Thermally modified wood is a newer form of lumber suitable for use outdoors. It is a broad category ranging from the very traditional, low-tech but beautiful Shou Sugi Ban to high-tech woods steamed in oxygen-free chambers. The overarching concept here, though, is a treatment of wood using heat, rendering it resistant to insects and decay. Regardless of the method, the result is the removal of compounds in the wood that are foodstuffs for insects and mold, mildew, and fungi.

A primary difference here is that Shou Sugi Ban and other forms of flame treatment alter the appearance and are directly associated with the aesthetic. Contrast this with the modern forms of thermally modified woods which seek to preserve the original wood character. Among these modern woods, you find two general categories. First, you have products that are manufactured from mostly but not exclusively softwoods. These products often use wood species that might be considered mundane and are enhanced with dye or other coloration agents. Another form of Thermal wood starts with species that have inherent aesthetic value that is made durable and/or enhanced through the heat-treating process.

In a world that is increasingly shifting towards synthetic wood substitutes, thermally modified wood offers a welcome respite from the synthetic without giving up durability. This type of lumber has the potential to fill voids left by scarcity in both temperate softwood and tropical hardwood forests.

As is evident below the efficacy of thermally modified decking and siding is self-evident.