Weathering
The natural degradation and color change of wood surfaces exposed to sunlight, rain, wind, and temperature fluctuations, typically turning gray or silver with a roughened texture.
In-Depth Explanation
Weathering is a surface phenomenon driven primarily by UV radiation breaking down lignin, the natural polymer that binds wood fibers and gives wood its color. As lignin degrades, the surface turns gray or silver as the remaining cellulose fibers are exposed. Rain washes away degraded fibers and raises the grain, while wetting and drying cycles cause surface checking and roughening. The depth of weathering is typically shallow but it significantly affects appearance and can lead to deeper decay if moisture penetrates cracks. UV-blocking finishes, pigmented stains, and regular maintenance can slow weathering, while some architects intentionally allow wood to weather to a silver-gray patina.
Usage Example
The cedar fence was left unfinished intentionally and developed a beautiful silver-gray weathered patina within two years.