# Home Sauna and Steam Room Permits, Codes and Electrical Rules

The main electrical standards, permits and construction rules for home saunas, steam rooms and cold plunges in the US, Canada, the UK and Australia, with sources.

Updated 2026-10-29. Also on the [web page](https://privatewellnessrooms.fyi/guides/home-sauna-and-steam-room-permits-codes-and-electrical-rules).

This guide lists the main rules we could confirm from public sources. It is not legal advice. Your electrician and your local inspector make the final decision.

## The rule that applies everywhere

Follow the manufacturer's installation manual. It sets clearances, circuit size, cable type and ventilation.

## United States

- **Heater standard.** UL 875 covers electric dry-bath heaters (sauna heaters) rated 600 volts or less. The scope says they are installed in accordance with the National Electrical Code, NFPA 70. The equipment must have an automatic temperature control with a manual-reset limit control and a timer. UL 875 does not cover steam-bath heaters.
- **Circuit sizing.** Sauna Heater Supply, a retailer, says sauna heaters fall under NEC Article 424. It says the 125% continuous-load rule applies. Its example: a 6 kW heater draws about 25 amps at 240V, so the circuit sizing starts at about 31.25 amps.
- **GFCI.** Sauna Heater Supply says the NEC does not universally require GFCI protection on hard-wired heater circuits. Some heater manuals forbid it. Agree on this with your electrician before you choose a heater.
- **Permits.** Sauna Heater Supply says virtually every US jurisdiction requires a permit and inspection for a new high-amperage circuit.

## Canada

- **Ontario.** The Ontario Electrical Safety Code requires a notification of work to the ESA before electrical work starts. A Licensed Electrical Contractor files it for you.
- **Toronto.** RenoHouse, a contractor, says a basement sauna that adds partitions and a new circuit needs a City of Toronto building permit. It gives a 2026 minimum fee of $214.79 (CAD).

## United Kingdom

BS 7671 Section 703 covers rooms and cabins that contain sauna heaters. Elec-Mate summarises it as follows:

| Rule | Requirement |
|---|---|
| Zone 1 | The heater volume, out to 0.5 m from the heater surface |
| Zone 3 equipment | Must withstand at least 125°C |
| Zone 3 cable | Insulation and sheaths must withstand at least 170°C |
| RCD | 30 mA on all sauna circuits; not required on the heater unless the maker recommends it |
| Socket-outlets | Not permitted in the location that contains the heater |

Section 703 does not apply to prefabricated cabins that comply with a relevant equipment standard. Elec-Mate says a new circuit is notifiable under Part P in England and Wales. GOV.UK says that you do not need approval yourself if you use someone registered with a competent person scheme. Steam & Oak says most garden saunas fall under permitted development, so planning permission is usually not needed.

## Australia and New Zealand

AS/NZS 3000 (the Wiring Rules) has a clause on saunas, clause 6.5. NECA Victoria says it applies to rooms or enclosures with heating equipment for sauna use. Three zones apply, based on distance from the heater. Ask your electrician to show how the design meets it. In New South Wales, the NSW Government tells homeowners to check a contractor's licence on the Verify NSW website.

## Sauna construction

The Harvia KIP heater manual says:

- The air in the sauna room should change six times per hour.
- Walls and ceiling need insulation of at least R11.
- A paper-backed aluminium vapour barrier goes over the insulation, with the aluminium side facing into the room.
- A receptacle shall not be installed inside the sauna room.

## Steam rooms

- **Wiring.** The Mr. Steam generator manual says licensed electricians and plumbers must do the installation. It calls for a separate circuit breaker and a disconnect within sight of the generator, or one that can be locked open.
- **Surfaces.** Mr. Steam says walls and ceilings must be water-resistant and non-porous, such as tile or stone. Steam is not suitable for wood surfaces.
- **Vapour barrier.** Mr. Steam says to include a vapour barrier and/or waterproof material behind the surface. Laticrete recommends both a vapour barrier and a waterproofing membrane.
- **Slopes.** Laticrete says the ceiling must slope at least 2 inches per foot, citing the Tile Council of North America. The floor must slope ¼ inch per foot to the drain.

## Cold plunges

- **GFCI.** A Plunge manual says to plug the unit only into a GFCI outlet. It says not to remove or bypass the GFCI.
- **Dedicated circuit.** The Hydro Systems chiller guide calls for a dedicated 110-volt, 20-amp GFCI receptacle.
- **Barriers.** HomeGuide says most US cities require a barrier around pools that exceed a certain depth.

