The parcel arrived with a two-metre fall across its length and a perched water table on the low side. The brief was a flat, buildable platform for a distribution shed, ready for a slab in under a month.

What we found on the walk

Old fill along the eastern third — the remains of a demolished shed nobody had recorded. Compacted differently from the natural ground, it would have shown up as differential settlement two winters after the slab went down.

What we did

We stripped and stockpiled the topsoil for reuse, dug out the old fill entirely and replaced it with graded material from the cut. Setting the platform level 40 cm lower than the original design let the cut and fill balance on the parcel: not one lorry of spoil left the site, and none had to be imported.

The perched water on the low side was intercepted with a French drain tied into the stormwater run we were already installing.

Handover

Platform to ±20 mm, compaction tested across a grid, and an as-built plan handed to the structural engineer. The slab went down eleven days later.