Does a house slab need a damp-proof membrane?

Yes — a damp-proof membrane (typically a plastic vapour barrier laid before pouring) is standard, genuine practice for slab-on-ground construction, managing moisture movement from the ground into your slab and, ultimately, your home.

This is a compliance-relevant requirement under the National Construction Code, not an optional extra — a properly built house slab includes this as standard, not something to skip to save cost.

Your builder or contractor includes this as part of correctly executed slab construction — worth confirming it’s genuinely included if you’re ever unsure about your specific quote’s scope.

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