Resin bonded and bound Gravelcoat surfacing systems are pretty durable materials but they can only be applied on certain surfaces and substrates.

Gravelcoat resin bonded and bound surfacing systems can bond to an existing surface of tarmac, asphalt, concrete or other monolithic material that has been cleaned and prepared. The existing surface should be in good condition as any system applied is dependent on its foundations.

It is important that the surface is cleaned properly with all loose materials and dust removed and sealed if necessary. Any contaminates such as oil or traffic film will require removal with a suitable de-greaser to ensure the resin can bond fully to the base. Fully remove any Algae or fungus that may be present.

Any damaged areas or cracks will require treatment and repair prior to the application of resin. Attention to how level the surface is that the resin will applied to is important. If the level varies, more resin and aggregate will be required to create a level surface. This can raise the cost of the scheme given that more materials are required and care will be needed at the estimation stage.

The base should be suitable for the loads it’s expected to carry once the chosen Gravelcoat resin system is applied. There is no preferred base as this can vary depending on the system used, talk to our technical services department for advice prior to application.

Surfaces that have fewer joints and are predominately large slab areas such as tar-macadam or concrete should provide the best finish. Bases that are made up of paving type products such as block paving, sets or flags ect. are NOT suitable for use as the base for a resin-based system.

The amount of cracks or lines below the surface of any resin applied to a paved surface would ultimately lead to cracks in the resin and failure of the system due to the extreme pressure loaded onto the system during day to day usage. Any freshly laid surface should be allowed to cure properly prior to the application of Gravelcoat. In the case of bitumen surfaces a minimum of 28 days should be given to allow it to weather and oxidise. For concrete at least 7 days should be given to allow it to cure properly. With any base it’s important that the moisture levels on the surface meets an acceptable level.

A primer may need to be used on on surfaces that may be permeable. Any edges should be masked off with a suitable tape, this will need to be removed before the resin is fully cured, as if left too late a clean straight edge would be difficult to achieve. Ensure there is sufficient fall on the area to allow drainage. For concrete surfaces a primer is recommended to ensure a good bond to the surface, this is generally a two pack fast curing epoxy primer with a scattering of C52 sand which will set in 90 mins or so.

Despite claims by some manufactures, wood decking, paving flags or block paving are not suitable for use with any resin surfacing system. Whilst decking could possibly be coated on an internal application, the poor stability of timber will ultimately lead to cracking in the resin. If a wooden base is to be used, only a proper exterior grade wooden deck surface should ever be considered.

With the exception of applications such as tree pits, resin-based surfacing cannot usually be laid on a granular sub-base, such as a layer of Type 1, gravel or sand, no matter how well compacted. Damp striking up through the base could affect the resin and if there is high moisture content in the base it can seep into the resin with adverse affects such as clouding of the resin.