Electric Work is Best Performed by an Electrician
Plenty of home owners do their own electrical work. Electrical preparation involves reviewing the electrical capacity of your service panel for available amps. For example 4×6 sauna room uses: 6kW sauna heater / 240V / 30 amp breaker / 10 gauge wire. Run electrical wire planning for the heater, lights, switch and external controls (optional).
Electric saunas require a dedicated breaker and circuit and electric work. Safety first!
Most home saunas require 4.5kW, 6kW or an 8kW sauna heater unless of course, you prefer wood-fired all-natural, then NO you wouldn’t any electricity necessarily. Though you might still want a light bulb, but lanterns work was well or the flash light on your phone. Wood-fired saunas in the city may sometimes encounter burn ban days, so consider your options.
Typically, then sauna installations will require a dedicated 240 volt, 30 or 40 amp GFI-protected circuit. If you pull an electrical permit, it covers the sauna heater, light and switch and possibly a wall-mounted control panel, etc. Commercial saunas often have two 40 amp circuits (240 V).
If you’re renovating a room and constructing a sauna in your home, and you do your own electrical permit. Then when you sell your home, you’ve covered your responsibility when you declare on Form 17 any work that was done without permits.
Structural permits are usually NOT required
Commonly, an outdoor sauna and structures of 120 sq. ft. or less do not require permits (in the U.S.). Some counties allow larger structures of up to 200 sq. ft. without permits. You may run into some problems if you put your sauna right on the property line you share with a neighbor, a parking strip or an access easement.