Dark Thermo Alder Sauna Wood: Alder, Black Alder Alnus glutinosa
What makes Dark Thermo Alder a good choice for a modern Finnish sauna?
If you are looking for a premium dark sauna timber with a modern, meditative aesthetic, dark thermo alder is a great choice. Dark thermo alder is extremely durable and water-repellent, making it an ideal sauna wood. Our dark thermo alder is produced by thermally modifying alder, Alnus Glutinosa, which is ethically sourced from the Nordic and Baltic provinces.
Dark thermo alder sauna cladding and bench boards are produced from grade A alder as per the Nordic Timber Grading standards. Dark thermo alder is soft, porous and has a straight grain. This sauna timber type is free of knots and does not weep malt or resin. The intense thermal modification process further increases the heat capacity of the sauna wood, which means that it does not get hot to touch and makes it a popular timber choice for any home sauna.
The intense thermal modification process where the wood is treated in minimum 215 degrees Celsius centigrade creates a beautiful, deep dark chocolate brown colour and the distinctive toasted scent of dark thermo alder. Although some are drawn to this sauna timber specifically because of its unique strong aroma, others may find it overpowering.
Thermowoods, such as dark thermo alder, make a great sauna wood choice because the raw wood becomes incredibly durable, dimensionally stable and rot resistant. Dark thermo alder is an ideal choice for a sauna that is in frequent use because of its longevity.
Dark thermo alder sauna cladding and bench boards are easy to maintain with sauna cleaning products and paraffin oil. Although this wood type does not show stains as easily as many lighter sauna woods, we would recommend treating it with care through the use of products that are designed for saunas.
When should I consider dark thermo alder wood cladding and benches for my home sauna?
- The sauna is in frequent use
- There will be children in the sauna
- You are looking for a lower density wood that is easy to work with
- You prefer a dark, premium sauna timber with a modern aesthetic and a meditative feel
- You like a strong, toasted aroma in your home sauna
Recommended wastage allowance: Intensely thermally modified dark thermo alder is resilient but the intense thermo treatment process can make this sauna wood more brittle and therefore we recommend a higher wastage allowance of 20-25% when ordering wood for your sauna installation. We also recommend ordering a size larger than required so that you can cut either end shorter with a chop saw or similar, to get a fresh clean edge and reduce the chance of transit end damage propagating into splits.
Dark Thermo Alder is available in the following sauna timber profiles and dimensions:
STEP Profile Tongue and Groove Sauna Wood Cladding: 27mm thick by 64mm wide
STS4 Profile Tongue and Groove Sauna Wood Cladding: 15mm thick by 120mm wide
STP Profile Tongue and Groove Sauna Wood Cladding: 15mm thick by 85mm wide
SI Profile Sauna Moulding: 14mm thick by 30mm wide
KA Profile Sauna Moulding: 14mm thick by 60mm wide
Sauna Wood Bench Boards: 27mm thick by 42mm, 85mm, 115mm and 135mm wide
You can find our dark thermo alder sauna wood products below.
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