Resin-bound paving is a mixture of aggregate stones and resin used to pave footpaths, driveways, etc. It is a kind of permeable paving solution. It is a flexible surfacing material, so is resistant to cracking. The system is mixed on site and cold applied, using a high-quality clear UV resistant resin binder to coat the aggregate particles prior to laying. Unlike resin-bonded surfacing, where a thin layer of resin is applied to the surface and then the aggregate scattered on top (which can then become loose over time and is impermeable), resin and aggregates are thoroughly mixed together prior to laying, ensuring that the aggregate is completely coated and so providing a totally bound surface. As a result, a resin-bound surface is more durable and requires less maintenance – it needs to be swept or power washed at least twice a year, to avoid the build-up of detritus and prevent the growth of moss or algae. UV resin-bound paving is a fully permeable paving solution which allows water to freely drain through the surface. Meeting the requirements of Sustainable urban drainage systems (SUDS) standards, this helps to prevent standing water and largely eliminates surface water runoff. This also mitigates the need for planning permission when installing a resin driveway as they are permeable.. Resin-bound surfacing conforms to the guidance notes set out by the Resin Flooring Association (FeRFA). The quality of the resin-bound surfacing is dependent on a variety of factors. The UV 2 part polyurethane resin should always be sourced from a manufacturer who can demonstrate that they have BS EN UKAS ISO9001 quality management standards (available information on the FeRFA website). All companies conforming to this will be able to provide documentation on request. The resin-bound aggregate mix will generally be a mix of natural aggregates that must be kiln dried to prevent moisture coming in contact with polyurethanes and causing discolouration and poor performance. The UV resin sourced should be a two-part, quality-controlled polyurethane or similar with the activator added during the manufacturing process to eradicate mistakes on site made by operatives who are not qualified chemists. Too much activator or too little can affect the performance of the product. The activator has a high risk to health and safety and serious consideration must be given when handling it. The ratio of resin to aggregate should be at the optimal amount (7% resin to aggregate) depending on