The visible aggregate is only the surface course. The condition and design of the construction underneath it matter just as much to long-term performance.
Subgrade and sub-base: the natural ground and load-spreading foundation must be suitable for the site, expected use and drainage strategy.
Immediate substrate: the resin may be installed over a purpose-designed permeable base or, on suitable projects, over an existing sound hard surface prepared for overlay.
Resin-bound surface course: washed, graded, kiln-dried aggregate is mixed with the selected resin before being laid and trowelled.
Edge restraint: block, stone, metal or another suitable restraint contains the resin at lawns, planting, paths, walls and thresholds.
Drainage: a permeable resin surface only forms part of a fully permeable system when the underlying construction is also designed to accept and manage water.