Permeable concrete paving is designed to reduce the volume of surface run-off, particularly in urban areas, and hence lower the risk of flooding.

By allowing rainwater to infiltrate into the ground across a wide area, rather than forcing into a few specific locations, this type of paving mimics natural drainage systems. It is often specified for car parks as part of a sustainable urban drainage system (SUDS).

The blocks are available in various finishes, including granite aggregate, aged, tumbled and textured, to match the aesthetics of the broader scheme. Some can also be machine laid.

Permeable concrete paving will typically be manufactured to BS EN 1338:2003 - Concrete block paving. The permeability of an installation, which is dependent on the laying pattern, is measured in litres per second per hectare.

Alternative hard surfaces that allow water to infiltrate into the soil include porous resin surfacing, porous asphalt and grass pavers.