AS/NZS 3500 is the standard behind the pipes — the water coming in, the waste going out, and the stormwater carried away. Two parts of it show up clearly on a new-home inspection: the drains under your slab, and the stormwater around your home.
What AS/NZS 3500 actually means
AS/NZS 3500 is the national plumbing and drainage series, covering water services, sanitary plumbing and drainage, and stormwater drainage. It sets how these systems should be installed to work reliably and protect health and the building.
Where it applies in your new home
The drainage cast into your slab before the pour — the "drains" stage in Queensland — is governed here, as is the stormwater system that must carry roof and surface water to a legal point of discharge with the correct fall. Getting the falls right is what stops water pooling against the slab.
What VG Inspect checks against it
At pre-pour, an inspector confirms the under-slab drains are in place and match the plan before concrete covers them. At PCI, the checks turn to stormwater and site drainage — downpipe connections, and finished-ground levels that fall away from the building. Backfall in a line or levels that trap water against the slab are recognised findings. Compliance certification remains the licensed plumber's responsibility.
What it does and doesn't cover
AS/NZS 3500 covers plumbing and drainage. Wet-area waterproofing is covered by AS 3740, gas by AS/NZS 5601, and electrical by AS/NZS 3000.
A VG Inspect QBCC-licensed inspector (QBCC Licence 1318443) checks under-slab drains at pre-pour and site drainage at PCI. Call 07 3180 8041 or book an inspection online.