Wood treated with thermal modification has been through a natural, non-toxic process that basically cooks the wood, changing the make-up of the wood. Wood is heated in 400+ degree heat in an oxygen-free environment.

How is Thermally Modified Wood Physically Different?

Thermal modification uses heat to remove organic compounds from the wood cells, so it will not absorb water, expand, contract, or provide nourishment for insects or fungi. The high heat produces a naturally durable wood that is permanently resistant to water, insects, and decay. Because the wood is not absorbing chemicals to be treated, but rather removing moisture, the wood is lightweight.

Thermally modified lumber is also more dimensionally stable because it is less susceptible to cupping and warping. The wood has increased heat resistance and weather resistance as well. When properly maintained, it will not chip, rot, or warp over the years. Many products offered in this category are rated for 20 or 25 years of exterior use.

How Does Thermally Modified Wood Look Different?

The high gradual heat process creates permanent reactions and gives the wood a rich, deep brown appearance. The darkened color brings an unexpected tropical look.


The chocolate color can be maintained in exterior applications by finishing the wood with a UV-inhibitor sealant on all sides and ends of the wood. If not finished, the wood will naturally weather to a shade of gray because of exposure to the sun’s ultraviolet rays.

What Can Thermally Modified Wood Be Used For?

Since thermally modified wood does not absorb or hold moisture as it would prior to treatment, species that typically do not perform well in outdoor or wet environments can now be used in a variety of applications, such as decking, siding, or flooring. It can also be used in environments that are less stable in moisture content, such as basements (with proper sub-flooring).

The Benefits of Thermally Modified Lumber

This thermally modified wood is eco-friendly since harsh chemicals are never used in the development of this product. Unlike pressure-treated lumber, it will not corrode metals. As previously mentioned, it is also dimensionally stable with incredible durability.

A New Non-Toxic Product for Outdoor and Indoor Use

Thermally modified lumber is a green alternative to tropical hardwoods and pressure treated lumber for exterior uses and is an beautiful product to use in other applications where stability and durability are key variables.

Interested in learning more about thermally modified lumber? Visit our distributors list to find a distributor in your area.