How to restack stones:

1. Let the heater cool completely and switch off the power at the breaker.
2. Remove all stones and set them on a towel.
3. Vacuum the dust and stone fragments from the heater tray.
4. Rinse good stones in plain water. Discard any that are cracked, flaky or crumbling.
5. Restack loosely: largest stones at the bottom, smaller on top. Leave gaps for air to flow, and make sure no element is exposed.

Use only stones sold for saunas, such as peridotite, olivine-diabase, or vulcanite. River and garden rocks can contain moisture and may crack violently when heated.

Water for steam

Use clean tap water when throwing water on the stones. Avoid salt water, pool water or heavy oils, which corrode elements and leave residue.

If you add scents, choose sauna-specific aromas diluted in the water bucket. Never pour pure essential oil on hot stones.

Wood-burning sauna stoves

• Empty the ash pan regularly, once ashes are completely cold.
• Burn only dry, untreated hardwood. Never burn painted wood, plastic or trash.
• Have the chimney swept and inspected at least once a year.
• Check the stove body, door gasket and flue joints for cracks or gaps.

Infrared sauna panels

• Wipe emitters with a dry, soft cloth only. Never spray water or cleaner on them.
• Check that cables, connections and the control panel are secure and undamaged.
• Keep panels clear of towels and clothing.

Ventilation, moisture and mold prevention

Moisture is a sauna’s number one enemy. Heat alone won’t stop mold if the room stays damp between sessions.

Daily habits that prevent mold

• Dry it out after every session. Prop the door open and open the vents for at least 1–2 hours.
• Run a short dry cycle. Leaving the heater on for 15–30 minutes after use (with vents open) drives out remaining moisture.
• Never leave wet items inside. Damp towels, mats, and buckets keep humidity high overnight.
• Keep vents clear. Check that intake and exhaust vents are not blocked by dust, towels or furniture.

How to spot mold or mildew early

Look for black, green or white fuzzy spots, especially under benches, in corners and along the floor. A persistent musty smell is often the first warning sign.

How to remove mold from a sauna

1. Ventilate the room and wear gloves and a mask.
2. Scrub small spots with a 50/50 solution of white vinegar and water, or 3% hydrogen peroxide.
3. Let it sit for 10–15 minutes, then wipe clean.
4. Lightly sand any remaining discoloration.
5. Dry the sauna fully by heating it with the vents open.

If mold covers a large area, keeps returning, or appears inside walls, call a professional. It usually points to a ventilation or vapor-barrier problem.

Outdoor and barrel sauna care

Outdoor saunas face sun, rain, wind, dust, and temperature swings. Their exteriors need their own care routine. Sauna Maintenance Guide: How to Keep Your Sauna Perfect

• Treat the exterior wood. Apply a UV-resistant exterior wood stain or oil every 1–3 years, depending on sun exposure. Never treat the interior with the same product.
• Tighten barrel bands. Barrel saunas expand and shrink with humidity. Check the steel bands every few months and adjust them as the manufacturer advises.
• Inspect the roof. Look for lifted shingles, cracked roofing or leaks after storms.
• Keep the base dry. Clear leaves, sand and debris from around the base. The sauna should sit on a level, well-drained foundation.
• Check for pests. Seal small gaps where insects or rodents could get in.

Climate-specific tips

Hot, sunny and dusty climates (e.g., desert and Gulf regions): Strong UV fades and dries exterior wood quickly, so re-oil more often. Wipe sand and dust from vents, door seals and the heater area weekly. A shade structure or cover extends the life of the exterior.

Humid and coastal climates: Ventilation matters even more. Dry the sauna after every use and check for mold weekly. Salt air can corrode metal fittings, so inspect hinges, bands and screws regularly.

Cold and snowy climates: Clear heavy snow from the roof. Check for ice damage at seals and the chimney after winter.

10 sauna maintenance mistakes to avoid

1. Using bleach or harsh chemicals. They damage wood fibers and release toxic fumes when heated.
2. Pressure washing the interior. It forces water deep into the wood and can damage electrics.
3. Soaking the wood. Too much water causes warping, cracks and mold. Damp is enough.
4. Varnishing or painting benches. Coatings get sticky and hot, and trap moisture.
5. Cleaning while the sauna is hot. Cleaners evaporate instantly and you risk burns.
6. Ignoring crumbling stones. Packed debris overheats elements and shortens heater life.
7. Using non-sauna rocks. Ordinary rocks can split or burst under heat.
8. Closing the door straight after use. Trapped moisture is the main cause of mold.
9. Pouring essential oils directly on stones. Undiluted oils can ignite and leave residue.
10. DIY electrical repairs. Heater wiring and controls should only be handled by a qualified electrician.

Sauna cleaning tools and supplies

You don’t need much. Keep this simple kit in one place so cleaning takes minutes, not hours.

When to call a sauna professional

Most care is easy to do yourself. But some warning signs need an expert. Call a qualified sauna technician or electrician if you notice:

• The sauna takes much longer than usual to heat up (most reach temperature in 30–60 minutes)
• The heater trips the breaker, sparks, hums loudly or smells like burning plastic
• Visible damage to elements, wiring or the control panel
• Mold that keeps returning or spreads behind wall panels
• Smoke leaking into the room from a wood-burning stove or chimney
• Warped, rotting or loose wall boards, benches or flooring
• Water leaks from the roof of an outdoor sauna. Sauna Maintenance Guide: How to Keep Your Sauna Perfect

A yearly professional inspection is a smart habit, especially for heavily used, commercial or wood-burning saunas.