Care Guide: SaunasUpdated 17 minutes ago
Maintaining your sauna after installation
Your sauna is ready to use as soon as it is assembled. We recommend treating the outside with a UV-protective treatment before first use (see Exterior care below), although the sauna will still work normally without it. A little routine care will keep it dry, protected and looking its best for years to come.
Important - warranty: Your sauna has a 1-year warranty, which remains valid as long as the sauna is used and maintained following this care guide. Regular exterior re-treatment is recommended, but it is not a condition of the warranty.
Materials and factory finish
The walls, benches, floorboards, heater guards and headrest are TMT spruce, thermally modified at the factory. This is the only treatment: no coating, paint or stain is applied, and the finish is natural.
| Part | Material | Finish |
|---|---|---|
| Walls, benches, floorboards, heater guards, headrest | TMT spruce (thermally modified) | Natural - no coating, paint or stain |
| Ground beams (foot base) | Red cedar | Coated with black paint |
| Thermometer | Heat-stabilised pine | - |
| Bucket and spoon | Pine | Untreated. The bucket has a plastic liner. |
Exterior care
Over time the outside will turn grey. This is natural weathering, but if the wood is left untreated long-term it gradually loses its protection.
- To protect the wood, treat the outside only with a water-based stain-and-seal with UV protection. Any suitable brand can be used.
- We recommend applying it before first use, then re-coating once a year. Without this step the sauna still works normally, but the exterior timber will fade faster.
- Alternatively, you can re-coat whenever the colour fades or greying appears. How often depends on the sun and weather where you live.
- Before re-treating, clean the wood and let it dry fully, then lightly sand if needed. Follow the stain manufacturer's instructions for the number of coats.
Covering your sauna: If you cover your sauna, use a breathable cover. Non-breathable covers trap moisture and cause mould.
Rain and roof
The sauna is not fully waterproof. A little water may seep in during wind-driven rain. This is normal and will not damage the sauna.
Leaks in light rain: If water gets in during light rain, this is not normal. Check for lifted or damaged roof shingles, an exposed roof membrane, or any assembly issues, using the troubleshooting section of your instruction manual.
- After heavy rain, you can run the heater for 30-60 minutes with the door closed to dry out the room.
- Replace any cracked roof shingles promptly.
Interior care
- Leaving the inside untreated is the safest option, as it avoids any fumes when the sauna is heated.
- If you would like to protect the wood, a sauna-grade paraffin oil such as Harvia Paraffin Oil can be used. This is entirely optional. Never use ordinary paraffin lamp oil.
- Do not paint, varnish or use any other treatment on the inside.
- Clean with Harvia Sauna Cleanser or a mild soap that is safe for wood. Avoid ammonia and harsh chemicals.
- Lightly sand any marks or stains on the benches, always along the grain.
- Avoid leaving standing water inside the sauna.
After each use
- Switch the heater off and leave the door ajar or open so the sauna can air out and dry naturally.
- Remove towels, buckets and anything else from inside. Do not store items in the sauna.
Optional: In bad weather, in very dusty conditions, or if you need the sauna to dry quickly, you can instead run the heater for 30-60 minutes with the door closed, then switch it off and open the door.
Preventing and treating mould
The best prevention is to dry the sauna fully after every use.
- If mould appears, gently scrub the area with a soft brush and mild soapy water (household white vinegar can also help), then lightly sand any remaining marks along the grain.
- Only if that does not remove it, use a stronger cleaner such as 30 Seconds Outdoor Cleaner or Behr All-in-One Wood Cleaner. Make sure any cleaner you use is suitable for wooden saunas.
Please note: Wear protective equipment (gloves, goggles and a mask), and throw away any cloths or brushes that touched the mould.
Accessories
| Accessory | How to care for it |
|---|---|
| Heater guards and headrest | Best left untreated. If you wish, you can optionally treat them with sauna-grade paraffin oil or Supi Sauna Wax. Clean the guard only when the heater is off and cool: wipe with a damp cloth and lightly sand any marks. |
| Bucket and spoon | Rinse with clean water and let them air-dry. Don't leave the bucket soaking. |
| Thermometer | Wipe with a soft, dry cloth. |
Do not use strong chemicals on any accessory.
Regular checks
- Inspect the stainless steel bands regularly and re-tighten them when they are loose.
- Keep the underside of the sauna clear so the wood can dry. Only the cradles should touch the base.
- Check the drainage around the base every season.
Please be reassured: Minor cracks, small gaps between staves and slight swelling are normal for TMT spruce, caused by natural wood movement. No action is needed unless the gaps become large.
Winter and periods without use
- Keep the inside dry. Use a dehumidifier (empty the tank regularly) or a fan to keep air moving.
- Place moisture absorbers, such as charcoal, Damp-Rid or cat litter, in dishes around the inside of the sauna.
What to avoid
Do not: use pressure washers, bleach, ammonia, solvents, abrasive pads or harsh chemical cleaners; use non-breathable or tight plastic covers; use ordinary paraffin lamp oil, paint or varnish inside the sauna; or leave standing water in or around the sauna.