The Cozy Heat series gives you handmade Estonian craftsmanship at prices that make sense. Built where wood-fired saunas are standard in every home—not a luxury product—these stoves deliver the mild, long-lasting heat that makes wood-fired sauna different from electric.
The lineup includes 10 models across two power outputs: the 12kW series (210-423 cubic feet) and 18kW series (317-635 cubic feet). Each model comes in five design variations—from the classic round Cozy to the sleek cylindrical SW to the open-grid Quattro—plus through-wall versions if you want to load firewood from outside your sauna room.
What makes these worth considering is 5mm stainless steel construction in critical areas, a three-stage combustion system that cuts wood use by 25-40%, and 265-353 pounds of rock capacity for real steam. You’re getting build quality that lasts without paying import-luxury pricing.
Here’s what you’re actually getting with these stoves:
5mm Stainless Steel Flame Cutter
The most stressed part of any wood-fired stove—the flame cutter that takes direct heat—is made from 5mm thick stainless steel, which means the critical component that determines longevity is built heavy-duty.
The Cozy 12 holds 265 lbs of rock, the Cozy 18 holds 353 lbs—enough thermal mass to create proper steam when you throw water and maintain heat after the fire dies down.
Every model can be ordered as a TW (through-wall) version, letting you load firewood from outside the sauna room or from a dressing room, which keeps bark and ash out of your sauna space.
73.9% efficiency on the Cozy 12, 81.3% on the Cozy 18, meaning most of the heat from your firewood goes into your sauna room instead of up the chimney.
Watch the fire without opening the door, which keeps heat in the sauna and lets you monitor burn status. Not only that, but it provides a nice ambient experience (with the non-thru-wall options).
The Cozy 12 needs 6.7″ side clearance and the Cozy 18 needs 9″ sides—tighter than budget stoves that radiate more heat, wider than ultra-premium insulated models, but workable in most sauna layouts.
Cozy Heat offers 10 distinct models across two power outputs. Here’s what differentiates each one:
Cozy 12
Cozy 18
Cozy 12 O
Cozy 18 O
Cozy 12 SW
Cozy 18 SW
Cozy 12 OG
Cozy 18 OG
Cozy 12 Quattro
Cozy 18 Quattro
Fuel Specifications
Clearances to Combustible Materials – Cozy 12:
Clearances to Combustible Materials – Cozy 18:
With Heat Shield (distances can be reduced):
Minimum Chimney Draft Required: 12 Pa Flue Pipe Diameter: 4.5″ (114mm) Minimum Chimney Cross-Section: 12.7 square inches Ventilation Opening Required: 16.5 square inches minimum
Regular Maintenance (Before Each Use):
Periodic Maintenance (Annually or Every 40 Uses):
Chimney & Flue:
When to Replace Stones:
All five designs (standard Cozy, O, SW, OG, Quattro) have identical heating performance and internal construction. The differences are purely aesthetic—how the outer frame presents the stones. Pick based on which look fits your sauna and what you want to spend.
The 12kW covers 210-423 cubic feet, the 18kW covers 317-635 cubic feet. If you’re between those ranges where they overlap, go with the 12kW for faster heat-up times and less wood consumption, or the 18kW if you have lots of glass, tile, or concrete surfaces that absorb heat. A 300 cubic foot sauna with standard wood walls fits the 12kW fine. The same sauna with a glass door and tile walls would benefit from the 18kW. When in doubt, calculate your sauna’s cubic footage and add 1.2 cubic feet for every square foot of non-insulated surface (glass, concrete, brick).
If you load too much wood or leave all air controls wide open for extended periods, the stove body can overheat to the point where the metal starts to glow red. This is called overfiring and it’s not covered by warranty because it causes permanent warping and shortened stove life. How to avoid it: stick to recommended wood loads (8 lbs per session), close the ash drawer to 2mm after the initial 15-minute heat-up, and don’t run multiple back-to-back full loads just because you can. If your firebox starts glowing, you’ve gone too far—immediately close all air controls and let it cool. A properly fired sauna stove never glows red.
No to both. These stoves are engineered specifically for split cordwood (logs) with the dimensions listed in the specs. Wood pellets burn too hot and concentrated. Coal, briquettes, and pellets will damage the stove and void the warranty. This is also not a space heater or fireplace—it’s designed for occasional sauna use (bathing a few times a week at most), not continuous 24/7 heating. The materials are built for intermittent high-heat cycles, not constant burning.
Cozy stoves work in barrel saunas with proper installation. The curved walls don’t affect operation. You’ll need to follow clearance requirements to combustible materials (6.7-9″ sides depending on model), which in a barrel means positioning the stove far enough from the curved wall. The TW (through-wall) version works well in barrel saunas because you can load wood from outside the barrel, but you’ll need to properly seal and insulate where the extension tube passes through the barrel wall. Main consideration: make sure your barrel has enough interior space to meet minimum clearances. A 6-foot diameter barrel provides adequate clearance; smaller barrels can get tight with the recommended safety distances.
We build saunas the way they should be built—with Finnish expertise and Minnesota craftsmanship. Our team doesn’t just sell saunas; we use them daily, understand their construction inside and out, and have helped over 250 families create their perfect sauna experience—whether through a fully custom done-for-you sauna, DIY sauna kit or a modular system.
Every sauna we build reflects decades of combined experience in woodworking, construction, and traditional sauna design. Our builders handle projects from compact home saunas to luxury custom installations, ensuring precise construction and authentic performance every time.
Before you invest, visit our showroom to experience authentic sauna heat. Feel the difference quality materials and proper construction make. Talk with specialists who understand löyly, ventilation, and the details that separate a great sauna from an expensive disappointment.
Our 50+ five-star reviews on Google come from customers who’ve experienced the difference professional guidance makes—from initial design through your first sauna session.
From first-time buyers navigating their options to Finnish families honoring tradition, our customers tell it best. Read what verified reviewers say about working with us. Read 50+ 5 star customer reviews on Google here.
Get authentic wood-fired sauna heat from Estonian-built stoves. Ready to order or have questions about which model fits your setup? Fill out the form below or call us at 612-505-9700.
Experience the difference quality makes at our Cokato sauna showroom, where you can see, touch, and even try our saunas before deciding.
Explore custom indoor, custom outdoor, and modular models to compare construction, feel the authentic heat, and experience different wood types—whether it’s the aromatic Western Red Cedar, clear Canadian Hemlock, traditional Nordic Spruce, or more.
Our sauna specialists are here to answer questions, explain the differences between modular and custom builds, and help you visualize how a sauna fits into your space and lifestyle. Many customers tell us their showroom visit completely changed their understanding of what they wanted—there’s no substitute for seeing and sitting in a sauna before you buy.
Visit us at 500 Cokato St W, Cokato, Minnesota. Our standard business hours are 8AM-5PM CST. View our Google Business Profile for updated and holiday hours, or call 612.505.9700 to schedule an appointment.
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