When an overlay works
An overlay is only as good as the surface underneath. Tarmac or concrete that is level, stable and free from large cracks can usually take resin. Surfaces that are breaking up, sinking or full of tree roots need repairing or replacing first.
How an existing drive is checked
The installer looks for cracks, movement, low spots where water sits, and how the drive meets the house and pavement. Small cracks can be repaired, and expansion joints may need treating so they do not reflect through the resin.
Drainage with an overlay
Resin over solid tarmac or concrete is not permeable, because the base underneath stops water soaking away. Water must run to a drain, a soakaway or a planted area within your property. See our planning and drainage page.
Questions
Is an overlay cheaper than a full new driveway?
Usually, because there is less excavation and base work. It only makes sense if the existing surface is sound.