Sauna Building Basics

What type of sauna should I purchase or build?

There are 3 main types of saunas 1) Kit that is assembled on site 2) Prefabricated sauna delivered to site in finished condition 3) Custom sauna built from scratch on site. All three types of saunas have pros and cons. Saunas kits (#1), including barrel saunas, can be relatively inexpensive and delivered quickly but have significant limitations. Barrel saunas suffer from poor ventilation due to their round shape, which creates dead air zones that prevent proper air circulation. They typically have thin walls (usually 1.5" thick) compared to the 3.5" or thicker walls in quality custom builds, and they often lack proper vapor barriers essential for moisture management. Kits in general frequently use inferior materials and skip critical design elements like mechanical ventilation systems and proper stone mass for stable heat distribution. Prefabricated saunas (#2) can be produced with high quality materials and designs but often come with a relatively high price tag. Customers can explore options 1 and 2 but our company recommends option 3 and provides resources to help people achieve a high quality custom built sauna.

Who will build my sauna?

If you are handy and have access to basic power tools, you can build your own custom sauna! Alternatively, you can partner with a local builder and give them the guidance and design instructions to construct a sauna for you.

What will it cost?

Costs can vary depending on size, selected materials, and whether you choose to build it yourself or hire a builder. A 2-6 person sauna constructed by the home owner can range from $4,000-8,000 or $8,000-$20,000 if you hire out the work.

Where should I build it?

If you have the space, we recommend building your sauna outdoors where there is access to natural light and fresh air. You may also choose to build it indoors if you do not have a suitable outdoor space.

Wood or electric stove?

This is a personal preference but a few factors will determine which is the most cost effective or logical. If you already have a wood source or use a wood stove for your house a wood stove might make sense. Also, if you don't have space on your home electrical panel for a 40 amp breaker or you want to build the sauna very far away from your panel, electrical might not be advisable. If you have a spare 40 amp breaker on your panel and want the convenience of heating up your sauna with the click of a button, then electrical may be the right choice.

Where do I get the materials?

99% of materials can be purchased from a big box hardware store (like Home Depot or Lowes) and amazon. Your stove should be purchased online from one of many different distributors.

What type of materials should I use?

You should use standard shed building materials to build the sauna structure. For the inside you should use durable, moisture resistant types of wood and tile. Inside your sauna you want to avoid all types of chemical materials (like plastics, glues, calks) that will offgas toxic fumes when heated to high temperatures.

How long will it take to build?

If you're building the structure on your own, you can complete the sauna in 80-100 hours. If you hire a builder or have a crew, you may be able to finish it in 40-60 hours.

Can I use an existing building (E.g shed)?

Yes but there are a couple important requirements. Your existing structure should have walls that can be well insulated (E.g 2x4 studs) and the interior ceilings should be at least 7 feet tall to allow for tall interior benches.

How big should it be?

The structure should be somewhere between 4x6 ft (minimum) and update to 12x12 for a very large sauna. We recommend an 8x8 ft structure which allows efficient use of materials and allows space for 2 adults to lay down or 4-6 people to sit comfortably in the hot space (the top bench). A key design principle is maintaining at least 3 cubic meters (roughly 106 cubic feet) of sauna volume per person using it simultaneously. This minimum volume ensures proper air quality and even heat distribution throughout the sauna chamber.

What are some important design decisions?

Size and placement of windows, whether to install a drain, lighting, ventilation, and place to cool off outside (E.g. porch, roof overhang, shower, coldplunge). Several critical design elements deserve special attention: mechanical downdraft ventilation is essential for electric saunas to ensure fresh air circulation and remove stale air; proper stone mass is vital and should be calculated at 6-12 kg per cubic meter of room volume to function as a thermal battery that stores and releases heat gradually; and CO₂ monitoring helps maintain healthy air quality during use.

How hot will it get?

A well designed, insulated, high quality sauna should reach 160-200 F degrees within one hour of use. Compared to sauna kits, these types of saunas should also maintain high temperatures without the need for a constantly running stove. The key to this stability is proper stone mass. In a well-designed sauna, the stones act as thermal batteries, absorbing and storing heat from the stove while slowly releasing it back into the room. This gradual heat release maintains stable temperatures throughout your session, rather than experiencing temperature swings from the heating element cycling on and off repeatedly.