14 January 2026
Permeable, porous, resin bound, resin bonded, SuDS — the words around driveway drainage are confusingly close to each other. Here's a plain-English breakdown.
A permeable surface lets water pass through the surface itself, into a permeable sub-base, and then into the ground. Resin bound (the mixed-and-trowelled finish) is permeable. Loose gravel laid on a permeable sub-base is permeable. Permeable concrete blocks with wide joints are permeable.
A non-permeable surface — tarmac, concrete, traditional bedding-sand block paving — sheds water sideways. To be compliant for a new driveway, it needs to direct that water to a soakaway or planted area on the property's own land.
Resin bound versus resin bonded is the one that catches people out. "Bound" is what you want for a permeable, modern resin driveway. "Bonded" means a layer of resin spread on the surface with chippings scattered onto it — it looks cheaper, it isn't permeable, and it wears poorly. If a quote uses the word "bonded," check what's actually being offered.
