How to Maintain Your Outdoor Sauna (Year-Round Guide)

The Good News — Outdoor Saunas Are Low Maintenance

If you've been holding off on buying an outdoor sauna because you're worried about upkeep, here's some reassurance: maintaining one is genuinely easy. Cedar — the wood used in every LeisureCraft sauna we carry — is one of the most naturally durable and weather-resistant woods available. It resists moisture, repels insects, and handles temperature swings better than almost any other building material.

In practical terms, regular outdoor sauna maintenance amounts to roughly 30 minutes per month and a couple of hours of deeper cleaning every season. That's a small investment for a structure that, with proper care, can last anywhere from 15 to 25-plus years. The goal of this guide is simple: give you a clear, realistic picture of what sauna care looks like so you can enjoy your investment without stress or guesswork.

After Every Session

Post-session habits are the foundation of good sauna maintenance. The good news is that most of this takes less than five minutes.

• Leave the door open for 15 to 30 minutes. This is the single most important habit you can build. Letting air circulate after each use allows residual moisture to escape and the interior wood to dry completely. Trapped moisture is the primary cause of mold and wood degradation over time.
• Wipe down the benches if needed. If you place a towel on the bench during your session — which we highly recommend — there's usually very little to wipe up afterward. But if sweat has soaked into the wood, a quick pass with a dry cloth goes a long way.
• Clear the heater area. Make sure no towels, ladles, or debris have fallen near the heater rocks. Keeping the heater zone clean protects both the unit and the wood around it.
• Empty the water bucket. If you use water for steam, don't leave standing water in the bucket inside the sauna overnight. Empty it, let it dry, and store it upside down or outside.

None of this is complicated. Build these habits on day one and they'll feel completely automatic within a week.

Monthly Maintenance

Once a month, set aside 20 to 30 minutes for a slightly more thorough check. This is where you catch small issues before they become larger ones.

• Sand the bench surfaces lightly. Over time, bench wood can develop rough patches or minor staining from use. A light pass with fine-grit sandpaper (around 120-grit) keeps the surface smooth and pleasant. This also removes the top layer of any sweat-absorbed wood, refreshing the cedar underneath.
• Check door hardware. Give the hinges and latch a quick inspection. A loose hinge or sticking latch is a 90-second fix with a screwdriver — ignore it long enough and you're looking at a door that won't seal properly.
• Inspect the heater stones. Pull the rocks out or examine them in place. Replace any that are cracked, crumbling, or noticeably reduced in size. Compromised rocks heat unevenly and can break apart during use, which is a headache to clean up.
• Clean the floor. A mild soap and water solution is all you need. Avoid anything with bleach, ammonia, or harsh detergents — they damage cedar and, more importantly, they off-gas toxic fumes when the sauna heats up.
• Clear ventilation openings. Check that your intake and exhaust vents aren't blocked by debris, spider webs, or accumulated dust. Good airflow keeps the sauna comfortable and prevents excessive humidity buildup in the wood.

Seasonal Deep Clean (Every 3 to 6 Months)

Two to four times per year, give your sauna a more thorough going-over. This is especially worthwhile at the transition between seasons.

• Scrub interior wood surfaces. Use a sauna-safe wood cleaner or a diluted white vinegar solution (roughly one part vinegar to four parts water). Work with the grain of the wood and let the surface dry thoroughly before your next session.
• Sand and clean benches more thoroughly. Go a little deeper than your monthly pass — especially on areas that see the most contact.
• Examine the exterior wood. Look for signs of weathering, surface mold, or mildew — particularly in areas that stay damp, like the underside of overhangs or spots near ground level. Address mold immediately with a diluted vinegar wipe-down and ensure proper drainage around the base.
• For barrel saunas: check the metal bands. Models like the Canadian Timber Harmony Barrel Sauna use metal bands to hold the staves together. Cedar expands and contracts with seasonal temperature changes, so these bands need periodic tightening — a wrench and five minutes is all it takes.
• Inspect the roof or top staves for water intrusion. For cabin-style models like the Canadian Timber Luna Sauna, check that roof panels are seated properly and that there are no signs of water pooling or penetrating the wood. For barrel models, check the top staves for any gaps that have widened over time.
• Clear the base perimeter. Remove any accumulated leaves, dirt, or plant matter from around the foundation. Organic debris holds moisture against the wood and accelerates weathering at the base of the structure.

