Specifying efficient use of materials and considering their impact from manufacture to disposal.
Construction and demolition produce large amounts of waste.
On this page
- costs of construction wastes
- statutory requirements
- waste diversion and rating tools
- ecolabel specification for construction and demolition waste management
Construction and demolition waste makes up 40–50% of New Zealand’s total waste going to landfill, according to government and council documents. Each home constructed generates an average of four tonnes of waste. An Auckland study found that construction waste by weight is made up of timber (20%), plasterboard (13%), packaging (5%), metal (5%) and other (45%).
Most of this dumping of construction waste is unnecessary – it has been demonstrated that simply by sorting waste, at least half of it could be diverted from landfills and cleanfills. Large volumes of waste also increase the costs of a project and its environmental impact.
Kāinga Ora has a target of diverting 80% of waste from landfill in its large development projects. It aims to reuse or recycle up to 80% of building materials (excluding contaminated materials). The target has been extended to include small to medium public housing developments in Auckland, with other regions due to follow.
Costs of construction wastes
Environmental costs from waste disposal include:
- limited reuse of landfill sites due to potential health hazards
- energy required in transportation
- pollution to land, air and water from heavy metals and toxic chemicals
- greenhouse gas emissions – emissions from landfills are estimated to make up 4% of New Zealand’s total emissions
- unsustainable depletion of resources.
Economic costs from waste disposal include:
- cost of operating and maintaining landfill sites
- cost of transporting waste to landfills
- loss of financial benefit from using recycled or salvaged materials.
Social costs from waste disposal include:
- noise, dust and traffic pollution to the community
- effects of hazardous or nuisance waste to workers on a building site and to the community.
The Building Act 2004 contains sustainability principles that the Ministry of Business, Innovation and Enterprise (MBIE) and building consent authorities (BCAs) must take account of under the Act. These include:
- the efficient and sustainable use of materials
- the reduction of waste during the construction process.
The Waste Management Act 2008 introduced a levy of $10 per tonne (excluding GST) on municipal landfill waste from 2009. This had little impact in the building industry because large quantities of waste from construction and demolition do not go to municipal landfills – they go to cleanfills and other sites – and were therefore never subject to the levy.
In July 2021, the Government began a process of increasing and expanding the cover of the waste disposal levy. The levy will be increased in stages until it reaches $60 per tonne at municipal landfills in July 2024.
The levy scheme is expanding to cover additional landfill types, including construction and demolition fills. Construction and demolition fill (class 2) now attracts a levy of $20 per tonne and this will rise to $30 per tonne by July 2024. Managed or controlled fill facilities (class 3 and 4) will see a levy of $10 per tonne from July 2023.
In December 2022, the Government announced proposed amendments to the Building Act that will include making it mandatory for a waste minimisation plan to be prepared for certain building or demolition work. A bill introducing the changes will be introduced to Parliament in 2023. The changes will be phased in over time.
Waste diversion and rating tools
The Homestar rating tool for residential buildings awards points for diverting waste from landfill. At least 50% can be diverted, and often 60–70% is achieved.
(The Green Star rating scheme for commercial buildings also rewards waste diversion. The New Zealand Green Building Council reports that some commercial projects have diverted 90% of building site waste.)
Ecolabel specification for construction and demolition waste management
The New Zealand Ecolabelling Trust (which administers Environmental Choice New Zealand) has developed a specification for construction and demolition waste management to help reduce the amount of waste going to landfills. It can be downloaded from this page.
The first company to achieve the ecolabel, Christchurch company Taggart, has shown it is possible to divert 70% to almost 100% of waste from landfill, even in its work demolishing the remains of the Tui stand at Lancaster Park.
Updated: 12 December 2022