Drainage Aggregate

Drainage Aggregate is crushed from natural rock, washed and screened to size. Used as drainage in trenches and over agg lines. For technical support including Test Results contact our Sales Team. Sizes available: 5mm, 7mm, 10mm, 20mm, 40mm

Available (inc GST): 25kg bag $10 · Loose (per tonne) $70 · 1 tonne bulka $92

What is drainage aggregate?

Drainage aggregate (also called drainage gravel) is crushed from natural rock, then washed and screened to a single size so water moves freely through the voids between stones. Because there are no fines it will not slump or hold water the way soil or road base does — which is exactly what you want around agg pipes, behind retaining walls and in soakage trenches.

Sizes and when to use them

• 5–7mm — bedding for agg lines and slotted pipe where a finer stone is specified.
• 10mm — general drainage around agg pipe, under slabs and in narrow trenches.
• 20mm — the standard choice for retaining wall backfill, French drains and soakage trenches.
• 40mm — high-flow applications, soakwells and larger rubble drains.

Not sure which size your job calls for? Read our guide to drainage aggregate and retaining wall backfill, or call the yard on 1300 935 483 — we supply test results on request.

How much do I need?

As a rule of thumb drainage aggregate weighs roughly 1.5 tonnes per cubic metre. Measure your trench length × width × depth in metres to get cubic metres, then multiply by 1.5 for tonnes. Our team can check your numbers before you order.

Delivery across Penrith & Western Sydney

Bulk delivery by the tonne across Penrith and Western Sydney on our own trucks, or pick up from the yard at 4 Harford Street, Jamisontown. 25kg bags are available for small jobs.