♻️ Zero-Waste Construction: Material Flow Accounting Lab

About this simulation

Material flow accounting (MFA) tracks every tonne that enters a construction site — timber, concrete, plasterboard, metal — and follows it back out again: into the finished building, into a skip bound for landfill, into a recycling facility, or straight back into reuse on another job. This lab animates that accounting as a live 3D flow diagram: particle streams carry material from the site hub out to three destinations, and their thickness scales with the tonnage actually moving along each path.

How it works

• Diversion rate — the share of total site waste that is kept out of landfill through reuse or recycling, the core KPI in most zero-waste-to-landfill targets (often 90%+ for certified schemes).
• Reuse vs. recycle mix — reuse (reclaimed bricks, timber, fittings) avoids re-processing entirely and saves more embodied carbon per tonne than recycling, which still requires energy to reprocess material into new stock.
• Truck trips — every tonne sent to landfill instead of a local reuse/recycling loop needs hauling, usually over a longer distance to reach permitted disposal sites, adding diesel-truck emissions on top of the waste itself.
• Logistics CO₂e — modelled from truck trips avoided × haul distance, showing why diversion strategy and site logistics are accounted for together, not separately.

Controls

• Site throughput — total material moving through the site per day (tonnes).
• Waste diverted from landfill — the diversion rate applied to that throughput.
• Reuse vs. recycle mix — how the diverted material splits between direct reuse and recycling.
• Haul distance to landfill — round-trip distance used to estimate avoided logistics emissions.
• ↺ Reset flow — restarts the particle streams. Drag to rotate, scroll to zoom.

Did you know?

Construction, demolition and excavation waste is one of the largest waste streams by mass in most developed economies — in the UK it is around a third of all waste generated — which is why material flow accounting has become a standard tool for contractors chasing BREEAM, LEED, or zero-waste-to-landfill certification.