What work/cost is involved with an Overlay compared to a Full Dig-Out.
We can provide you with estimates for a simple 1 day overlay and also for a 1 week full dig out with overlay. Fill in the form below with the size of your area.
An overlay of your existing surface offers a cost-effective way to enjoy the aesthetic appeal of a Resin Bound Stone surface. This option follows the current contours of your current surface, providing a visually pleasing result. However, it’s important to note that the whole system is not completely porous. While rainwater will still drain through the Resin Bound Stone, it will hit the existing mid-layer and run off similarly to the current setup.
This technique is suitable for laying over existing concrete or tarmac driveways, slabbed paths or patios. The 18mm depth of Resin Bound Stone should seamlessly meet the vertical walls or existing edging stones. We advise against using aluminum “L angle” beading to contain the ResinBound Stone at the edges, as it may pivot over time when stepped upon, potentially causing cracks.
For a successful overlay, the current surface must be solid, free from subsidence, cracks, or looseness. Small cracks and potholes can often be reinforced using Heli bar and extra Resin Bound Stone. To ensure longevity (at least 15 years), the sub-base is crucial, requiring a minimum of 150mm depth of properly compacted type 1 sub-base below the current mid-layer.
We do not recommend overlaying block paving or brick laid on sand, dust, or glass, as the blocks are not securely fixed and can move. In such cases, a one-day overlay is not possible. The blocks will need to be removed and recycled, followed by the addition of more sub-base the surface up-to level. Pedestrian surface options include 30mm depth recycled plastic reinforcement resin trays or a 5mm fibre mesh before laying the 18mm Resin Bound Stone Surface. For sloping driveways, we recommend using 65mm of porous tarmac over the reinforcement tray/mesh method.
Full dig out
If your current surface experiences subsidence or consists of grass or loose stones or a combination of different surfaces, a full dig-out will be necessary. This involves excavating and laying a solid foundation of sub-base MOT type 1 at a minimum depth of 150mm. Next all manholes and gullies will be replaced to meet the finished surface height.
For open edges (not against property or garden walls), a robust stone edging is essential. This includes thresholds between your drive and the pavement, where concrete path edging or block paving is set in dry mix concrete. Additional features like raised planters or retaining walls are also constructed at this stage.
For pedestrian surfaces, you can choose between recycled plastic reinforcement resin trays or a fiber mesh, followed by the use of aluminum “L angle” beading for defining contrasting blend colors for borders, paths, and patterns. In most vehicular access cases, a mid-layer of open course, porous tarmac at a depth of 65mm is laid before the final 18mm Resin Stone Layer.
While the costs associated with a full dig-out are higher, this method allows for alterations in heights and falls, ensures complete porosity (SuDS compliant), and guarantees the quality and durability of the final product for 15 years.