What does a red road surface mean?

Red asphalt generally means the area is reserved for bicycle or pedestrian use. Still, it can be used to delineate zones, prevent drivers from crossing into restricted areas, or highlight other risks.

Coloured tarmac is made and laid the same way as a conventional black or grey road surfacing system but features a pigment to achieve the desired effect.

Some common places you will see red roadway surfacing in the UK include cycle lanes, or lanes at traffic lights marked out for cyclists, ensuring they have a safe place to stop and resume their journey without queuing alongside vehicles.

Other areas with red road surfacing include intersections, cycle tracks, car-sharing lanes, and bus and taxi-only routes, and to bring extra awareness around accident black spots.

Using Coloured Roadway Surfacing to Enhance Safety

Most road markings, lines and coloured tarmacs are there to help drivers understand the correct way to navigate the road, particularly complex junctions, large roundabouts, or where smaller roads join a bypass or motorway.

Demarcations are useful because they stand out, make painted markings more visible, and contrast with the main roadway to ensure drivers and other road users are forewarned of upcoming hazards.

UK cities, carriageways and other routes often use red coloured road surfacing to indicate lanes for bikes or buses or to help reduce congestion, queues, and bottlenecks where drivers routinely misunderstand the signage or other instructions. 

Even the presence of a red road surface has been shown to reduce average traffic speeds, used on trunk roads to test driver responses and evaluate the safety case for coloured tarmac.

There has yet to be any official status or use for red (or other coloured) road surfaces, so while there are several popular uses, they do not always mean the same thing. Rather, highway authorities, landowners and commercial site planners can select their preferred tarmac finishes as appropriate.

Examples include green road surfacing to indicate car-sharing lanes or routes reserved for electric or hybrid vehicles, red lanes for no-access routes, and black for other roadways.

Developing a Durable Red Tarmac Road Surface

The best way to lay a red road surface is to work with an experienced highways contractor who can mix the pigment with the tarmac and bitumen. Adding colours to road surfacing retrospectively is inadvisable since paints and other materials applied over a pre-existing roadway will rapidly deteriorate or fade with exposure to UV rays.

Coloured tarmac has pigment embedded in the mixture, and a sealant or treatment will bind the components together for durability.

Additional additives can provide enhanced safety and be beneficial where the red roadway is there to raise awareness of hazards or frequent accident sites. Sand improves skid resistance, for example, and is increasingly used in cycle lanes or to reduce the risk of motorbike collisions.

The Diverse Applications for Coloured Road Surfacing

Red signifies a warning or risk and tends to be used in the same way as traffic signs, where a red light instructs a vehicle to stop, a red cross over a blue background represents a red route where stopping is forbidden, or a red triangle brings attention to a hazard such as an uneven road, double bend, or crossroad.

Highway planners use red tarmac to:

• Discourage vehicles from using a section of the road
• Calm traffic where collisions or high speeds are common
• Instruct drivers to follow a designated route
• Delineate restricted lanes, such as those for bicycles or car-sharing

Green road surfacing has the opposite impact and is associated with environmental awareness, so it can indicate a low-emissions zone, a lane reserved for electric vehicles, or a bicycle lane.

Pigmented tarmac is also widely used outside the public highways network, around residential estates, parking areas, industrial zones, and facilities such as airports, train stations, bus stations and ferry terminals.

Drivers can easily follow a colour-coded route, find the appropriate parking area, or avoid entering higher-risk spaces such as loading bays, container storage areas or zones restricted to official personnel.

The best practice is to support any coloured roadway system with signage and warning or advisory signs as used in The Highway Code, to ensure every driver, cyclist or passenger will understand the instruction or notice and take the desired action. 

However, in travel terminals, red road surfaces can be particularly effective, where visitors and commercial drivers arriving in the UK from overseas may not necessarily know the meaning of every road sign and could potentially make a serious error. In contrast, green and red are universal indicators of risk and safety.