How to Use an Outdoor Sauna in Winter: Wood-Burning Stoves vs. Electric Heaters

Winter might be the best time to enjoy your outdoor sauna. There's something special about stepping into a warm sauna while snow covers the backyard and cold air surrounds you.

But if you're new to winter sauna bathing, you probably have a few questions. Can an outdoor sauna handle freezing temperatures? Is a wood-burning stove better than an electric heater? And how do you keep everything running smoothly when temperatures drop?

The good news is that you can enjoy an outdoor sauna in winter with the right equipment and a little preparation.

Let's walk through your options and help you find the best setup for your backyard.

Yes, you can use an outdoor sauna in winter, provided it's designed for outdoor conditions and installed and operated correctly.

Traditional outdoor saunas are built to handle changing temperatures. A properly sized heater can bring the sauna room up to its intended operating temperature even when it's freezing outside.

However, winter conditions require a few extra precautions.

• Safe access: Keep walkways, stairs, and entrances clear of snow and ice.
• Proper ventilation: Never block the ventilation openings required by your sauna or heater manufacturer.
• Heater clearances: Maintain the required distance between your heater and combustible materials.
• Electrical safety: Make sure electric heaters and controls are installed according to their manuals and applicable electrical codes.
• Chimney safety: Wood-burning stoves need an approved chimney system and proper installation.

Always follow the manufacturer's instructions for your specific sauna and heater.

A wood burning sauna stove heats your sauna by burning firewood inside a specially designed firebox. The stove warms the sauna stones, which release heat into the room.

Wood-burning stoves are a popular choice for outdoor saunas because they create a traditional sauna experience without requiring electricity for the stove itself.

Wood-burning stoves require more attention than electric heaters, especially during winter.

• Firewood storage: You'll need a supply of properly seasoned, dry firewood.
• Manual lighting: Starting a fire and reaching your preferred temperature takes planning.
• Ash removal: The firebox and ash compartment need regular maintenance.
• Chimney installation: A suitable chimney system is essential for safely venting combustion gases.
• Local regulations: Check applicable fire codes, smoke restrictions, permits, and installation requirements.

For a more complete setup, browse our wood sauna stove packages and sauna chimneys.

Wood-burning sauna stoves generally come in two feeding configurations.

Interior-feed stoves have a firebox door inside the sauna. You add wood directly from the sauna room, making it convenient to maintain the fire during a session.

Through-wall-feed stoves have a firebox opening that extends through an approved wall assembly. This allows you to load firewood from an adjacent space or, when specifically designed and approved for it, from outside.

Through-wall models can help keep firewood debris out of the sauna room, but installation requires careful attention to wall construction, clearances, and the manufacturer's approved components.

Neither configuration is automatically better. Your sauna layout, installation requirements, and personal preferences should guide your choice.

An electric sauna heater uses electrical heating elements to warm sauna stones and heat the room. Once installed, it offers a straightforward way to enjoy your outdoor sauna throughout winter.

For homeowners who prefer convenience, electric heating is often the easier option.

Smart electric sauna heaters can make winter sauna use more convenient by offering compatible app-based controls, scheduling, or remote-start features.

Imagine getting home on a snowy evening and having your sauna ready after an approved preheating cycle.

However, remote operation isn't available on every electric heater. Some systems require additional equipment, safety sensors, specific controls, or confirmation that the sauna is safe to start.

Never bypass safety interlocks or remotely operate a heater unless its manufacturer expressly permits that setup.

Explore our smart electric sauna heaters if convenience is a priority.

The best choice depends on whether you value the traditional wood-fire experience or the convenience of electric heating.

Here's how the two options compare for winter sauna use.

Wood-Burning Stove at a Glance

• Heat-up time: Varies with the fire, weather, and sauna size
• Power needed: No electricity for a non-electric stove
• Works during an outage: Yes, if the setup is fully non-electric
• Remote start: No
• Upkeep: Firewood, ashes, and chimney maintenance
• Best for: A traditional experience and off-grid properties

Electric Heater at a Glance

• Heat-up time: Varies with heater output and sauna size
• Power needed: Electrical supply required
• Works during an outage: Generally no
• Remote start: Available on compatible models
• Upkeep: Stone inspection and periodic maintenance
• Best for: Convenience and regular use

Both options can heat an outdoor sauna effectively in cold weather when properly sized and installed.

Proper sauna heater sizing starts with your sauna's interior volume, measured in cubic feet.

A heater that's too small may struggle to reach your preferred temperature, especially during cold weather. An oversized heater can also create performance and safety concerns, so choosing the largest available heater isn't the answer.

