Can a raft slab support a two-storey home?

Yes, provided the design genuinely accounts for the additional loads a two-storey structure introduces — raft slabs are used for both single and double-storey homes, with the specific reinforcement and thickness scaled to the actual loads involved.

The key factor is proper engineering design matched to your specific building’s loads and your site’s soil conditions, not the number of storeys alone determining suitability in isolation.

If you’re planning a two-storey build, or considering adding a storey in future, telling your engineer this upfront ensures your raft slab genuinely accounts for those loads from the outset.

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