Greening construction: utilising the potential of building waste

Greening construction: utilising the potential of building waste

Today we produce more than one-and-a-half tonnes of waste per person per year. And a massive 40% of this waste comes from construction and demolition, with up to 80% of construction waste made up of discarded materials that have the potential to be re-used or recycled. In short, this waste has wasted potential.

Not only is it beneficial to minimise construction waste; it is also necessary. As we witness an increase in green projects and initiatives around the world, the issue of how this can be done becomes increasingly apparent.

A report from the Australian Government entitled Construction and Demolition Waste Guide – Recycling and Re-use Across the Supply Chain identifies a number of materials that often wind up as construction and demolition waste. Concrete, bricks, asphalt, different varieties of metal, timber, plastics, plasterboard, rock, excavation stone, soil and sand are just some of the materials resigned to this fate.

Lately, a number of projects and initiatives have begun to address this wasted waste potential. The most recent of these is the Australian company Resource which will be able to turn non-recyclable commercial and industrial waste into alternative fuel.

Once completed, the ResourceCo. plant at Sydney’s Wetherill Park will be able to turn non-recyclable commercial and industrial waste into a type of alternative fuel. Not only would this constitute a beneficial re-use of underutilised materials, the resulting fuel – a solid fuel known as Processed Engineered Fuel (PEF) – would reduce the carbon profile of cement.

Due to be operational by March 2018, the plant is expected to turn 150,000 tonnes of waste a year into PEF. In doing so, it will reduce greenhouse gas emissions, avoid soil and water contamination and conserve resources.

Another local example of a construction waste initiative is the Green Building Council of Australia’s (GBCA) Green Star ratings system, which encourages the minimisation of construction and demolition waste. The rating system consists of a ‘Construction and Demolition Waste’ credit which aims to encourage and reward management practices that minimise the amount of construction and demolition waste from base building and/or interior fitout works that is disposed to landfill.

In the Netherlands a house in Rotterdam house has been built using bricks from rubble.

In the Netherlands a house in Rotterdam house has been built using bricks from rubble.

One of these is a house in Rotterdam designed by Dutch architecture firm Architectuur Maken. The house was built using bricks made from rubble in an effort to divert construction waste from landfill and reduce the demand for virgin materials – in the EU, construction waste accounts for one-third of overall waste. The bricks were sourced from StoneCycling, a company specialising in bricks made from recycled materials with 15 tonnes of compacted industrial waste used to build the tall, skinny house.

Yet another example is a California-based company called Watershed Materials who have developed technology to repurpose excavated waste on building sites. The technology allows the excavated waste to be turned into building materials, therefore eliminating the problem of waste disposal and bringing the materials full-circle in a process of re-use.

Watershed-Materials

Watershed recycling machinery

The company’s onsite pop-up plant repurposes excavated material right at the job site to create concrete masonry units (CMUs) for use in the development. It also helps the environment by eliminating truck traffic, reusing waste, and reducing the need for imported materials.

With these examples in mind, it’s clear that people are recognising the potential of what was previously considered un-useable. As more initiatives continue to emerge, the benefits of recycling and re-purposing construction materials will only become more apparent.

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