Clearing construction debris

What builders leave behind

New-build plots often hide broken bricks, concrete washings, plaster, cement bags, offcuts of timber and plastic just under a thin skim of soil. Grass grows over it for a few weeks and then browns in the first dry spell, because there is no soil for roots to reach water.

Find it

• Push a steel rod or a long screwdriver into the ground on a grid. Where it stops short, dig and look.
• Pale, gray patches of soil often mark cement or lime washings, which also raise pH sharply.
• Check around foundations, paths and where the skip, mixer and pallets stood.

Remove it

Dig out the debris, not just the surface layer, and remove it from site. Clean hardcore can sometimes be reused under paths but not under lawn. Where cement washings were dumped, replace the affected soil and run a pH test.

Next: break up the compacted subsoil, then bring in topsoil.