Backyard saunas: costs, permits and how to plan one

Updated October 27, 2026

Barrel, cabin or something custom

• Barrel saunas are round, built from staves held together with steel bands. They're a popular backyard kit and look the part, though headroom is tighter at the edges.
• Cabin or cube saunas have flat walls and a roof. They fit more people for the footprint, are easier to add windows, a changing room or a porch to, and suit a modern yard.
• Custom builds cost more but can match your house, fit a slope or tight corner, or include a shower and changing area. A custom two- to four-person cedar sauna with an electric heater runs around $7,000 to $8,000 installed.¹

Electric or wood-fired

Heater and running costs: Fixr.¹ If you live somewhere with burn bans or wood-smoke rules, check them before choosing wood.

The foundation

A sauna is heavy and has to sit level, or doors bind and barrel staves gap. Common bases are a poured concrete pad, pavers on compacted gravel, or a timber deck or frame. Whatever you pick, keep the wood off wet ground and make sure water drains away, both from rain and from the water you'll splash on the stones. Follow the kit maker's foundation instructions; many specify exactly what they'll accept under their warranty.

Getting power out there

A traditional electric heater needs its own 240-volt circuit, wired by a licensed electrician. Fixr puts an electrician adding a 220/240-volt circuit at $500 to $800.¹ For a backyard sauna the bigger cost is often the distance: the cable has to be buried or run in conduit from your panel, and longer runs need heavier wire. Get the electrician to look at your panel early, because some homes need a subpanel or a service upgrade to fit a sauna heater.

Permits

Rules are local, but most U.S. cities start from the International Residential Code. Its section R105.2 exempts "one-story detached accessory structures, provided that the floor area does not exceed 200 square feet" from needing a building permit.² Two catches:

• Many cities use a lower limit. Aurora, Texas, for example, requires a building permit for residential accessory structures larger than 120 square feet.³
• Wiring usually needs a permit regardless. Aurora's rule is typical: "Any electrical, mechanical, or plumbing work associated with accessory structures also requires a permit regardless of size."³

Zoning rules such as setbacks from property lines still apply even when no permit is needed, and HOAs often have their own rules. Before you order a kit, call your city or county building department and ask:

1. Does a sauna of this size need a building permit?
2. Does the electrical work need a permit and inspection?
3. What setbacks apply from the property line and the house?
4. For wood-fired: are there rules on wood stoves or chimneys in outbuildings?

Upkeep

Outdoor saunas weather. Plan to treat the exterior wood: Fixr lists outdoor wood stain at about $29 a gallon and wood preservative at $30 to $45 a gallon.¹ Leave the interior wood untreated. Check the roof, door seals and barrel bands each season, and let the sauna dry out with the door or vent open after each use.

DIY or hire a builder

A prefab four-person kit you assemble yourself costs about $2,640 to $4,790, compared with about $4,000 to $6,000 professionally installed.¹ If you're comfortable with a multi-day carpentry project and can prepare a level base, a kit is very doable. Hire a builder for a custom design, a difficult site, or if you want one company to handle the base, the build and the electrician. For a full cost breakdown, seehow much a home sauna costs.

Find backyard sauna builders in Austin, Chicago, Dallas, Los Angeles, Phoenix, San Diego and Seattle, or see all cities.

Frequently asked questions

How much does a backyard sauna cost?

Fixr puts outdoor saunas at $3,000 to $6,000. A prefab four-person kit you assemble yourself runs about $2,640 to $4,790, and a professionally installed prefab about $4,000 to $6,000. Add the cost of a level base and, for an electric heater, a 240-volt circuit run out to the sauna.

Do I need a permit for a backyard sauna?

Often, at least for the wiring. The model International Residential Code exempts one-story detached accessory structures up to 200 square feet from a building permit, but many cities set a lower limit, and electrical work usually needs its own permit at any size. Aurora, Texas, for example, requires a building permit above 120 square feet and an electrical permit regardless of size. Check with your local building department.

Is a wood-fired or electric backyard sauna better?

Electric is simpler day to day: set a timer or thermostat and it heats itself, but it needs a dedicated 240-volt circuit. Wood-fired needs no circuit and works far from the house, but you tend the fire, store firewood and need a chimney with the clearances in the stove maker’s instructions. Fixr estimates $25 to $30 a month to run an electric sauna and $20 to $40 for wood-burning, including wood.

Can I build a backyard sauna myself?

Many people assemble a prefab kit themselves; it’s a real carpentry project, so read the kit’s instructions before you buy. The electrical connection for an electric heater should be done by a licensed electrician, and in most places it needs a permit and an inspection.