Outdoor wood-burning saunas operate by bringing a warm, comforting flame to logs to produce heat. To build and maintain a fire with the appropriate temperature for your sauna, you have to be sure that you are using the right logs. You may be unsure of what type of wood to use for your sauna stove and wish to know more about the best type of wood. Possibly, you are also curious about how to use your stove efficiently, as well as unsure of how to feed it properly or which stones to use. Here is more about the different types of logs you can use for your sauna heater. 

WHAT KIND OF WOOD SHOULD I USE FOR MY SAUNA HEATER? 

The best part about the fact that your sauna stove operates by using a wood flame is that you have a variety of options for fuel. Ultimately, any kind of wood can be used for your sauna heater.  While both softwoods and hardwoods can be used as fuel, here is where they differ:

SOFTWOODS

• Cheaper option
• Slower heating time w/ faster burn
• Absorbs heat from steam
• Great for starting the fire 

PINE

• Common types: White, Yellow, or Ponderosa
• Commonly used for:

           Furniture

           Roofing

           Framing

           Flooring

• Carving made easy by high flexibility 
• Easy to stain
• Readily available & easy-to-use

CEDAR

• Most popular: Western Red Cedar
• Commonly used for:

           Outdoor furniture

           Roofing

           Exterior building

           Decks

• Tougher than other softwood types
• Better at handling moist environments than other softwood types
• Reddish hue w/ aromatically-pleasing properties

REDWOOD

• Perfect for exposure to moisture
• Commonly used for:

            Patio furniture

            Home exteriors

            Garden fences

            High-quality projects (i.e.: pieces of art or a church organ)

• No premature rotting
• Does not warp easily 

FIR

• Also known as ‘Douglas Fir’
• Commonly used for:

           Buildings

           Christmas trees

           Projects that require painting

           Plywood

           OSB

• Turns into pulp after being processed
• More tough and durable than other softwoods

SPRUCE

• Features creamy-white lumber tone 
• Commonly used for:

            Musical instruments (i.e.: violins, guitars)

            Fences

            Boards

            Paper

• Turns into pulp after being processed
• More tough and durable than other softwoods
• Has rigid, scaly bark 

If you do decide to use softwood, the best options are cedar, spruce, and pine. In short, softwood is better when used for the construction of the sauna itself instead of being used for fuel. 

HARDWOODS

• More expensive option
• Slow, long burn
• Produces fruit or nut 
• Dormant during the wintertime
• Can thrive in temperate climates

OAK

• Highly popular
• Commonly used for:

           Furniture

           Flooring

           Cabinets

           Doors

           Trim

• Features medium-brown hue
• Often stained to medium-reddish brown tint

MAPLE

• Also highly popular
• Commonly used for:

            Furniture

            Flooring 

            Countertops

            Butcher blocks

            Trim

             Places requiring light-colored wood 

• Features creamy, beige tone
• Sometimes amber-yellow hue after staining 

WALNUT

• Hardly ever stained

• Commonly used for:

           Furniture

           Veneered pieces

           Features deep, dark-chocolate brown tone

           Sometimes lighter hue of dark brown

CHERRY

• Premier hardwood
• Commonly used for:

           Furniture

           Veneered pieces

           Trim

• Features reddish-brown tint
• Sometimes aged in appearance by staining (darker hue)

BIRCH 

• Similar grain pattern as cherry wood
• Commonly used for:

            Furniture

            Millwork

• Features light-brown hue
• Sometimes aged in appearance by staining (darker hue), similar to cherry

POPLAR

• Cost-friendly
• Used for utility purposes 
• Commonly used for:

            Upholstered furniture frames

            Veneered pieces

• Often stained to look like other expensive hardwoods (looks just like cherry when stained)

BEST WOOD FOR YOUR OUTDOOR WOOD-BURNING SAUNA

Due to their long, slow burn, hardwoods are often seen as better suited for the sauna stove. Here are a few key points to remember: 

• If possible, you should try to stick with using wood that you have a surplus of for stocking purposes.
• Recommended Fuel Wood Types: Oak, Birch, Maple, Ash, Grey Box, Ironbark 
• Recommended Building Wood Types: Cedar, Oak, Aspen, Pine, Hemlock, Spruce
• Trees that contain sap may release fumes or burning liquid when ignited and should be avoided. 
• Do not use painted or stained wood for your sauna heater, which can release harmful toxic fumes. 
• Be sure to use clean, seasoned firewood, which means it has been dried for an entire season.  
• Avoid using green wood that has been freshly cut from the forest. (Allow it to dry out until the moisture content has reached 20% or less.)
• To identify good quality wood that is able to withstand intense changes in temperature, look for smooth, unvarying color and no broken knots.

SAUNA STONES 

Using the correct sauna stones for your sauna heater is just as important as using the best type of firewood. Special stones are required for operation, meaning typical stones found by the river or embedded in the dirt will simply not work. The stones must be the correct weight for heat retention. 

BEST WAY TO FEED YOUR OUTDOOR WOOD-BURNING SAUNA

If you happen to be building your own sauna outside the home, you may be wondering if you should opt for an inside feed or an outside feed. It is recommended that you should settle on an inside feed, and here are three reasons why:

1. You will lose up to 25% of the heat inside the sauna if you choose to feed your stove from the outside.
2. Installing a chimney kit, which can be added on when purchasing a pre-built outdoor sauna, is cheaper than feeding through a wall. (metal framing and clearances required)
3. Feeding on the inside is aesthetically-pleasing, making the light cleanup required afterward worth it. 

SUMMARY

While any type of wood can be used for your outdoor wood-burning sauna, certain wood types are better than others for the job. Softwoods are better for building the exterior of your sauna due to slower heating time, faster burn, and heat absorption. A few examples of popular softwood types are pine, cedar, redwood, fir, and spruce. Although more expensive, hardwoods are better for your sauna stove because of their long, slow burn and ability to withstand drastic changes in temperature. Popular hardwood examples consist of oak, maple, walnut, cherry, birch, and poplar. 

Try to stock wood, if possible, and only use clean seasoned wood. Avoid wood containing sap, as well as painted, stained, or green woods. Be sure to use the correct sauna stones for your sauna heater and remember that an inside feed is best for the ideal sauna experience.

If you have any other questions or concerns about your sauna stove or any other sauna-related inquiries, be sure to always use My Sauna World as your trusted resource.