How to Recycle Wood/Lumber
Construction lumber, dimensional timber, and wood debris from building projects, renovation, and demolition activities. Wood comprises a significant portion of construction waste, with untreated lumber being highly recyclable into mulch, biomass fuel, and engineered wood products, while treated lumber requires specialized handling due to toxic preservatives including arsenic, chromium, and creosote that pose serious health and environmental risks.
- 1Identify and separate treated from untreated wood - treated lumber often has green tint or stamps
- 2Remove all metal fasteners including nails, screws, bolts, and brackets using appropriate tools
- 3Strip paint, stains, and finishes when possible - lead-based paint requires hazardous waste handling
- 4Cut lumber to manageable lengths (4-8 feet) for efficient transport and processing
- 5Separate by wood type - softwood construction lumber from hardwood flooring/trim
- 6Remove composite materials, engineered lumber, and glue-laminated beams
- 7Check for contamination from oils, chemicals, or hazardous materials
- 8Sort by condition - reusable lumber separate from chipping/mulch material
- 9Bundle similar materials together for efficient processing
- 10Document wood source and age for proper disposal classification
- Wood recycling facilities specializing in construction lumber processing
- Mulch producers and landscape supply companies accepting clean wood
- Biomass power plants using wood waste for renewable energy generation
- Construction and demolition waste processing facilities with wood separation
- Architectural salvage operations for high-quality reusable lumber
- Habitat for Humanity ReStore accepting donations of usable building materials
- Specialized treated wood waste disposal facilities (for hazardous treated lumber)
- Local sawmills accepting clean lumber for processing into new products
- Community wood banks and lumber libraries for public access
- Urban lumber programs recovering trees from city removals and storm damage
- Furniture manufacturers accepting high-quality hardwood lumber
- Building material exchanges and construction waste diversion programs
- Farm and agricultural operations using wood for fencing and structures
- Educational institutions with woodworking and construction programs
- Deconstruction companies specializing in salvageable material recovery
- Municipal yard waste facilities with wood grinding capabilities
CRITICAL: Treated lumber contains arsenic, chromium, and other carcinogens - California classified pressure-treated wood as hazardous waste in 2021. Never burn treated wood as toxic fumes can cause cancer and death. CCA-treated lumber contains enough arsenic to kill 250 people per 12 feet. Always wear respiratory protection when cutting treated lumber. Pre-1978 painted wood may contain lead requiring specialized disposal.
Wood recycling offers significant environmental benefits by preventing deforestation of 14-16 trees per ton of recycled lumber while sequestering 1.85 tons of CO2 during wood's service life. Construction waste comprises 25-30% wood materials, representing massive recycling potential. Every ton recycled saves 3.3 cubic yards of landfill space and reduces methane emissions from decomposition. However, treated lumber creates severe environmental hazards - arsenic leaches for 50+ years, contaminating soil and groundwater at 100x safe drinking water levels. The contrast is stark: untreated wood recycling prevents habitat destruction and supports renewable resource cycles, while treated lumber requires hazardous waste protocols costing 10x standard disposal fees. Current US wood recycling rate of only 35% wastes billions in materials and carbon storage value.
- Architectural salvage for high-value lumber reuse in restoration projects
- Direct reuse in construction projects through material exchange programs
- DIY furniture and craft projects using reclaimed lumber
- Donation to woodworking schools, community workshops, or maker spaces
- On-site chipping for landscaping mulch and erosion control
- Biomass fuel for heating systems in appropriate applications
Accepted
- Clean untreated dimensional lumber from construction and demolition
- Hardwood flooring, trim, and millwork materials
- Unpainted wood siding, decking, and structural members
- Furniture-grade lumber and cabinet materials
- Clean wood pallets and shipping materials
- Tree branches and natural wood debris from land clearing
- Engineered lumber products (OSB, plywood) for appropriate facilities
Not Accepted
- Pressure-treated lumber (CCA, ACQ, or creosote-treated materials)
- Painted wood from pre-1978 construction (potential lead content)
- Wood contaminated with oils, chemicals, or hazardous substances
- Composite decking and synthetic lumber products
- Wood with embedded metals, wires, or non-removable hardware
- Laminated or glue-heavy engineered products at standard facilities
- Charred or fire-damaged wood with unknown chemical contamination
- Arsenic in CCA-treated lumber (carcinogenic and toxic to nervous system)
- Chromium compounds causing skin irritation and respiratory problems
- Creosote preservatives containing carcinogenic tar-based chemicals
- Lead-based paint on pre-1978 wood construction materials
- Pentachlorophenol wood treatments causing liver and kidney damage
How can I tell if lumber is treated and potentially hazardous?
