What is the best wood for a sauna?

Western Red Cedar is considered the best. It resists rot, stays cool to the touch, and releases a pleasant aroma. Basswood and aspen are good bench alternatives.

How much does a DIY sauna cost?

A DIY sauna typically costs $3,000 to $6,000 including heater, cedar, insulation, and electrical. Roughly half the cost of professional installation.

Most jurisdictions require an electrical permit for the heater circuit at minimum. Outdoor saunas may also need a building permit.

advanced

5-7 days

$3,000 - $6,000

How to Build a Sauna: Complete DIY Home Sauna Guide (2026)

Prepared by Lumberama's Building Projects Team

|Last updated May 26, 2026|Sources & methodology

Building your own sauna brings the luxury of a spa experience right to your home at a fraction of the cost of a commercial installation. Whether you choose an indoor conversion or an outdoor standalone building, the construction principles are the same: proper insulation, a continuous vapor barrier, and aromatic wood lining.

Key Takeaways

Building your own sauna brings the luxury of a spa experience right to your home at a fraction of the cost of a commercial installation.
Whether you choose an indoor conversion or an outdoor standalone building, the construction principles are the same: proper insulation, a continuous vapor barrier, and aromatic wood lining.
Never apply stain, paint, or polyurethane to interior sauna wood since finishes release toxic fumes at high temperatures.
Western Red Cedar is the gold standard because it resists rot and stays cool to the touch.
Keep ceiling height at 7 feet to reduce heating volume.

Tools Needed

framing nailer, circular saw, miter saw, drill/driver, staple gun, tape measure, level, utility knife, wire strippers, caulking gun, sandpaper

Materials List

2x4 or 2x6 wall framing, R-13 or R-19 fiberglass insulation, aluminum vapor barrier, 1x4 or T&G cedar wall and ceiling boards, cedar 2x4 bench framing, 1x4 cedar bench slats, sauna heater (electric or wood), sauna stones, sauna door (tempered glass), vent grilles, high-temperature electrical wire, GFCI breaker

Step-by-Step Instructions

Plan Size and Location

Size for 2-4 people (6x8 feet works well). For indoor conversions, choose a spot near plumbing. For outdoor, pour a concrete pad.

Frame the Walls and Ceiling

Frame with 2x4 or 2x6 studs at 16 inches on center. Ceiling at 7 feet. Include door opening and vent locations.

Run Electrical

Hire a licensed electrician for the dedicated 240V circuit. Install high-temperature wiring inside the sauna.

Insulate and Install Vapor Barrier

Fill cavities with fiberglass insulation. Staple aluminum foil vapor barrier over insulation with all seams taped.

Install Cedar Lining

Nail 1x4 tongue-and-groove cedar horizontally to walls and ceiling. Leave 1/2-inch gap at floor for air circulation.

Build the Benches

Build upper bench at 36-38 inches and lower bench at 18 inches using cedar framing and 1x4 slats spaced 1/2 inch apart.

Install Heater, Door, and Ventilation

Mount sauna heater per manufacturer specs. Install outward-swinging sauna door. Add lower intake vent and upper exhaust vent.

Add Finishing Touches

Install sauna-rated light fixture, thermometer, hygrometer, bucket and ladle, and duckboard floor panels.

Recommended Species

Western Red Cedar (walls, ceiling, benches), Basswood or Aspen (alternative bench material), Hemlock

Recommended Sizes

2x4 or 2x6 framing, 1x4 T&G cedar wall boards, 2x4 bench framing, 1x4 bench slats

Pro Tips

Never apply stain, paint, or polyurethane to interior sauna wood since finishes release toxic fumes at high temperatures. Western Red Cedar is the gold standard because it resists rot and stays cool to the touch. Keep ceiling height at 7 feet to reduce heating volume. Always hire a licensed electrician for the heater circuit.

Frequently Asked Questions

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