The Ministry of Business, Innovation and Employment recently completed a public consultation on: Building for Climate Change: Transforming operational efficiency and reducing whole-of-life embodied carbon. As part of the submission process they asked “”What measures, if any, do you think should be put in place to reduce construction waste?”  The TAO Forum recognises that reducing construction and demolition waste and diverting it from landfill is a huge opportunity to reduce waste and made the following submission:

Tools to reduce construction waste

There are a range of established sustainability tools, standards and services available to large infrastructure projects to enable them to reduce construction waste:

  • Resource Efficiency in the Building and Related Industry (REBRI) resources and tools developed by Local Government, industry and the Building and Research Association of New Zealand (BRANZ).
  • Infrastructure Sustainability Council of Australia (ISCA) rating system for evaluating sustainability across the planning, design, construction and operational phases of infrastructure programs, projects, networks and assets.
  • Green Star ratings developed by the New Zealand Green Building Council, an internationally recognised system of rating tools that supports stakeholders in the property and construction sectors to design, construct and operate projects in a more sustainable, efficient and productive way.
  • Environmental Choice specifications developed by the New Zealand Ecolabelling Trust that assists waste collection providers and developers to track construction and demolition waste and its destinations.

These tools should be more integrated and promoted for use by designers, planners, government and construction sectors.

Targets for diversion

The TAO Forum recommends construction and demolition diversion targets (including monitoring and reporting) applied to all public sector construction projects and large-scale housing developments.

The following project Auckland’s City Rail Link adopted the Sustainability Council of Australia rating programme and used this to track and measure waste. The project generated 40,801 tonnes of waste with 29,956 tonnes diverted from landfill.

 Use of Site-Specific Waste Minimisation and Management Plans (SSWMMP)

A key measure to reduce construction waste is also the use of site-specific waste minimisation and management plans. A SSWMMP sets out the anticipated types of waste identifies what can be reduced, recovered or recycled and outlines how materials will be separated onsite. SSWMMPs should be adopted both for construction and de-construction projects.

In construction projects, one of the key barriers to diverting waste is to ensure that there is sufficient space on site to be able to store materials for recycling or reuse and to ensure that the necessary infrastructure is there e.g. cages and containers for separated materials. By requiring a SSWMMP as part of the planning or consent process this would ensure that this is taken into consideration when planning the set-up of the site.

Example: This video by Hamilton City Council shows how R J Alderton Builders are saving 75% of materials, which would previously have gone to landfill by separating materials on site.  Other examples of innovation in the construction and demolition sector can be seen here.

In demolition projects, a SSWMMP could identify opportunities to reuse materials e.g. fittings and fixtures which can be reused. It can also ensure that any hazardous materials are dealt with appropriately. Currently the waste industry experiences issues with building materials containing asbestos being sent to transfer stations and landfills without being identified as asbestos contaminated. LED lighting containing mercury is also sent to landfill, when it should be sent for recycling or treated as a hazardous waste as it contains mercury.

Example; Trow Group is a civil contracting and machinery hire company contracted by Auckland Council and Kāinga Ora to manage million-dollar projects across the Auckland and Waikato region. The company salvages and finds ways to reuse or recycle material from their building sites for schools, social housing, community centres and churches in NZ and the Pacific.

The TAO Forum recommends that a SSWMMP be mandatory for all government procurement of new buildings or renovation of existing buildings. This would include buildings such as schools, hospitals, government offices, state provided housing etc.

Example: The eight Councils of the Wellington Region recently proposed a new waste management bylaw for the purposes of promoting construction and demolition waste reduction.  While the threshold for requiring such a plan would vary across the Councils, Wellington City Council have proposed to regulate high-value building works ($2 million+) to submit a construction site and demolition waste management plan prior to the commencement of any building work.  Amongst other things, this plan is required to include detail of proposed methods of material reuse, recovery, recycling and disposal.

Require source separation of materials before landfilling

Another regulatory option could be to mandate the source separation of construction and demolition materials before being landfilled. Untreated timber, gib board and crushed concrete are materials common to many building sites which can all be recycled.

Example: Green Gorrilla construction and demolition materials recovery facility in Auckland is currently diverting 36.8% of their client’s commercial and industrial waste from landfill.

The waste disposal levy is being expanded to include construction and demolition fills. The revenue generated from the cost to dispose of construction wastes should be invested in  establishing construction and demolition materials recovery facilities to enable greater diversion from landfill. Investment in recovery and reuse facilities that stimulate local job opportunities and allow for localised processing and reuse of materials should be prioritised. Localised investment in resource recovery/reuse also presents an opportunity to reduce carbon emissions by minimising the need for raw/virgin material extraction and cartage of materials into or out of the district.

Ensuring building design allows for source separation and egress for collection vehicles

 The trend for high density housing and multi-story dwellings means the TAO Forum have started to see buildings being designed without sufficient space to minimise waste and permit recycling. For example, to minimise waste a building might need space for multiple source-separated bins including a rubbish bin, recycling bin, a cardboard cage and a receptacle for disposing of food waste. It is vital to ensure that in the building design there is sufficient space allowed for occupants of the building to separate materials. This is particularly important as separating organic waste for diversion is a key way to meet climate change targets.

Currently the building code (acceptable solutions G15) is limited to the design of the storage room and chutes but says very little about recycling. Given that it was last updated in 2010, the TAO Forum recommends it be updated to include the latest thinking around separating waste from recycling and diverting organic waste from landfill.

Example: Auckland Council regulates this within their Unitary Plan. This becomes a Resource Consent issue (as opposed to a Building Consent issue). This ensures the right kind of planning is incorporated early into the design of the development. Auckland Council’s guidelines can be viewed here.  

Equally, it is important to make sure there is space for collection vehicles to collect separated rubbish and recycling. We have seen innovation in road design, to make cycling safer.  The same design innovation should be applied to material separation and collection systems within and around buildings and supporting roading infrastructure to support waste minimisation outcomes.

Example: Dunedin City Council has been forced to create two inner city recycling hubs where residents can carry their recycling as there is limited space within existing building footprints for recycling to be collected onsite.

The TAO Forum recommends that central government give clearer and more detailed guidance to councils on how to regulate, minimise or avoid these issues.

In summary there is significant opportunity to reduce construction and demolition waste and the Ministry for Business, Innovation and Employment is encouraged to work closely with the Ministry of Environment, local government and industry to maximise these opportunities.