At 150–200°F, materials don't behave the way they do in a living room. Heat raises vapor pressure, and coatings, glues and treated woods that sit quietly at room temperature start releasing what's in them — into air you're breathing deliberately and deeply.

There are certain chemicals which humans have not biologically evolved to come into contact with. These chemicals -- having direct and harmful physiological effect upon contact with our skin or introduction to our lungs, bloodstream, or other systems -- are toxicants, commonly referred to as "toxins." They are isolated or synthesized in extremely high concentrations in adhesives and other synthetic coatings and treatments.

So we leave them out. No veneers or laminates. No wood-mimicking plastic. No interior plywood or MDF. No chemically treated wood of any kind. Every board is sourced and milled in the U.S., and every sauna is built here.

That distinction is worth checking when you shop. "Built in the U.S.A." often describes assembly — the panels themselves can be manufactured and treated abroad, then put together here. Ask where the wood comes from, not just where the box went together.

We also build without adhesives. Where a detail would normally call for glue — a solid wood door, for instance — we work out a joinery solution instead. If a build ever does need an adhesive, it's zero-VOC, rated for sustained high heat, used sparingly, and you'll hear about it from us before we do it.

What's left is the thing itself: the scent of hot cedar, clear air, heat with nothing in it.