What a waste!

This Issue This is a part of the Cleaning up feature

By - , Build 164

The building and construction industry has a shocking record when cleaning up after itself. It contributes more to New Zealand’s burgeoning waste stream than every other industrial, commercial and household activity combined.

CONSTRUCTION AND DEMOLITION WASTE is a complex mix of mostly concrete, plasterboard, timber, steel, brick and glass. It makes up approximately 26%, or 820,560 tonnes, of waste to landfill and almost all of the 3.7 million tonnes of waste sent to cleanfill every year.

Concerning levels of waste

While a large proportion of this comes from commercial building, it’s far from a solely commercial problem. Research indicates that every new residential build sends on average 4 tonnes of construction waste to landfill.

Waste at these levels should be cause for concern, especially as the thriving commercial property market and unprecedented demand for new homes sends building activity to record highs. Yet the industry isn’t entirely sitting on its hands.

Some initiatives try to tackle problem

Initiatives such as Resource Efficiency in the Building and Related Industries (REBRI) and the New Zealand Green Building Council’s (NZGBC) rating tools go some way toward raising awareness within the industry.

Andrew Eagles, Chief Executive of the New Zealand Green Building Council, says the Homestar rating tool is confirmed for 20,000 new Auckland builds. It can facilitate the reduction of construction waste by up to 70%, potentially diverting 50,000 tonnes of waste from landfill. The Green Star Interiors tool shaved $200,000 off the cost of the Auckland Council building refit by diverting hundreds of tonnes of waste from landfill and recycling it back into construction materials.

Incentives needed to reduce waste

There are numerous examples like these of what the industry can do, but for the overwhelming majority of builds, it seems it’s business, or rather landfill, as usual. Eagles says the problem boils down to motivation.

‘If you’re under pressure to build as many homes as you can and it only costs $10 per tonne to chuck your waste into landfill, what would you do?’ he asks. ‘There’s little guidance and no incentives or encouragement to do anything else.’

A 2014 review by the Ministry for the Environment recommended substantial increases to the waste disposal levy as a means to incentivise waste reduction and help meet the rising cost of landfills. It proposed increasing the levy from its $10 default to $100 or more. At the time, more than 80% of WasteMINZ members supported the move, but the recommendations have yet to be acted upon.

Lack of clarity – serious goal needed

With no meaningful targets, Eagles has gone on record to challenge the building industry to cut a third of all construction waste by 2020.

‘We need a serious waste-reduction goal in this country, but the lack of ambition is astronomical,’ he says. ‘Politicians think they need to tread carefully because the construction companies don’t want it. That’s not true. They want clarity. Instead, we spend millions of dollars to fill our country up with landfill. It’s a tragic waste of resources.’

Local practices lag behind overseas

Ironically, decades of international evidence and home-grown pilot projects suggest it would be relatively easy and inexpensive to slash construction waste.

For instance, in European countries, it’s common practice to sort waste, a simple process that diverts at least half of the construction waste stream away from landfills and cleanfills and can save even modest-sized projects significant dumping fees. Most countries require it by law.

‘New Zealand is still in its infancy when it comes to waste reduction in the construction and demolition sector,’ says Jeff Seadon, waste minimisation researcher and Senior Lecturer in the Department of Built Environment Engineering at AUT.

‘Most of the dumping of construction waste in this country is unnecessary. While China and Australia have similar levels of waste to New Zealand, it can be quite low in other countries.

‘For example, Vancouver has taken a strong line on reducing demolition waste. Demolition of pre-1940 homes must comply with the Green Demolition Bylaw where 75% of demolition materials must be reused or recycled. In 2015, Vancouver approved expanding the bylaw to include all homes by 2018.’

The UK undertook similarly ambitious waste reforms, with the full support of the construction industry.

Focus by government and industry needed

Perhaps the greatest enabler of change in recent years is the Waste Minimisation Act 2008. A wide-reaching Act, it aims to encourage waste minimisation and decrease waste disposal across many areas of the economy. While it falls short of mandating waste targets, it established a framework to incentivise a range of voluntary reduction schemes.

‘So far, the construction and demolition sector has not engaged in trying to reduce waste. And the government, so far, has not actively sought to focus on this waste stream,’ says Seadon.

The problem isn’t limited to the construction industry. Across all waste streams, lack of action has left the rate of waste disposal to increase each year, meaning the country now dumps 40% more waste than it did when the Waste Minimisation Act came into force.

‘The effectiveness of waste minimisation, in general, in New Zealand is minimal,’ Seadon says. ‘It will take a focus by central and local government and the industry to improve the situation. The industry, in particular, needs to step up to the challenge.’

However, some organisations aren’t content to wait for widespread engagement or for the government to step in and regulate the issue. They are already showing that it is possible to achieve significant voluntary waste reduction and to do it in a sustainable and profitable way.

Product stewardship schemes

Among its changes, the Waste Minimisation Act introduced product stewardship into the regulatory framework. A common element of waste minimisation strategies overseas, product stewardship pushes responsibility for waste back to those involved with waste-creating products. Rather than the dump-and-forget approach of landfill, product stewardship means whoever designs, manufactures, sells or uses a product must deal with its impact on the environment.

There are currently 13 accredited voluntary product stewardship schemes operating in New Zealand, including Resene’s well known PaintWise recycling programme and Envirocon, which diverts waste construction concrete from landfill.

Upcycled concrete a win-win

‘The New Zealand construction industry generates an estimated 270,000 tonnes of surplus wet concrete that goes to landfill every year,’ says Jack Bright, Manager of the Envirocon Product Stewardship Scheme. ‘It’s perfectly good concrete, and if collected in time and handled correctly, it can be recreated – upcycled – into valuable precast concrete products.’

Bright’s proposal to form a concrete stewardship scheme received a very enthusiastic response from concrete manufacturers.

‘Allied Concrete and Stevenson Concrete were especially supportive, and we’ve expanded our collection activities to the point where we now divert 20,000 tonnes of concrete from landfill every year,’ he says.

That’s still well shy of the 270,000-tonne national total, but Envirocon has plans to reach 80% of New Zealand’s concrete manufacturers and divert more than 80,000 tonnes per year by 2022.

‘With R&D assistance from Callaghan Innovation and funding from the Waste Minimisation Fund, we developed technology that allows us to move the collection of concrete into the concrete batching plant. This means we can collect larger quantities from further afield and process it more efficiently,’ he says.

Two of the products made with the scheme’s upcycled concrete – Interbloc, a modular wall system, and Stonebloc, a fast-build retaining wall – are sold to Australia.

‘The uptake from the industry has been very good, but I think it boils down to the fact we save them and their customers money – we convert a waste stream into a revenue stream,’ he says.

AUT’s Jeff Seadon agrees. ‘If the construction industry wants to increase its profits while giving customers a better deal, waste is a good place to start looking.’

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