These two types of resin driveways are often confused. Often, I hear homeowners ask, can I have a resin bonded driveway installed, while in essence, they’re looking for a resin bounded driveway. This begs the question, is a resin bound and a resin bonded driveway the same?
Honestly, they are not! They are in fact uniquely different.
A Resin bound surfacing provides an environmentally friendly, water-permeable surface when laid on any stable sub-base such as asphalt or concrete surface. Essentially, the resin-bound mixture has open voids across the surface, allowing surface runoff to filter through the structure and also allows for free air flow.
Resin driveways are most ideal for making a permeable system for paths, driveways, tree pits and areas prone to water puddling. The super-smooth resin bound drives are surfacing, with no loose stones, is suitable for wheelchair access and is tough enough to withstand pressure washing.
By contrast, resin bonded driveway surfacing is a non-permeable matrix and must be laid on a non-porous fine wearing course asphalt or concrete base. With resin bonded surfacing, ACO drains and soak ways must be installed to prevent pesky surface run-off which could lead to flooding.
WHAT IS A RESIN BOUND (OR “TROWELED”) SURFACING?
Resin bound driveway surfacing is made from a blend of quartzite, shingle, or crushed granite smoothly coated with a clear UV-stable resin. A force-action mix process is used to form a cold-pour mixture of aggregate particles completely coated in resin.
The cold-pour mixture is then poured on a newly placed or existing stable sub-base and is hand-troweled to form a smooth, porous surface with no loose stones. It is recommended that the resin bound driveway surface be laid to a minimum depth of 15mm for a patio, footpath, pool surround, or terrace and 18mm for car parks and driveways.
A resin bound driveway is, therefore, characteristically:
• smooth surface that allows water to sip in hence allowing for SUDs compliance.
WHAT IS RESIN BONDED (OR “SCATTERCOAT”) SURFACING?
On the other hand, resin bonded drives surfacing is laid by sprinkling loose aggregate onto the resin. A layer of UV stable resin is first laid on a stable surface, before loose aggregates such as shingles, crushed granite or quartzite is splayed on the resin layer.
It’s a great, low-cost option for re-development projects or for giving a project an instant facelift. However, due to the continuous resin layer, resin bonded drives are not permeable, meaning that water will flow off your driveway. This may escalate the flooding menace when largely used in urban developments.
When improperly done, resin bonded driveway surfacing is not as durable as resin bound paving. Why? Well, majorly because the bonded aggregate particles may loosen over time due to their stand-alone course finishing. Similarly, water puddles forming on the surface will leave chemical deposits on the surface, ultimately, deteriorating the chemical composition of resin.
Depending on the aggregate size [1-3mm], the depth is generally 3mm. The resin bonded driveways are characteristically:
• Have a rough surface finishing
• Non-compliant with SUDs regulations
PREPARATION AND SUITABLE BASES FOR RESIN BOUND AND RESIN BONDED DRIVES
Resin bound and resin bonded driveways can be placed on multiple existing driveway surfacing. The surface should be dry and clear of dust and other loose materials. Some of the surfaces where resin bound and resin bonded paving can be laid over include:
• Grid structures: the resin drives can be laid directly onto the compacted stone that has been in-filled with gravel.
• Crushed Rock: resin bound driveways can be laid on crushed rock especially if the walkway will have low pedestrian traffic and no vehicular access.
• Asphalt (Tarmac): Resin bound driveways with moderate vehicular access can be laid on an existing or a newly installed asphalt surface. The asphalt surface should be structurally sound and crack free.
• Concrete Surface: Resin bound or resin bonded driveway can be laid on a structurally sound and crack free concrete base that has been thoroughly cleaned and primed. In the case of a new concrete surfacing, a minimum of 7 days is recommended before installation of resin driveway atop.