Sauna Mold: Why It Happens and How to Prevent It
Mold doesn’t care how expensive your sauna is—or how often you use it. If you’re combining high heat, humidity, and porous wood without a consistent maintenance routine, you’re creating the perfect conditions for mold to thrive. In this guide, we’ll explain why sauna mold happens, how to spot it early, and most importantly, how to prevent it from ruining your investment.
Why Mold Grows in Saunas
Saunas are warm, humid, and made of absorbent materials like cedar, spruce, or hemlock. That’s a paradise for mold spores, especially if moisture is allowed to sit too long on the wood surface.
Common causes include:
- 🚫 Lack of ventilation after sessions
- 🚫 Not wiping down benches or walls
- 🚫 Skipping cleanings or using improper products
- 🚫 Repeated water application to rocks without air circulation
How to Spot Sauna Mold Early
- 👃 Musty, earthy odor (especially after sessions)
- 👁 Dark blotches or speckled stains on benches or walls
- 👆 Sticky or oily wood texture
- 😬 Skin irritation after using the sauna
How to Prevent Mold in Your Sauna
- ✅ Always ventilate: leave the door open post-session for at least 30 minutes
- ✅ Use a clean towel between your skin and the bench
- ✅ Wipe down wood surfaces after each use with a dry cloth
- ✅ Deep clean weekly with a plant-based, wood-safe sauna spray
- ✅ Avoid overwatering rocks unless ventilation is excellent
What If You Already See Mold?
If you’ve got visible mold or a lingering smell, it’s time to act fast:
- 🧼 Deep clean the interior with a sauna-safe solution
- 🪵 Consider sanding lightly if the mold is surface-level only
- 🔁 Replace rocks and check the heater cavity
- 💨 Let the sauna dry out fully with fans or natural airflow
Recommended Sauna Cleaner
Our plant-based sauna cleaner was developed to gently clean and deodorize wood surfaces without using harsh chemicals that could damage your sauna or leave behind unsafe residue. While we don't claim it kills mold, it’s effective at maintaining a fresh, clean sauna and discouraging the conditions mold thrives in—especially when used consistently.
Final Thoughts
Preventing sauna mold is simple if you stay ahead of it. Keep your space ventilated, wipe it down after each use, and use a wood-safe cleaner at least weekly. It’s a small effort that keeps your sauna beautiful, safe, and long-lasting.