What does sauna installation cost, on top of the sauna?

A kit or a heater arrives with a sticker, and the sticker is for the box. Between the pallet and a sauna you can sit in are four more lines: the assembly, the electrical, the permit and the base. Our Bay Area cost guide covers what drives the price of a custom room; this one is about putting in something you have bought.

Prefab assembly, priced per model. We assemble any kit you bought, any brand, with site prep and hookup as needed. The price covers assembly; electrical work is quoted separately, and so is site prep. The assembly is the site check, leveling, the panels to the manufacturer's spec, the ventilation, the heater test and the walkthrough. Most are a single day; a larger or outdoor unit, or a longer power run, can push it to two. The prefab assembly page lists the steps.

Equipment installation, from $590. Installation labor only; the heater, control or accessory is billed separately. It covers sizing the heater to the room's volume, mounting it with the right stone load and guard clearances, the controls and the test-fire. If a tired heater has to be diagnosed before it is replaced, that is a service visit, from $390, covering the diagnostic visit and the first 1.5 hours on site.

Both are starting figures, not quotes. You have an exact written number after a site visit.

Every electric heater runs on its own dedicated 240-volt circuit, GFCI-protected, with a disconnect nearby. The running current is simple arithmetic: amps = kW x 1000 / 240, so a 4.5 kW heater draws about 19 amps and a 9 kW heater about 38. What that circuit costs to put in is decided by three things no brochure can tell you:

• The run. How far the heater is from your panel. A garage beside the panel is a short run; a cabin across the yard needs a trench, with the cable in conduit, buried to code depth, and the distance and what is in the way (paths, roots, hardscape) drive the labor.
• The panel. A 30-60 amp 240-volt circuit needs an open double-pole slot and spare capacity. Older Bay Area homes on 100-amp service, or with an EV charger or central air already on the panel, may need a subpanel or a service upgrade first. A load calculation answers it, and we run one at the free site visit.
• The inspection. GFCI protection and the disconnect are standard; what the inspector asks for on top is set by the code edition your city enforces.

That is why the electrical is quoted separately from the assembly price rather than folded in: the same kit on two streets can need two very different circuits. The 240V guide has the rest.

In nearly every Bay Area city a new 240-volt circuit needs an electrical permit and an inspection, kit or custom, even when a small detached structure skips a building permit. The fee is set by your city and itemized in your quote; it is usually a small part of the total, and the larger cost is doing the work so it passes. We file the permit and carry the inspection as part of the hookup. Whether the structure needs a building permit depends on its size, whether it is attached, and your city; the permit guide goes city by city.

Indoors, a level floor near the panel is the cheapest installation there is. Outdoors, the sauna needs something under it: a concrete slab, a compacted gravel pad, a deck rated for the weight of a loaded sauna and the people in it, or footings on a slope. We recommend the base after seeing the spot, and it is quoted separately from the assembly. Two more things move the day's cost: access, because the panels have to reach the spot, and drainage, because water that does not run away from the structure rots timber from below and heaves a poorly set pad. The site prep guide walks through each base.

Delivery is the seller's line, not ours, and kit shipping varies by brand. Ask whether it is curbside or placed, because carrying a pallet from the curb to the backyard is labor on assembly day. Buy the kit from our shop and the assembly is one conversation.

The other cost shows up later: most manufacturers require the unit to be assembled to spec and the electrical done by a licensed pro, and a DIY job or an unlicensed hookup is a common reason a warranty claim is denied.

Put them side by side on the same lines: assembly, circuit, permit, base, commissioning. When one bid comes in well under the others it is usually not the same scope; it is the same box with the hard parts left off. Ask who pulls the electrical permit, who runs the circuit, and who brings it to temperature before leaving. The fair comparison is a finished, permitted, working sauna against another one, not sticker against sticker.