Alder & Rime
An evidence-based sauna and cold-plunge planning site, written and run by one person — every heater spec, circuit figure and cold-exposure claim traced back to where it actually came from.
I’m Adam, and I write, research, fact-check and run the calculators on this site myself. There’s no editorial team, no roster of contributors, no research staff behind the byline — just one person doing the actual comparison shopping and reading the manufacturer spec sheets before telling you what a number means. That’s worth saying plainly, because “who wrote this and why should I trust it” is the right question to ask of any site that’s about to tell you what heater to buy or how to size a breaker.
Most sauna and cold-plunge buying advice online is a retailer’s product page wearing a blog headline, or a wellness site that treats hot and cold as the same kind of claim. They aren’t. This is genuinely two halves of one hobby — hot side and cold side — and they don’t share an evidence base or a shopping list. Alder & Rime keeps them separate: heater sizing and circuit planning on one side, chiller capacity and filtration on the other, and a shared protocols section where the two actually meet. The whole site is built for the planning stage — working out what you actually need and whether it fits your panel and your climate — not a concierge buying service.
How I work
Heater kW, amperage and circuit figures come from the manufacturer’s own nameplate rating or spec sheet — Harvia, HUUM and Thermory show up this way often — with the source named next to the number, not buried in a footnote. Anything that depends on local code — permits, GFCI requirements, breaker sizing — is flagged as varying by jurisdiction. It’s never stated as a national rule, because it isn’t one.
Cold exposure is where this matters most: the finding that cold-water immersion right after a strength session can blunt the muscle-building response is real, and it’s stated here rather than buried under generic “cold is good for recovery” copy. Sauna and cold-plunge claims are tiered separately for exactly this reason — the cold side defaults a tier more skeptical, because its evidence base is thinner.
If a spec is wrong or a calculator gives you a bad number, tell me through the contact page — it’s the fastest way to get it fixed. I’ll correct it and say what changed, rather than editing it away without a note.
The most useful sentence on this site is often the one that talks you out of buying something — a barrel sauna that won’t survive your climate, a chiller sized for a tub twice as large as the one you’re actually planning. That’s the point of the site, not a failure of it.
How this is paid for
Alder & Rime is reader-funded. My intention is for some of the links here to earn a commission when you buy through them — the retailer pays that out of their own margin, so you pay the exact same price either way. Nobody pays me for a review, for a placement, or for a kind word, and no merchant sees an article before it goes live.
As of today, no affiliate programme has approved this site — it’s too new to have applied yet. When the first one does, that retailer is named on the disclosure page the day it happens, before a single link to it is tagged.
You also won’t find an exact price next to a product name anywhere on this site. Pricing in this category moves too often for a figure I print once to stay true, so the site bands price by tier instead and sends you to the retailer for today’s number.
What this site won't do
I’m not a licensed electrician, a sauna installer or a clinician, and nothing on this site replaces any of the three. The circuit planner gets you to a breaker size and wire gauge worth bringing to a licensed electrician — it doesn’t replace the permit drawing your AHJ (authority having jurisdiction) actually requires, and that office has the final word, not this site.
Health content here is informational, not medical advice, even where a claim is well-supported. Talk to a clinician who knows your history before starting heat or cold exposure, especially with a cardiovascular condition, during pregnancy, or on medication that affects blood pressure or heat regulation.
And I don’t try to cover every accessory in the category. If something isn’t a planning decision — shape and material tradeoffs, breaker sizing, filtration cadence, chiller capacity — it’s probably not here.