Comparing different road surface treatment methods
As the uppermost layer of the road, road surfaces serve as the contact point between the vehicles and the underlying structure, bearing the brunt of traffic and weather. Just as a functional road surface ensures safety and smooth travel, a damaged one means danger and inconvenience.
So, when the road surface needs treatment to keep it performing at its best, which solution should you choose? Here’s a look at the main options.
Surface dressing
A cost-effective method, surface dressing involves spraying a layer of liquid bitumen to create a protective, water-resistant layer. This is particularly effective at preventing potholes, improving skid-resistance, and sealing the road to prevent water-damage.
Advantages
Surface dressing is ideal as a preventative measure for minor defects and to restore the road’s texture. The treatment typically lasts up to 10 years and is most effective when applied in the warmer months, from April to September (surface dressing cannot be carried out in wet or overly hot or cold conditions).
Disadvantages
Surface dressing doesn’t address structural issues or heavily damaged roads
Slurry Seal
Slurry seal is a low-cost, preventative treatment whereby a mixture of bitumen emulsion, aggregate, and water is spread and brushed to fill minor voids and level depressions in the road.
Advantages
Slurry seal is a low-cost, preventative treatment that can protect a road surface or footway from moisture damage.
Disadvantages
Slurry seals are typically only used on minor roads because it is not as durable as other treatments. After application, the slurry typically remains wet for several hours, necessitating temporary closures. In addition, weather conditions must be dry and temperate for successful application.
Crack Sealing
Crack sealing is a process in which shallow rebates are milled into cracks, cleaned, and filled with a hot rubberised bitumen mix containing aggregates, recycled rubber, and fibres for reinforcement. Fine granite chippings are then applied to create a non-slip finish.
Advantages
A cost-effective solution to repair small cracks
Disadvantages
A temporary solution rather than a total fix, crack seals cool within an hour, but roads may need to close briefly to prevent damage from molten material.
Retexturing
Retexturing involves firing steel shot or high-pressure water (up to 1,000 bar) at the road’s surface to expose the underlying aggregate and restore the friction levels of the surface.
Advantages
Retexturing is an efficient and environmentally friendly way to improve grip and extend the road’s life. Its application window in colder conditions and the use of advanced equipment also ensure minimal impact on road users or local communities.
Disadvantages
The process can only repair the texture of the road and not any deeper structural issues.
High Friction Surface Treatment (HFST)
HFST is a process whereby specialist aggregates are combined with resin and laid onto the road to improve the friction of the road’s surface.
Advantages
HFST is extremely skid-resistant and has been proven to reduce crashes at all intersections by up to 20%. It is also highly durable, typically lasting up to 10 years, which is considerably longer than slurry seals or other surface overlays.
Disadvantages
HFST cannot repair any issues with the road’s substrate and often surface preparation methods such as texture blasting are required prior to its application.
To explore the optimal time, location and methods for applying HFST take a look at when, where and how to use high friction surface treatments effectively.
Resurfacing
A more comprehensive treatment, resurfacing, involves the removal and replacement of the road’s top layer. This method is best suited for roads that have deteriorated significantly and is more expensive and disruptive than surface dressing.
Advantages
Resurfacing can greatly improve a road’s durability and performance, extending the road’s lifespan by around 15-years.
Disadvantages
It is typically reserved for roads with more serious damage, as it involves extensive preparation, a longer application process and a significantly higher cost.
To find out more about how you can extend the life of road surfaces speak to one of our experts.