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-up ground, such as a lawn or garden area.
A load-bearing sub-base can be prepared with relatively limited groundworks. First, the area for the future patio is set out and the topsoil is removed to a depth of 10 to 30 cm. The formation level is then prepared by levelling and grading the base of the excavated area.
If ground conditions require it, an aggregate layer is added and compacted. In many cases, however, this aggregate layer is not necessary. A 4 to 6 cm layer of chippings is applied over the formation level or compacted aggregate layer. This fine crushed aggregate is carefully and evenly screeded.
Plastic grass grids or gravel grids are then laid on top and filled with chippings or gravel. This creates a load-bearing installation surface for suitable patio slabs with comparatively little earthmoving. Patio slabs made from rubber granules are an example of suitable patio slabs. For these patio slabs, a lateral edge restraint can generally be omitted.