Surface dressing is a preventative treatment, to prolong the life of the roads. It is an essential part of Dorset Council's road maintenance strategy, alongside patching and resurfacing.
Why we use surface dressing
- helps prevent potholes forming by providing a waterproof seal
- improves skid resistance, with a thin layer of new stone chippings spread on the finished surface
- is very cost effective; roads can be kept in good condition for longer, so that resources can be directed to fully resurface the roads that need it most. Full road resurfacing costs 12 times more per mile
A newly dressed road may feel 'bumpy' as the grip will have been restored. The surface will also be noisier initially while the chippings 'bed down'.
About the treatment
Surface dressing can only be carried out when the road is dry. When it rains, the work has to stop - changing dates across the whole programme of work.
It is a quick process - rural sites take less than a day to complete and urban roads will take 1 to 2 hours, depending on the length of the road.
Bitumen binder (glue) is sprayed onto the road, stone chippings are spread onto this and then compacted down with a roller. A sweeper then travels along the road the following day to clear any immediate loose chippings.
Surface dressing in action
Closing the road
We have a team of 20 people, two purpose built chipping spreaders, one spray tanker, six lorries feeding chippings and two suction road sweepers. This is a lot of equipment to fit into the road, even without traffic!
Doing the work in the daytime
We cannot work overnight as surface dressing relies on the evaporation of water from the bitumen binder (glue) for it to set, and it needs traffic to travel on the new surface for it to 'bed down' and lock onto the old surface.
We also cannot work in wet weather - any amount of rain or surface water dilutes the bitumen and so doesn't hold the chippings in place - which is why our surface dressing programme runs from April through to September. In rural areas we will be working 8am to 4pm and in urban areas we will be working 9am to 4pm.
There may be loose chippings still on the road. It takes cars driving on the surface to help the stones bed into the bitumen.
This is why there will be 20mph limit after the work. Travelling at a reduced speed through the newly dressed area will prevent skidding on the loose chippings, it helps 'bed down' the material and it will save your paint work! We sweep the road the day after the work to get rid of excess stones.
How you can help it go smoothly
After surface dressing your road, we hope not to bother you again for another 10 years!
But there are a few things you can to do help us, and yourself:
- please move your car off the road before 9am
- please keep children and pets away – for safety and cleanliness
- please keep to the temporary speed limits and avoid heavy braking to allow the surface to stabilise and ‘bed down’
- check your shoes before entering your car or home
- remove stains promptly with a cleaner for removing bitumen/oil which can be purchased from any motoring store
Before work starts
- yellow advance warning signs will be put up on affected roads two days before the work is due to start – each week we will publish on our newsroom the roads being dressed the following week
- please ensure you either park your car off the road or, if you need it during the day, move it to a nearby road (but check this road isn’t also being treated)
- wet weather causes delay and will change our programme
On the day we will
- sweep the road to remove any loose material
- cover all drains and manholes covers
- dress the road surface
- reopen the road
- loose chippings will be swept up the day after the work
- uncover taped up drains and manhole covers
- white or yellow lines and disabled bays will be replaced within 14 days