Can patio slabs be installed directly on natural ground?

Natural ground is not generally suitable for the direct installation of patio slabs. This applies to both undisturbed ground and made ground, such as a lawn or garden area.

A load-bearing sub-base can be prepared with a modest amount of earthwork. First, set out the area for the future patio and remove the topsoil to a depth of 10 to 30 cm. The formation level is then prepared by levelling and grading the base of the excavation.

Where ground conditions require it, add and compact a crushed-stone layer. In many cases, however, this layer is not necessary.

Apply a 4 to 6 cm layer of grit to the formation level or the compacted crushed-stone layer. Carefully screed the fine crushed material evenly, then lay plastic grass reinforcement grids or gravel grids and fill them with grit or gravel.

This creates a load-bearing installation surface for suitable patio slabs with comparatively little earth movement. WARCO patio slabs made from rubber granules are one example of suitable patio slabs. WARCO patio slabs generally do not require lateral edge restraint.