Dr Ben Redwood - CEO and Founder Mutu

Proposed Building for Climate Change Amendments to the Building Act 2004 and a number of media driven stories have dragged the construction sector into the spotlight when it comes to the waste the sector produces recently. Some figures suggest that the construction sector in Aotearoa is responsible for up to 50% of the waste that goes to landfill.

To counter this, there has been a shift by some organisations to increase the weighting of non-price criteria relating to sustainability in the tendering process. Auckland City Council recently announced their intentions to pursue social and sustainable outcomes whenever goods, services or works are procured and have indicated that some tenders will include a sustainability weighting as high as 15%.

So, what does this mean for the construction sector? In particular, what do organisations like Auckland City Council want contractors to provide to them to demonstrate that they are working towards sustainable outcomes? A general consensus in the sector is that developing and implementing a site waste minimization plan is a good place to start.

Developing a site waste minimization plan is crucial for promoting sustainable practices and reducing environmental impacts during construction projects. Some of the core aspects a good site waste minimization plan should focus on include:

Waste Assessment: Begin by conducting a waste assessment to understand the types and quantities of waste generated during each construction phase. Analyse the sources of waste and identify opportunities for reduction.

Set Targets and Objectives: Establish specific waste reduction targets and objectives for the project. These goals should be measurable, attainable, and aligned with sustainable construction principles.

Design for Reuse and Recycling: Encourage architects, engineers, and designers to prioritise materials that are easily reusable or recyclable, reducing the generation of waste from the outset.

Material Procurement: Work with suppliers to source materials with minimal packaging and those made from recycled content. Procure only the necessary quantities to avoid excess materials that may end up as waste.

On-Site Practices: Implement waste separation and recycling stations on-site to encourage workers to segregate materials properly. Train workers and subcontractors about waste management practices and the importance of waste minimization.

Reuse: Implement a system for sharing and reusing materials that are surplus with other sites thereby extending their lifecycle and reducing procurement of things that already exist.

Waste Diversion: Partner with local recycling facilities and waste management companies to ensure proper disposal and recycling of materials, diverting as much waste as possible from landfills.

Monitor and Review: Regularly monitor waste generation and progress toward waste reduction goals. Conduct periodic reviews to identify areas for improvement and implement necessary adjustments.

Documentation and Reporting: Keep detailed records of waste management efforts and their outcomes. Prepare reports to share with stakeholders and showcase the project's commitment to sustainability.

Continuous Improvement: Emphasise a culture of continuous improvement by learning from past projects and incorporating successful waste minimization practices into future construction endeavours.

Mutu is an organisation that works with construction companies to target the Reuse component of a site waste minimisation plan. Companies can use the Mutu app to list surplus materials, which are then made available to others who might have a use for them. When the materials are claimed, Mutu reports on these actions and provides real-time data on the impact - in terms of tonnes of waste and CO2 emissions redirected from landfill. So far Mutu has helped redirect more than 200 tonnes of surplus material back into new construction projects.

With the proposed changes to the Building Act, site waste minimisation plans will no longer just be a “nice to have”; and will become compulsory to obtain consent for any new construction or demolition project anywhere in Aotearoa.

By understanding these changes and by starting to put sustainability initiatives like Mutu in place, construction companies can put themselves in a position to not only comply with the new policy but also to drive a more sustainable Aotearoa.

You can find out more about Mutu here.