Does a raft slab need less reinforcement than a waffle slab?

Not necessarily less — reinforcement requirements genuinely depend on your specific soil conditions and building loads, not a general rule that one system automatically needs less steel than the other.

The two systems distribute reinforcement differently — a raft slab typically has a more uniform reinforcement pattern across a single thickened slab, while a waffle slab concentrates reinforcement within its ribbed beam structure.

Comparing reinforcement between the two systems in isolation isn’t genuinely meaningful — what matters is whether the specific system and its reinforcement design are appropriate for your actual site conditions.

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