Sustainability
Thermowood has one of the strongest environmental profiles of any commercial building material not because of marketing, but because of what it doesn't do. No chemicals are added at any stage. No toxic waste is produced. And because the process permanently extends the service life of the wood, every board stores its embedded carbon for decades longer than an equivalent untreated board would.
Sourcing
All Thermosticks material originates from responsibly managed Nordic forests via SWM Wood's supply chain. Finnish forestry is among the most regulated in the world. Legal harvest volume is capped well below annual forest growth, meaning the total volume of Finnish forest has grown year over year for decades.
Chain-of-custody documentation tracing each board from forest parcel to kiln to mill ships with every order over 500 square feet. Project-specific documentation is available on request for architect specifications and sustainability reports.
The process itself
Thermal modification uses only two inputs: heat and steam. There are no preservatives, no copper, no arsenic, no borates, no resins, no surface coatings. The kiln's only emission is water vapor and trace extractives from the wood itself.
This is different from pressure-treated lumber, which is impregnated with copper azole or similar chemicals. It's different from tropical hardwood, which often arrives without full chain-of-custody. And it's different from engineered composites, which rely on adhesives and plastics that don't compost.
Carbon
Like any wood product, Thermowood is a net carbon store for the life of the building it's installed on. Approximately 1 kg of biogenic carbon is sequestered in every linear foot of our standard 3/4" 5-1/2" cladding.
Because the thermal modification process dramatically extends the wood's service life a Class 1 durability rating with 25+ year rot resistance that carbon remains stored for significantly longer than it would be in untreated softwood. The wood is, in effect, a long-lived carbon savings account.
Shipping
The honest counterweight: our wood does travel. From Finnish forest to North American project is approximately 4,500 miles, the bulk of that by ocean freight. Ocean shipping is one of the most carbon-efficient forms of freight transport per ton-mile, but it's not zero.
Once the material arrives in Charleston, SC, onward distribution by truck to projects across the US and Canada adds additional transport emissions. We're working toward a published Environmental Product Declaration that will quantify total transport emissions per square foot expected to be available in 2026.
End of life
Because Thermowood is chemical-free, it's disposable the same way untreated wood is:
- Composts naturally in commercial and home composting systems
- Suitable for biomass combustion with no hazardous emissions
- Safe for soil contact and agricultural reuse
- Can be reclaimed, re-milled, or re-purposed as feature-grade lumber
Pressure-treated lumber cannot be burned, composted, or placed in contact with food-producing soil. Thermowood has none of those restrictions.
Certifications and standards
Our wood is treated to the International ThermoWood Association's Thermo-D or Thermally Modified Timber specifications, depending on species. SWM Wood is a founding member of the Association and one of the original practitioners of the process.
Full environmental documentation including the Thermowood EPD from the Association, our SWM Wood chain-of-custody statement, and any project-specific requirements is available on request. Email sales@stickssupply.com.