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Heat and cold for your home, without the guesswork.

ThermoVell helps you size a home sauna or cold plunge for your space.

Size my sauna Size a cold plunge
The sizing calculator

What size sauna do you need?

Room volume: 175 cu ft

Products that fit your numbers

List prices, checked October 2026.

Match the chiller to the tub

Most tubs: 80 to 120 gallons.
1/2 HP chiller
For a 100 gallon tub.

Cold plunges that fit

More products

Infrared saunas

Medical Saunas

Medical 3

Infrared sauna · 1 to 2 people
Around $3,449
Check price
Sun Home Saunas

Equinox 2-Person

Infrared sauna · 2 people
Around $6,099
Check price
Medical Saunas

Medical 6

Infrared sauna · 3 people
Around $9,399
Check price
Sun Home Saunas

Luminar 2-Person

Infrared sauna · 2 people · outdoor
Around $10,999
Check price
Medical Saunas

Medical 8

Infrared sauna · 3 to 4 people
Up to $15,899
Check price

Traditional saunas

Redwood Outdoors

Barrel Sauna, 6 Person

Traditional barrel sauna · 6 people
Around $6,299
Check price
Redwood Outdoors

Barrel Sauna, 8 Person

Traditional barrel sauna · 8 people · outdoor
Around $6,899
Check price
Redwood Outdoors

Grove Outdoor Sauna

Traditional sauna · 8 to 10 people
From $6,299
Check price
Sun Home Saunas

Nova 3-Person

Traditional sauna · 3 people
Around $11,999
Check price
Plunge

The Sauna

Traditional sauna · full-size cabin
Around $15,848 CAD
Check price
Sun Home Saunas

Nova 6-Person

Traditional sauna · 6 people
Around $15,799
Check price

Cold plunges

Plunge

The Plunge (Tub Only)

Cold plunge tub · chiller sold separately
Around $5,284 CAD
Check price
Medical Saunas

Frozen Cold Plunge

Cold plunge · chiller included
$9,199 to $10,199
Check price
Sun Home Saunas

Cold Plunge Pro

Cold plunge · chiller-fed tub
Around $13,999
Check price
Redwood Outdoors

Alaskan Cold Plunge

Cold plunge · sold in sauna and plunge bundles
Bundles $12,199 to $14,999
Check price

More tools

Heat and electrical

Cost per sauna session

Electricity cost of one session.
$0.90
Per session, at full draw.
Energy used6.0 kWh
Three sessions a week$140 a year

Math: kW × hours × rate.

Electrical checker

The breaker and circuit a heater size needs.

Continuous load: draw plus 25 percent.

30A breaker
On a dedicated 240V circuit.
Heater draw at 240V18.8 A
With the 25% allowance23.4 A
120V plug-in possible?No, this size needs 240V

A licensed electrician confirms wire size and panel space.

Heat-up time estimator

How long a cold room takes to reach temperature.
About 51 minutes
Planning estimate, insulated indoor room.

Math: volume × rise ÷ (kW × 60). Outdoor runs longer.

Cold plunge and ownership

Cold plunge running cost

What the chiller costs to run each day.
$0.45 a day
About $13.43 a month.
Chiller draw373 W
Energy per day2.98 kWh

Math: 1 HP = 746 W.

Annual ownership cost estimator

Sessions, plunge, and supplies for the year.
$0 a year
Electricity and supplies only.
Sauna sessions$0
Cold plunge running$0
Filters and supplies$0

Math: sessions × 52, plus chiller × 365, plus supplies.

Brands we cover

Medical Saunas Sun Home Saunas Redwood Outdoors Plunge Golden Designs

About ThermoVell

ThermoVell is an independent sizing and research site for home saunas and cold plunges in the US and Canada.

We size from the room itself: volume, people, and circuit. Every result shows its math.

Contact: Richard Paul
hello@thermovell.com
647-832-1270

ThermoVell is independent. Links may earn a commission, at no extra cost to you.