Osmosis resistant. Torrified (also spelled “torrefied”) wood neither swells up during humid summer months nor dries out due to dry winter air. Torrified wood will not shrink, warp, expand, or contract due to changing weather or humidity levels.
Torrified wood has been heat treated or roasted until it has nearly 0% internal moisture. The wood will not reabsorb moisture because its structure has been altered as a result of the heating process. This is not a chemical process, and it affects the wood all the way through, to its core. The wood can be sanded, shaped, cut, or otherwise processed — or even scratched or dented — without losing the effects of the treatment. The heat treatment can also enhance the visual appeal of the wood.
Several guitar manufacturers have begun using torrified maple necks on their instruments.