Step 1: Calculate Your Sauna's Volume

Multiply the interior length, width, and height in feet.

Length × Width × Height = Cubic Feet

For example, a sauna measuring 6 feet long, 6 feet wide, and 7 feet high has an interior volume of:

6 × 6 × 7 = 252 cubic feet

This gives you a starting point for selecting a heater.

Step 2: Account for Glass and Other Surfaces

Large glass doors, windows, and uninsulated surfaces can increase the heating demand.

Some manufacturers specify an additional equivalent room volume for each square foot of glass, stone, or other non-insulated surfaces.

Use the calculation provided by your heater manufacturer rather than applying a universal adjustment.

Step 3: Consider Your Winter Climate

In regions with long, harsh winters, heater performance deserves extra attention.

A heater near the lower end of its approved room-volume range may take longer to warm the sauna in freezing conditions.

When appropriate, choosing a model with additional capacity within the manufacturer's approved sizing range may improve warm-up performance.

Also consider insulation, door seals, ventilation, and the sauna's construction. A larger heater won't fix significant heat loss.

A few simple habits can make your winter sauna sessions easier, safer, and more enjoyable.

1. Allow Extra Warm-Up Time

Cold outdoor temperatures can increase the time required to heat your sauna.

Start earlier than usual, monitor the room temperature, and allow the heater to reach its normal operating conditions before entering.

2. Clear Snow and Ice

Keep the sauna entrance, stairs, and surrounding walkways clear.

Remove snow from areas where it could obstruct required ventilation or interfere with safe access. Never climb onto a slippery roof to remove snow.

3. Use Dry Firewood

For wood-burning stoves, use properly seasoned firewood that meets the stove manufacturer's recommendations.

Wet wood burns less efficiently and can increase smoke and creosote buildup.

4. Install Appropriate Carbon Monoxide Protection

Wood-burning equipment produces combustion gases, including carbon monoxide.

Install and maintain carbon monoxide alarms in appropriate locations according to applicable codes, alarm instructions, and professional installation guidance. A carbon monoxide alarm does not replace correct chimney installation, ventilation, or maintenance.

See the CDC's carbon monoxide prevention guidance.

5. Protect Your Sauna's Wood

Snow, rain, and repeated moisture exposure can affect exterior wood over time.

Follow the sauna manufacturer's recommendations for exterior treatments, drainage, ventilation, and seasonal maintenance. Avoid applying unapproved finishes to interior surfaces.

6. Stay Hydrated

Sauna bathing causes sweating, so it's important to replace fluids.

Drink water before and after your session, take breaks as needed, and leave the sauna if you feel dizzy or unwell. Harvard Health's Saunas and your health page discusses hydration and other sauna precautions.

7. Avoid Alcohol

Skip alcohol before and during sauna sessions.

Alcohol can increase the risks associated with heat exposure, including impaired judgment and dehydration. If you have a medical condition or take medications that affect heat tolerance or blood pressure, consult your healthcare professional before using a sauna.

Research suggests that regular sauna bathing may be associated with certain cardiovascular health benefits, although it doesn't establish that sauna use directly causes those outcomes.

A widely cited 2015 study published in JAMA Internal Medicine followed 2,315 middle-aged Finnish men. Researchers found that more frequent sauna bathing was associated with a lower risk of fatal cardiovascular events and all-cause mortality during follow-up.

Read the study: Association Between
Sauna Bathing and Fatal Cardiovascular and All-Cause Mortality Events.

A 2018 review in Mayo Clinic Proceedings also examined potential associations between sauna bathing and cardiovascular and other health outcomes.

Read the review: Cardiovascular
and Other Health Benefits of Sauna Bathing.

It's important to understand the limitations. Much of the available research is observational, meaning it identifies associations rather than proving cause and effect. Findings from Finnish sauna users may not apply equally to everyone.

If you have heart disease, unstable blood pressure, or another health condition, talk with your doctor before beginning a sauna routine.

Both wood-burning stoves and electric heaters can make an outdoor sauna a wonderful part of your winter routine.

If you enjoy tending a fire, want a traditional experience, or need a non-electric heating option, a wood-burning sauna stove may be your best fit.

If you prefer simple controls, less maintenance, and the possibility of scheduled heating, an electric sauna heater may be the better choice.

Whichever option you choose, focus on proper heater sizing, safe installation, and a sauna designed for your climate.
Ready to create your winter sauna setup?

Explore our outdoor sauna collection, discover our barrel saunas,
or browse our wood-burning sauna stoves and electric sauna heaters.