
Finnmark Designs FD-3: a four person indoor infrared sauna with a wide bench
The Finnmark Designs FD-3 is a four person indoor infrared sauna. Full spectrum means it mixes two kinds of infrared heaters, carbon panels for gentle all over warmth and Spectrum Plus heaters for stronger direct heat. Red light lamps in the ceiling add a warm glow. The outside is thermo-aspen, which is aspen baked in a kiln so it will not warp or rot. The inside is Western Canadian cedar, a smooth wood that resists mold. Four people can sit on the wide bench across the back. A full glass door lets in light. It takes up about 71 by 45 inches of floor space, so plan for a spot in a basement, a home gym, or a large spare room.
It needs a 240 volt outlet on its own circuit, wired by a licensed electrician. The room warms to 170 degrees in about an hour. Inside you get a touchscreen control panel with Bluetooth and speakers, and adjustable feet for an uneven floor. It comes as a kit of finished panels that screw together. On the page you can add a waterproof cover, a four person vinyl seat cushion, a cedar backrest, a headrest, and wood wax or oil. Want a traditional stove and steam in the same room? See the Finnmark Designs FD-5 hybrid sauna. The Finnmark Designs FD-3 ships free from My Cozy Outdoors with No Sales Tax (except WY) and the full manufacturer warranty.
FAQ
Does the FD-3 plug into a regular outlet?
No. This four-person cabin runs on 240 V, 15 A, single phase with a NEMA 6-15P plug, so you need a 240 V receptacle on its own circuit; the product page and the linked manual both say to have an electrician install it. The manual also asks for a properly grounded outlet, no extension cords, and a GFCI in any potentially damp location.
How much room do I need for a four-person infrared sauna?
The cabin is 72 in wide, 46 in deep and 78 in tall on the outside, with a 67 x 41 x 70 in interior of about 111 cubic feet. Add the 3 inches of clearance the manual requires on the top and all sides, so about 78 x 52 in of floor under an 81 in ceiling. The glass door is 23.6 in wide. It is freestanding and should not be built into a structure.
How long does it take to heat up, and how hot does it get?
Maximum temperature is 170 F. The manual’s warm-up table lists 55 to 65 minutes for the 3-4 person model to reach that ceiling, and suggests waiting 15 to 20 minutes for a comfortable temperature before a session. Warm-up depends on the ambient temperature, airflow and placement, and the manual recommends two or three full-heat cycles on first use to burn off factory dust.
How heavy is it, and how does it arrive?
The assembled sauna weighs 488 lb; it ships at 536 lb on a 48 lb wooden pallet measuring about 36 x 78 in. Delivery is curbside by appointment, so plan on help to move the panels inside. Assembly follows the linked manual: bottom panel and feet, back and side panels, bench, front panel with glass door, then the top panel, which the manual says takes two people.
What accessories are included, and which are optional?
The Includes tab covers the complete panel kit, glass door, bench, infrared heater panels, Spectrum LED ceiling lights with red-light therapy, the LCD touchscreen controller with Bluetooth, 6 in HiFi speakers, power supply and hardware. The FD-3 waterproof cover, a 3-4 person marine vinyl cushion, cedar backrest, headrest and wood-care items are optional; they appear in the selectors on this page with their prices. See more infrared saunas here.
How often can I use it, and how long should a session be?
The manual suggests no more than three sessions a week for the first four weeks and daily use after six weeks if you wish. Sessions of at least 30 minutes give noticeable results, with 45 minutes advised for therapeutic use; start at a lower temperature and work up. Drink water before, during and after, and consult your physician first if you have a medical condition or are pregnant.
What does the warranty cover?
The Limited Warranty in the manual linked under the Manual tab covers the original residential purchaser: Spectrum Plus heaters for life; carbon heaters, craftsmanship, electrical components and audio components for 10 years; the lighting remote for 1 year; and commercial use for 5 years. It excludes broken glass, bulbs, weather damage and units placed outdoors without the cover, and freight for parts after 30 days is the customer’s.