What materials can be recycled?

Most construction and demolition materials that can usually be reused and recycled.

Resources for material reuse and recycling

'Building without waste' (PDF) - Hamilton City Council

Hamilton City Council has outlined a list of priority materials and options for waste minimisation. Materials listed as forbidden for landfill or cleanfill MUST NOT be directed to these destinations. Any materials listed for recovery, recycling or reuse should be handled in a way that maintains their use integrity and value.

Quick reference guide for materials and reuse and recycling

Right-click image to select 'open image in a new tab' to view larger.

Construction waste reduction plan - a guide (PDF) - New Plymouth District Council

Minimising construction and demolition waste - Auckland Council

Construction and Demolition Waste - Nelson City Council

Suggestions for material reuse and recycling

We outline a number of common construction and demolition materials below and outline some suggestion for their review or more generally what to do about them. Use the BRANZ Resource Recovery Map for identifying resource recovery options and services in your local area.

For some sorted materials, waste collectors will remove filled skips and containers at no charge and may take co-mingled materials for off-site separation for a small fee.

Asphalt

sort by type for milling and recycling
break up and reuse on site for temporary road construction or hardfill

Brick

whole bricks set with lime-based mortar - reuse in fences, landscaping and construction
whole bricks set with concrete – clean and reuse or recycle
broken bricks - crush for use as landscape over, sub-base material or hardfill

Cardboard and paper

separate for recovery and recycling into new products – use local kerbside collection and/or commercial collection resource recovery services

Concrete and masonry

use crushed concrete aggregate anywhere natural aggregate is currently used, including:
- loose on driveways, for unsealed hard stand and in landscaping
- as a base course for footpaths, roading, driveways and other asphalted or sealed surfaces
- as a base course under building foundations in civil works such as stopbanks, earth bunds, soakage pits, drainage channels and beds for pipe works and cabling
cast-in-place and precast concrete - recycle or reuse for stabilising slopes, river banks and foreshores
concrete/masonry block not filled with concrete - reuse
concrete/masonry block filled with concrete - recycle
paving stones - reuse/recycle
tiles/slates - reuse/recycle
pipes, masonry service structures - reuse/recycle

Glass

sheet glass - recycle

Hazardous materials

paints, solvents, asbestos and other hazardous fluids – compliant and safe removal, storage, transportation and disposal at a dedicated facility. Contact WorkSafe or your local council for guidance.
materials with lead-based finishes – compliant and safe removal, storage, transportation and disposal at a dedicated facility. Contact WorkSafe or your local council for guidance.

In the interests of health and safety, you should check the removal and disposal requirements of hazardous materials with WorkSafe and your local council. Some manufacturers have take-back schemes for paint (such as the PaintWise scheme from Resene).

Metal

aluminium (soffit, cladding, cappings, flashing) - reuse or recycle
cast iron - recycle
chain link fencing - reuse or recycle
copper (flashing, wiring, plumbing) - reuse or recycle
drink and food cans - recycle
interior steel wall studs - recycle
lead (piping, plumbing, flashing) - recycle
reinforcing steel (rebar) - recycle (usually embedded in concrete so not reusable)
steel and zinc (roofing, cladding flashing) - reuse/recycle
structural steel - reuse (including I-beams, square tubing, pipe and channel steel), otherwise recycle
miscellaneous steel - reuse/recycle
miscellaneous other metals - reuse/recycle

Plastics

packaging, pipe off-cuts, expanded polystyrene block off-cuts, buckets - separate by type (all are labelled) for recycling into new plastics. Plastics with the numbers 1, 2 and 5 are generally recyclable, numbers 3, 4 and 6 are not
some manufacturers of polystyrene products such as insulation offer recycling services for their customers

Plasterboard

Once recycled plasterboard is crushed, the gypsum can be sold as a powder (with or without the paper) or moulded into pellets. Gypsum can be:

used as soil and compost conditioner and for other agricultural applications
composted with other green waste
combined with sawdust and wood shavings for animal bedding, because it absorbs moisture
reused in the plasterboard manufacturing process (depending on the manufacturer's specifications for gypsum quality)
used in the cement-making process (virgin gypsum is currently added to the clinker to control the setting time
used for drying sludge from municipal and industrial wastewater treatment plants because of its moisture-absorbing characteristics
used to settle dirt and clay materials in turbid water
used to absorb grease spills

Soil

retain and replaced after construction so that existing nutrients can be returned back to the site. Check with your local council for any requirements.

Timber

includes treated and untreated timber, hardwood, native timber, demolition, off-cuts, framing, cladding, interior fittings and linings, engineered timber products (MDF, fibre board, particle board etc.), joinery, panels, lengths, pallets and packaging
untreated timber - reuse, separate all types of untreated timber without finishing (paint, varnish etc.) that is not good enough for salvage (under 600 mm or damaged) burn for fuel, mulch or recycle lengths greater than 0.6 metres
treated timber - reuse, lengths greater than 0.6 metres (or 450 mm where this is the spacing of structural framing)
engineered timber products, trellis and other timber products - reuse or recycle panels of greater than 0.5 square metres
treated or untreated heavy timbers/posts - reuse

Vegetation

trees - remove and replant specimen trees
vegetation - mulch or chip for use a ground cover, mulch, compost

Managing liquid wastes

Liquid wastes from construction sites are a significant pollution problem and should be minimised.

Mud and silt from uncontrolled run-off is the most common pollutant, but adverse weather may also result in ruining or relocation of materials and wastes.

Construction site pollutants and their causes are:

silt/mud - run-off from cut and fill areas
oil/fuels/paints - spills and leaks
cement/concrete - wash-off from formwork and machinery
detergent/degreasers - wash-off from formwork.

Don't mix the drains!

stormwater drains are for clean rainwater only, as it goes directly into watercourses: streams, lakes, harbours and beaches. Stormwater is untreated. Discharging pollutants into stormwater drains is illegal, unless you have resource consent or it is a permitted activity. Stormwater can be contaminated by particles and chemicals that leach from C&D waste.
wastewater drains or sewers are for blackwater (i.e. sewage) and trade wastes only. It is treated before going into watercourses

Make sure all site workers know the difference. Spills can be very costly for the polluter.

Dealing with liquid pollution

have a dedicated wash-down area
use bunds or drip trays to prevent leak and spill contamination
use gravel areas, silt fences, swales or ponds for silt containment
install oil and grease interceptors
make sure paint left-overs are dry before disposing with solid wastes

Plan ahead

draw up a drainage plan for your site
ensure that any stored liquid materials are safe and secure
have a spill kit for fixing and effectively dealing with spills on site
write a spill procedure plan to deal with accidents
have regular inspections and maintenance

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Updated: 5 September 2025