Clean, coated and treated timber, where each one goes
Clean wood, meaning timber with no paint, glue or preservative, is chipped and commonly turned into panel board, animal bedding or landscaping products. Coated and manufactured wood, such as painted doors, laminate, chipboard and MDF, is usually chipped for board manufacture or burned as biomass fuel to generate energy. The sorting happens at the facility, so a mixed load is not a problem. Around 90% of everything we collect is recycled.
Treated timber is the one to watch. Wood that has been pressure treated or coated with creosote, including old railway sleepers, telegraph poles and some fence posts, should not be burned at home or chipped for garden use, and it goes down a separate route. If you know or suspect that some of your wood is treated, say so when you send the photo. The builders waste disposal guide has more on separating materials on site.

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