Protecting the Exterior Wood

One of the most common questions we get about cedar sauna maintenance is what to do about the changing color of the wood. Here's the straightforward answer: untreated cedar naturally fades from its original warm honey tone to a silvery gray when exposed to UV light. This is purely cosmetic — the wood is not weakening or degrading.

You have two valid options:

• Preserve the original color: Apply a UV-protective exterior wood stain or sealant once a year. Choose a product rated for outdoor wood that is also sauna-safe — meaning it contains no toxic compounds that could off-gas in heat. Apply to exterior surfaces only.
• Let it go natural: If you like the rustic silver patina — and many sauna owners do — simply leave the exterior untreated. No maintenance required beyond your seasonal inspection.

What you should never do: apply paint or polyurethane to any part of your sauna, inside or out. These coatings trap moisture in the wood and release harmful fumes when heated. The interior wood should always remain bare and unsealed — it's designed to breathe.

Winter Care

Outdoor saunas are engineered to perform in all four seasons. Winter use isn't just possible — it's one of the best ways to use a sauna. The contrast between stepping into 170°F dry heat and then cooling off in cold air (or snow) is an experience that's hard to beat.

That said, winter does require a few additional habits:

• Clear snow from the roof and base after storms. Heavy snow accumulation can stress roof structures, and snow packed against the base holds moisture against the wood for extended periods.
• Check your door seal. Cold air drafts around a worn or improperly fitted door make your heater work harder and increase preheat time. If you notice the seal is worn or the door doesn't close snugly, address it before the coldest months hit.
• If the sauna will sit unused for weeks: Make sure it's fully dry before closing it up, and leave a small vent gap so air can continue to circulate inside. A sealed, damp sauna in winter is an invitation for mold.

What NOT to Do

Avoiding common mistakes is just as important as the positive maintenance steps. These are the errors we see most often — and the ones most likely to cause real damage:

• Don't use bleach or harsh chemical cleaners inside the sauna. They degrade cedar and create toxic fumes when the sauna heats up. Stick to mild soap, diluted vinegar, or products specifically rated as sauna-safe.
• Don't pressure wash the interior. The force is too aggressive for sauna wood and will raise the grain, splinter surfaces, and drive moisture deep into the structure. The exterior can be pressure washed gently from a distance — the interior cannot.
• Don't leave wet towels or damp items inside after sessions. Anything that holds moisture and sits inside a closed sauna is a mold risk. Take everything out, leave the door cracked, and let the interior breathe.
• Don't seal the interior wood. Cedar needs to absorb and release moisture as part of its natural function in a sauna environment. Sealing it disrupts that cycle and can cause the wood to warp or crack.
• Don't ignore small issues. A loose band, a sticking door latch, or a cracked heater rock is a minor fix today. Left unaddressed, each one has the potential to become a more involved repair. Small problems are your early warning system — use them.

Frequently Asked Questions

How often do I need to stain my outdoor sauna?

If you want to preserve the original warm cedar color, apply a UV-protective wood stain to the exterior once a year. If you prefer the natural silver-gray patina that develops over time, no staining is needed at all — just enjoy the weathered look.

Can I pressure wash the outside of my sauna?

Yes, you can pressure wash the exterior on a gentle setting, keeping a safe distance from the wood surface. Never pressure wash the interior — the force is too damaging to sauna-grade wood and will cause long-term surface degradation.

How do I get rid of sauna odor?

Start by running a full hot session with the door open for about 30 minutes — this purges most odors naturally. For persistent smells, lightly sand the interior bench surfaces and any other affected wood. Sanding removes the absorbed layer and exposes fresh cedar underneath, which has its own naturally pleasant scent.

Do I need to replace sauna rocks?

Check your heater rocks every few months as part of your regular maintenance routine. Replace any that are cracked, crumbling, or noticeably smaller than when you started. Most quality sauna stones last one to three years depending on frequency of use. Fresh rocks heat more evenly and produce better steam.

A well-maintained sauna is a sauna that lasts a lifetime. Browse our full LeisureCraft collection — built from premium Canadian cedar and designed for years of reliable outdoor use in any climate.