Maintenance
How to Maintain an Outdoor Sauna: A Complete Guide
A practical guide to maintaining a Wellness One outdoor sauna — cleaning, wood treatment, heater maintenance, and seasonal care.
By Wellness One Lifestyle · Published 2026-08-02 · Updated 2026-08-02
Maintaining Your Wellness One Outdoor Sauna
Wellness One saunas are built to last 25 years. With straightforward maintenance, your sauna will perform at its best throughout its lifetime.
After Each Use
- Allow the sauna to cool completely before closing the door
- Wipe down the benches and floor with a clean cloth
- Leave the door slightly ajar to allow air circulation and prevent moisture build-up
- Remove any water from the heater stone tray
Weekly
- Check the heater stones — remove any that have cracked or disintegrated
- Wipe down the interior walls and benches with a mild sauna cleaner
- Check the door seal for any signs of wear
Monthly
- Inspect the exterior cladding for any signs of moisture damage or discolouration
- Check all fixings and hinges are secure
- Inspect the roof for any signs of water ingress
Annually
- Treat the exterior cladding with a suitable outdoor wood oil or stain. Thermowood Oiled cladding should be re-oiled annually. Thermo Ayous cladding should be treated with a light oil. Black Charred cladding requires minimal treatment.
- Check the heater element — replace if efficiency has reduced
- Inspect the electrical connections (by a qualified electrician)
Interior Wood
The thermally modified aspen interior requires no treatment. Thermally modified wood is naturally resistant to moisture, bacteria, and mould. Do not apply any oil or stain to the interior wood.
The 5-Year Guarantee
Every Wellness One sauna carries a 5-year guarantee. If any component fails within the guarantee period, the Wellness One team will repair or replace it at no cost.
Frequently Asked Questions
How do you maintain an outdoor sauna?
Outdoor sauna maintenance is straightforward. Clean the interior after each use, treat the exterior wood annually, and check the heater stones periodically. Wellness One saunas use thermally modified aspen interiors that require minimal treatment.
How often should you treat sauna wood?
The exterior cladding should be treated annually with a suitable outdoor wood oil or stain. The interior thermally modified aspen requires no treatment — it is naturally resistant to moisture and bacteria.