Treated lumber often has greenish tint, stamps indicating treatment type (CCA, ACQ, PT), and may feel oily. When in doubt, assume it's treated - the health risks are too serious. Railroad ties and utility poles are always treated with toxic preservatives.
Is it safe to burn construction lumber in my fireplace?
Never burn treated lumber or painted wood - the toxic fumes can cause cancer, respiratory damage, and death. Only burn clean, untreated wood. When unsure about treatment, use safer disposal methods like recycling or landfilling.
What's the environmental impact of treated lumber disposal?
Treated lumber chemicals leach into soil and groundwater for decades, contaminating drinking water and harming wildlife. Proper disposal at hazardous waste facilities prevents this contamination, though it's more expensive than standard waste disposal.
Can I recycle painted wood from old houses?
Pre-1978 painted wood likely contains lead and requires hazardous waste disposal. Post-1978 painted wood may be accepted by some recyclers but significantly limits recycling options. Paint removal is often impractical for most applications.
What happens to recycled construction lumber?
Clean lumber becomes mulch, biomass fuel, or engineered wood products. High-quality pieces go to architectural salvage for reuse. The wood fiber retains value through multiple recycling cycles before final disposal.
How much treated lumber waste is generated annually?
Millions of tons of treated lumber reach end-of-life annually from decks, fences, and structures. Much ends up in landfills inappropriately due to lack of awareness about hazardous classification and proper disposal requirements.
Are newer wood treatments safer than older ones?
Post-2003 treatments (ACQ, CA-B) eliminated arsenic but still contain copper and other chemicals requiring careful handling. While somewhat safer than CCA, they're still classified as hazardous waste in some jurisdictions and shouldn't be burned.
What's the best way to handle a deck demolition project?
Assume all lumber is treated until proven otherwise. Separate treated materials for hazardous waste disposal, untreated for recycling. Use respiratory protection during demolition and never burn any materials on-site.
Can engineered lumber products like OSB be recycled?
Some facilities accept OSB and plywood for biomass fuel or composite manufacturing. However, glues and additives limit recycling options compared to solid lumber. Check with local facilities for specific acceptance criteria.
How does wood recycling compare economically to disposal?
Clean, high-grade lumber can generate revenue through salvage operations. Standard construction lumber often breaks even when avoiding disposal fees. Treated lumber disposal costs $100-300 per ton at hazardous waste facilities.
What are the health risks of working with treated lumber?
CCA-treated lumber contains arsenic (carcinogen), chromium (lung damage), and copper compounds. Exposure causes skin burns, respiratory problems, and cancer risk. Always wear N95+ respirators, gloves, and eye protection. Never eat or drink while handling treated lumber and shower after exposure.
How can I identify the age and treatment type of lumber?
Look for stamps indicating treatment (CCA, ACQ, CA-B, PT). Green tinting usually indicates copper-based treatments post-2003. Pre-2004 lumber may be CCA with arsenic. Railroad ties, utility poles, and marine pilings are always heavily treated with creosote or CCA.
What's the carbon footprint difference between recycling and disposal?
Wood recycling saves 3.3 tons CO2 equivalent per ton by avoiding landfill methane emissions and preventing deforestation. Burning clean wood for biomass fuel offsets 1.5 tons CO2 from fossil fuels. Landfilling wood wastes its carbon storage potential and generates methane over 50+ years.
Can I recycle lumber from water-damaged or flooded buildings?
Water-damaged lumber requires careful evaluation. If dried quickly without mold growth, it may be recyclable. However, flood-contaminated wood often contains bacteria, chemicals, and toxins requiring disposal as contaminated waste. Mold-affected lumber is typically not acceptable for recycling.