About Therma Wood Technologies

Why TWT?


  •  PRODUCTIVITY:  Our system has a far shorter process time than all other equipment in the industry.  This is the most advanced thermal modification process on the market. It is a closed vacuum system and has the ability to modify 4500 board feet of wood in 8 hours or less (versus 48/72 hours in the typical “open” systems which use no vacuums).  As a result, our system has a far lower energy consumption and has the ability to produce significantly more product in a much shorter time frame.


  • DURABILITY :  Traditional systems produce a product where Durability is rated as a Class 2 for pine, spruce etc. Our Durability is rated as a Class 1.


  • STABILITY :  Our modification process occurs at much lower temps due to the use of higher pressure.  This method avoids brittleness, checks and mechanical degradation of the wood.  Because we utilize a scientific process, we produce a far more Stable product with much lower scrap rates and corresponding cost savings.


Therma Wood Technologies Plant-3

Therma Wood Technologies Manufacturing Plant in Polson, MT


rot resistant wood siding

About Us

Therma Wood Technologies (TWT) is one of the largest processors of Thermally Modified Wood (TMW) in North America and is based in Polson, Montana.

Utilizing state of the art European technology and North America wood, TWT utilizes the most technologically advanced equipment in the thermal wood industry. Our Autoclave can produce over 3 million board feet annually.  There is such a demand for Thermally Modified wood processed this way that we are adding a second Autoclave system in July, 2021 to meet our customers needs.

As the needs of our customers have developed, so has our process and internal operation. Our sole focus is to be the best processor/producer of Thermally Modified Wood in North America and as a result, we only offer modification services to our customers.

Our customers provide the raw material,

we make it better.

Within our current operation, we are focused on modifying several Softwood species, including Clear Vertical Grain Western Hemlock, Small Tight Knot Hemlock, Ponderosa Pine, Southern Yellow Pine and Douglas Fir. Currently, 85% of the wood we modify for our customers is used for siding, with the balance used for soffit, decking and other exterior projects. We expect that to change as our customers continue to diversify their TMW product lines. Along with significant domestic growth we are seeing strong growth in our overseas markets; particularly in New Zealand, Australia and the U.K.



Our Autoclave is capable of producing over 3 million board feet annually.



As we continue to enhance and perfect our modification processes, we are also adding to our facility in Polson with a 2021 expansion that will allow us to have 4 Autoclaves onsite by the end of 2022.

In conjunction with our European equipment manufacturers, our customers and our University Wood Science partners we are collectively committed to creating and developing the best TMW product and standards in North America.

Durable Thermally Modified Decking for Docks-28


Unmatched sales-related experience supported by operational excellence.  A Senior Leadership Team with significant experience and prior success in Manufacturing, Production, Construction and Sales utilizing wood products makes TWT a leader in the thermally modified wood industry.