Thermo Alder Sauna Wood

Thermo alder is one of the most popular choices for home and commercial saunas — and for good reason. Ethically sourced from Nordic and Baltic forests, our thermally modified alder offers a warm hazel brown tone, exceptional durability, and a clean, modern aesthetic. Through an all-natural heat and steam process, this grade A sauna wood becomes darker in colour, more stable, and more resistant to moisture — making it ideal for the high-heat, high-humidity conditions of a traditional sauna.

Whether you're building cladding or bench boards, thermo alder provides a long-lasting, resin-free solution that looks beautiful and performs flawlessly.

No products found
Use fewer filters or remove all

Thermo Alder: A Premium Grade Sauna Timber for a Warm, Modern Finish

Thermo alder is a popular sauna wood for the following characteristics:

  • Natural Durability - Thermal modification enhances alder's resistance to decay and reduces moisture absorption, preventing warping or cracking.
  • Safe & Comfortable - With its low thermal conductivity, thermo alder doesn't overheat, making it ideal for saunas used frequently by families.
  • Beautiful Appearance - The thermal process deepens alder's natural colour to a warm golden or hazel brown, with a straight grain and knot-free finish.
  • Lightweight & Easy to Work With - Thermo alder's reduced density makes it easier to handle during installation.
  • Versatile Use - Suitable for cladding, bench boards, skirting, and sauna accessories.

Recommended Wastage Allowance

Thermo alder is a strong, splinter-free sauna wood, but we suggest a 15% wastage allowance to account for trimming, fitting, and potential transport damage.

Everything You Need