Rime forms on alder. Plan for both sides.

The heater size and the breaker it needs, worked out before you buy either one.

Every figure here is checked against a source we name. Where the trade disagrees — like a heater's glass-load constant — you see every published number, not a house guess. Prices are banded, never quoted.

Open the calculators Start with the guides

Start with your build

All guides →
Sauna Types & Selection Traditional or infrared, barrel or cabin, indoors or out — the shape and heat-source decisions that come before anything else. 4 guides
Heaters & Electrical Heater kW sizing, electric vs wood vs gas, the 240V circuit and wire gauge it needs, GFCI, and what it actually costs to run. 6 guides
Build & Installation Foundation and pad prep, ventilation, vapor barrier and insulation, and the wood species that actually belongs inside a hot room. 5 guides
Cold Plunge & Contrast Chiller sizing in HP and BTU, and the filtration and sanitation choice — ozone, UV, or a filter — that keeps the water usable. 2 guides
Evidence & Safety What the evidence actually shows on cold-water recovery, and who shouldn't be doing either of these without a clinician's sign-off first. 2 guides

Why the numbers here are different

Alder & Rime is a planning site for sauna and cold-plunge builds. Every figure carries the source it came from, and where the trade itself hasn't settled on one number, you see the disagreement instead of a single confident answer.

A source on every figure

Room volume, glass load, breaker size — each one is checked against a manufacturer spec sheet or a named retailer's own published numbers, not repeated from another blog.

Disputes shown, not smoothed over

Some numbers this trade uses don't agree with each other yet. The heater-sizing tool is the clearest example: five different published glass-load constants, shown side by side with who publishes each one, instead of one quiet house guess standing in for consensus.

Bands, not a number that's already wrong

Prices move on their own schedule — sale events, freight surcharges, dealer terms that cap what can be advertised. We publish a tier and send you to the retailer for today's real number, rather than print a figure that's stale within weeks.

"You don't need this yet"

The most useful sentence on a build page is often the one that says your existing setup is fine. We write it whenever it's true, and it earns us nothing — which is rather the point.

Latest guides

All guides →
Evidence & SafetyCold Plunge Recovery EvidenceThe honest verdict: cold-water immersion reliably eases short-term muscle soreness and gives a brief lift to mood and alertness, but most of...
Evidence & SafetyCold Plunge MaintenanceMaintenance is a cadence, not a one-time task — and this house runs both hot and cold, so the cadence covers both...
Evidence & SafetySauna and Cold Plunge Session ProtocolsThere’s no single correct protocol for either modality — only sourced ranges, each labeled by how firm the evidence actually is. For...

Who this is for

Being specific about who this isn't for is more useful than pretending to cover everyone.

This is for you if
  • You're sizing or speccing a real build — a heater, a circuit, a chiller — not just browsing for photos of finished ones.
  • You want a source cited next to every figure, and the real disagreement shown when the trade hasn't settled one — not a single confident number standing in for consensus.
  • You're fine with a price band and a link to check today's number, because dealers limit what they're allowed to advertise and a printed figure goes stale within weeks.
This isn't the site for
  • "What's the best sauna?", full stop — no room dimensions, no glass, no plan yet. It's a different, better-served-elsewhere question.
  • An exact retail price quoted here for a named heater or tub. You'll get a tier and a "check current price" link instead.
  • Medical guidance on heat or cold-water exposure. Every guide says this plainly: informational, not medical advice — talk to a clinician who knows your history first.

And plainly: "you don't need this yet" is one of the more common answers on this site. That isn't a lost sale — it's the same discipline that keeps every sourced number here honest.