Recycled concrete aggregate (RCA) is exactly what it sounds like — old concrete from demolitions, crushed and screened to specific size grades. On Gold Coast residential and commercial work it does the same job as virgin quarry product at a lower price, with a fraction of the embodied carbon. Here's what each size is for.
RCA 5mm — fines for fine work
- Paver bedding (instead of brickies sand)
- Pipe bedding for stormwater and sewer
- Top dressing on pathways
- Base layer for synthetic turf
5mm is the fine end. Compacts tight, locks together, drains well. Don't use it where you need free drainage through the layer — go up to 10mm or 20mm for that.
RCA 10mm — the all-rounder
- Driveway base under concrete or pavers
- Shed slab base
- Path and footing base
- General-purpose hardstand
10mm is the most-ordered size for residential work. Compactable, stable, free-draining enough for most uses.
RCA 20mm — sub-base for slabs and roads
- Sub-base under residential slabs
- Driveway sub-base for heavier loads
- Working platform for site access
- Detention pit and basin base
20mm gives you a stable working platform that drains well. The go-to for slab sub-base on Gold Coast residential builds.
RCA 20-40mm — drainage and backfill
- Backfill behind retaining walls (with geofabric)
- Drainage trenches
- Sub-soil drainage layers
- Erosion control on sloped sites
Chunky and free-draining. Don't use as a driving surface — it doesn't compact tight enough.
Why use RCA instead of virgin quarry?
- Cheaper — typically $15–25/m³ less than equivalent virgin product
- Identical engineering performance for most applications
- Lower carbon footprint — diverts demolition waste from landfill
- Locally produced — short haulage from Gold Coast crushers
- Generally accepted under most council and engineering specs
We deliver RCA in tipper loads from our recycled crushers to anywhere on the Gold Coast or Brisbane. From $90/m³ depending on size and suburb. Call 0487 193 085 to order.
When to use virgin quarry instead
There are still cases where virgin product is required: certain RMS/Transport for NSW road specs, decorative aggregates where colour matters, and some structural concrete mixes specified by an engineer. For 90% of residential and small commercial work, RCA is the smarter choice.