New turf should never be laid directly over an old lawn, even with a thin layer of soil on top of the old grass. The surface will act as a barrier and prevent the new grass roots from growing deep into the ground.

Existing turf should be removed by slicing beneath the grass with a spade, or for larger areas, a purpose-designed turf cutter can be hired.

The soil needs to be turned over to a depth of at least 15 cm (6 inches) using a spade or powered cultivator. Clear the surface of stones, weed, old turf and other debris.