What happens if my soil report comes back as Class E?

A Class E classification means highly reactive/extremely reactive soil, one of the more demanding classifications under AS 2870 — it genuinely means your foundation needs to be specifically designed to tolerate significant ground movement, but it doesn’t mean building isn’t possible.

Class E sites are commonly, successfully built on across Melbourne with appropriately designed foundation systems — often a more robust waffle slab design or, in some cases, deep foundations like bored piers — matched to what this classification genuinely requires.

A Class E result will generally mean somewhat higher foundation cost than a less reactive classification, reflecting the more substantial design required — a real, direct consequence of the classification, not a reason to be alarmed about buildability.

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