Scrap Wood Disposal: Treated vs. Untreated Makes All the Difference

Not All Scrap Wood Is Equal

A 2x4 is a 2x4, right? Wrong. From a disposal standpoint, there are at least four categories of scrap wood, and mixing them up can cost you money, get your load rejected at a recycler, or create a genuine environmental hazard.

• Clean untreated wood — Standard dimensional lumber, plywood, OSB, and solid wood without paint, stain, or chemical treatment. This is the easy stuff.
• Painted or stained wood — Lumber with a finish on it. Latex paint is generally fine. Old lead paint (pre-1978) is not. Stained wood varies by product.
• Pressure-treated wood — Lumber treated with chemicals to resist rot and insects. Pre-2004 treated wood used CCA (chromated copper arsenate) — that's arsenic. Post-2004 uses ACQ or copper azole, which is less toxic but still regulated.
• Engineered wood with adhesives — Particleboard, MDF, and laminate contain formaldehyde-based resins. Not recyclable as clean wood.

The green-tinted stuff in your fence or deck? That's pressure-treated. The framing lumber in your walls? Probably clean. The IKEA bookshelf? Particleboard with laminate veneer. Each goes a different path.

Clean Untreated Wood: The Most Options

Clean lumber is the easiest construction material to dispose of responsibly. Your options in Oregon:

• Firewood — Clean, dry softwood (pine, fir, cedar) burns fine in a wood stove or fire pit. Cut to length, split, and stack. Free disposal that heats your house. Just don't burn plywood or OSB — the adhesives produce toxic fumes.
• Wood recycling — Several facilities in the Portland metro area accept clean wood for grinding into mulch, hog fuel (biomass energy), or animal bedding. Rates are typically $20 to $50 per ton — cheaper than mixed C&D disposal.
• Habitat ReStore — Habitat for Humanity ReStore accepts usable lumber in good condition. Full-length 2x4s, 2x6s, and plywood sheets are always in demand.
• Free listings — Post "free lumber" on Craigslist or Facebook Marketplace. Hobbyist woodworkers, DIYers, and gardeners will come get it — especially hardwood or longer pieces.
• Compost/mulch — Small branches, twigs, and untreated wood chips can go through yard waste programs in most Oregon cities.

Pressure-Treated Wood: Handle With Respect

Pressure-treated wood from before 2004 contains CCA — chromated copper arsenate. The arsenic in old deck boards, fence posts, and landscaping timbers is a real environmental concern. You cannot:

• Burn it (releases arsenic into the air)
• Chip it for mulch (contaminates soil)
• Compost it
• Send it to a wood recycler (contaminates the clean wood stream)

CCA-treated wood goes to the landfill. Period. It's classified as non-hazardous solid waste in Oregon, so standard transfer stations accept it, but it must be separated from clean wood. The EPA's guidance on CCA is clear: disposal in lined landfills is the accepted method.

Post-2004 treated wood (ACQ/copper azole) is less toxic but still shouldn't be burned or mulched. Same landfill disposal path, but without the arsenic anxiety.

How to tell the difference? Look for end tags or stamps. CCA wood was typically stamped with the treatment type. If there's no stamp and the wood is old, green-tinted, and was used for ground contact — assume CCA and handle accordingly.

Scrap Wood Disposal Costs

For mixed wood loads from a renovation or demolition, a construction debris removal service sorts and routes each type appropriately. You don't have to figure out which pieces go where.

Renovation Generating Scrap Wood?

Most renovation and demo projects generate a mix of all four wood types. The framing is clean, the deck boards are treated, the trim is painted, and the cabinets are particleboard. Sorting at the jobsite saves money on disposal — clean wood is half the cost (or free) to dispose of compared to mixed loads. But if sorting isn't practical, a junk removal crew handles the logistics. Get a quote and get that wood pile out of the driveway.