Precycle: sorting building waste before it gets contaminated
A South Australian circular economy case study Rawtec worked on. 2019. The original is on the Green Industries SA website.
Summary published
A single skip bin on a building site collects everything mixed together. Business as usual on a residential build diverts about 10% from landfill.
Precycle collects materials at set stages during construction, while they are still clean and separated, before the next trade contaminates them.
Landfill diversion went from 10% to 76%.
Landfill diversion, against 10% business as usual
Skip bins per house
Waste volume per house
CO2 avoided per site
What the trial showed
Fewer bins, more recovered, and the environmental numbers
Skip bins per house fell from 3.8 to 1.1 and waste volume from 15 to 4.5 cubic metres. Landfill diversion rose from 10% to 76%. The service runs across six stages with pick-up on demand within 48 hours, and material is checked both at collection and at unloading.
1.4 tonnes of CO2 avoided, 19.7 gigajoules of energy saved and 4.1 kilolitres of water saved. Across ten houses that is roughly the annual emissions of 3.1 cars and the annual electricity of 3.8 households.
Cost, market size and the trial partner
Multiple skip bin removals cost more than staged collection. Site safety improves, illegal dumping drops, and the material is worth something because it is clean.
South Australia builds between 8,000 and 12,000 homes annually. A typical residential project runs 12 to 18 weeks.
The builder reported environmental benefits plus better site amenity and material management.
What it depends on
The model only works if recycling outlets will take clean, sorted streams.
One bin for everything is easier. Staged collection needs the builder to prioritise the cost saving over the convenience.
The service started with a 150 tonne a year limit, later removed. The case study suggests expanding across the South Australian construction sector and setting up a resource bank for reusable materials.
Related reports
Other pilots and case studies.
The full case study covers the six collection stages.
Working on something like this?
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