When laying a resin bound surface, the base, or substrate, is essential in providing the strength and load-bearing capacity of the pavement, as such, the depth of the base will depend on the type of substrate being used and the expected traffic that the surface will be exposed to.
Resin bound paving is ideal for overlaying existing, ‘tired looking’ surfaces though it is essential that the substrate is sound, contamination free and able to withstand expected loads. This is of fundamental importance to a successful installation of resin bound surfacing, any weakness in the substrate could result in failures, such as reflective cracking, in the finished surface.
New areas intended for overlaying with resin bound paving should ideally be constructed as part of a fully sustainable drainage system (SuDS); where surface water can permeate through to the soil. We recommend that a sub-base layer of Type 1 hardcore is compacted to a depth range of 50-100mm, for pedestrian use and between 100-200mm, for domestic driveways. This can then be topped with open-textured asphalt of between 40mm-50mm depending on expected traffic. Due to the permeable properties of resin bound paving, new asphalt does not have to be left for any specific period to allow the migration of light oils. It is advised that the asphalt should be left slightly open-textured to be fully permeable, this will also promote greater adhesion with the resin bound surface. Once the base is ready, a well-compacted layer of the combined aggregate and resin can be applied at a minimum of 12mm for pedestrian areas and 18mm for driveways.
Where it is not possible to have a fully permeable surface, the pavement should be constructed to withstand the expected loads using pavement quality concrete or asphalt to recognised national standards. Because water will drain through the resin bound surface course, drainage measures will need to be constructed in the impermeable substrate to handle run-off. External concrete should ideally be finished as tamped or combed and left for a minimum of 7 days to allow surface drying, it is recommended to be laid at a depth of 75-200mm depending on the application.
For more information on recommended base build up please follow this link.
If you would like to learn more about the application of resin bound systems, Adbruf has a monthly training course where we can offer in-depth knowledge of how to prepare a surface ready for installation, awareness of the issues that you may face when approaching an installation and how best to deal with them.
Find additional training details here