure out the changing area later" (you won't — plan the cool-down, shower and rest space with the same care as the hot room).
What it costs
Realistic Canadian ranges: a self-built backyard frame sauna from ~$8–15k in materials; a contractor build $25–60k+; a commercial-grade facility with showers, rest area and code compliance is a different category entirely — which is exactly the feasibility conversation I run with clients before any money moves. You can see one of my own builds — plan, 3D model, framing, opening day — on the About page.
