Thermally treated wood is great, looks good, resists the elements, is more durable (but more brittle) and is free of pressure treated chemicals. https://en.wikipedia.org/wiki/Thermally_modified_wood?wprov=sfti1 There are certainly economies of scale in the process but as I’ve seen the product is still priced at a huge premium despite its benefits. Has anyone tried building their own box to dry and pressure roast a few board feet for your own use?