In short
Surface dress a road that is structurally sound but going grey, porous or slippery; resurface one that has cracked, rutted or potholed through to the base. Dressing seals and grips, it does not add strength. The test is simple: if the faults are in the surface, dress it; if the road moves under a vehicle or the holes go through to stone, it needs resurfacing.
This is a job for our Road Surfacing service.
What each treatment actually does
Surface dressing is a spray of bitumen with stone chippings rolled in. The Institute of Asphalt Technology describes its job as sealing the surface, stopping water getting in and helping prevent potholes forming in the first place, while restoring skid resistance. It uses up to 75 per cent less bitumen and up to 80 per cent less aggregate per square metre than a thin asphalt surface course, which is why it costs a fraction of resurfacing.
Resurfacing means planing off or overlaying the old surface with new hot laid tarmac or asphalt, and where the base has failed, digging out and rebuilding the sub base first. It restores the strength of the road as well as the surface.
How we decide on a site visit
| What we see | What it means | What we recommend |
|---|---|---|
| Surface gone grey, stone showing, polished and slippery in the wet | Bitumen has aged; structure fine | Surface dressing |
| Fine crazing, no movement, no potholes | Surface drying out; water not yet in the base | Surface dressing, soon, before it gets worse |
| Isolated potholes in an otherwise sound road | Local failures | Patch the holes, then dress the whole road |
| Ruts, map cracking, edges breaking away, road flexes under a lorry | Base failing | Resurface, with dig out where the base is soft |
| Standing water, no falls, verges higher than the road | Drainage failure | Fix drainage first, whichever surface follows |
The mistake to avoid
Dressing a road that has already failed. The stone and bitumen will sit on top of a base that is still moving, and the cracks come back through within a couple of winters. Road Note 39, the industry design guide the RSTA publishes, is clear that dressing is a preventative treatment: it works on all types of road when the road underneath is sound. We will not dress a road that needs rebuilding, because it wastes your money and our name.
The opposite mistake is nearly as common. Estate roads around Petworth, Midhurst and Sherborne get resurfaced at several times the cost when a dressing would have sealed them for years. West Sussex County Council puts the extra life from a surface treatment at up to ten years, depending on traffic and condition.
Timing and the budget
Dressing has to be done in warm dry weather, so it is a late spring to early autumn job, and it is usually done in a day with slow traffic allowed the same afternoon. Resurfacing can be done through more of the year and takes longer, with the road closed section by section. For a long private road, the sensible plan is often both: rebuild the sections that have gone, and dress the rest so it does not follow them.