We did not confirm the rules for Ireland, the UAE, Switzerland, Singapore or Hong Kong. Use a locally licensed electrician and ask the local authority.

Compare builders, dealers and installers near you in our directory.

## Sources

- [UL Standards & Engagement: UL 875, Electric Dry-Bath Heaters](https://www.shopulstandards.com/ProductDetail.aspx?UniqueKey=46790) (10th edition, 8 July 2024; fetched 2026-10-29)
- [Sauna Heater Supply: Sauna electrical requirements](https://saunaheatersupply.com/blogs/sauna-heater-supply-school/sauna-electrical-requirements) (fetched 2026-10-29)
- [Electrical Safety Authority: Finding the right contractor](https://esasafe.com/compliance/finding-the-right-contractor/) (fetched 2026-10-29)
- [RenoHouse: Basement sauna installation Toronto, 2026 cost and permit guide](https://renohouse.ca/blog/basement-sauna-installation-toronto-2026) (fetched 2026-10-29)
- [Elec-Mate: Sauna electrical installation, BS 7671 Section 703](https://www.elec-mate.com/guides/sauna-electrical-installation) (fetched 2026-10-29)
- [GOV.UK: Building regulations approval](https://www.gov.uk/building-regulations-approval/electrical-installations) (fetched 2026-10-29)
- [Steam & Oak: Sauna installation UK](https://www.steamandoak.co.uk/blogs/news/sauna-installation-uk) (29 August 2026, fetched 2026-10-29)
- [NECA Victoria: AS/NZS 3000 damp situations explained](https://www.necavic.asn.au/site/site/News/latest-News/2025/August/AS-NZS_3000_Damp_Situations_Explained.aspx) (August 2025, fetched 2026-10-29)
- [NSW Government: Step-by-step guide to choosing the right tradesperson or builder](https://www.nsw.gov.au/housing-and-construction/building-or-renovating-a-home/preparing/step-by-step-guide-to-choosing-right-tradesperson-or-builder) (fetched 2026-10-29)
- [Harvia: KIP heater owner's and operator's manual](https://harviaheater.com/wp-content/uploads/2024/02/kip.pdf) (fetched 2026-10-29)
- [Mr. Steam: Steambath generator installation, operation and maintenance manual](https://pim.mrsteam.com/Resources/Entities/Mrsteam/Documents/6446cb4f-5f9a-433c-9c0a-111dab242cb3.pdf) (fetched 2026-10-29)
- [Mr. Steam: Virtual technical support center](https://www.mrsteam.com/virtual-tech/) (fetched 2026-10-29)
- [Laticrete: TDS 172, steam rooms and steam showers](https://cdn-global.laticrete.com/-/media/project/laticrete-international/shared/files/support-and-downloads/technical-datasheets/tds172.ashx?la=en) (fetched 2026-10-29)
- [Plunge: Cold plunge manual (copy hosted by Wellness Shop)](https://www.wellnessshop.ca/wp-content/uploads/2025/02/Cold-Plunge-Manual.pdf) (fetched 2026-10-29)
- [Hydro Systems: Cold plunge chiller installation guide](https://hydrosystem.com/wp-content/uploads/2024/04/HS-Cold-Plunge-Install-Guide-Jan-2024.pdf) (January 2024, fetched 2026-10-29)
- [HomeGuide: How much does a plunge pool cost?](https://homeguide.com/costs/plunge-pool-cost) (fetched 2026-10-29)

## Questions

### Does a home sauna need its own circuit?

Usually, yes. Sauna Heater Supply says most traditional electric heaters need a dedicated 240V circuit. Small plug-in infrared units can use 120V, but the circuit must still serve the heater only. Always follow the heater manual.

### Does a sauna heater need RCD or GFCI protection?

It depends on the country and the heater. Under BS 7671 Section 703, all sauna circuits need 30 mA RCD protection, but the heater itself does not unless the maker recommends it. The Harvia KIP manual says that heater must not connect to a GFI breaker. Agree the design with your electrician before you buy.

### Do I need a permit for a home sauna?

Often, yes, for the electrical work. In England and Wales, a new circuit is notifiable under Part P. In Ontario, the electrical work must be notified to the ESA before it starts. Check with your local building department.