Drivers are against the idea of a blanket 20mph speed limit on urban roads but are open to their targeted use, according to research published today by road safety charity the Institute of Advanced Motorists (IAM).

Half of drivers from the UK are against a blanket 20mph speed limit with less than a third willing to embrace the idea and a fifth undecided. Men are more likely to be against the idea than women.

Among young drivers 55% were against 20mph zones as a speed limit for towns while 34% of older drivers were in favour.

Drivers are very supportive of lower speed limits outside schools, with 94% of people surveyed agreeing that this would be a good idea. Only 8% opted for 20mph limits near cycle lanes.

More than three-quarters of drivers believe that 20mph speed limits help to increase safety for pedestrians, but only a fifth saw it as a positive advantage for cyclists. Pollution and noise were not seen as important benefits.

Using 20mph speed limit signs only to enforce lower limits was twice as popular as physical traffic-calming measures and three times more popular than using speed cameras.

Only a fifth of drivers think enforcing 20mph limits should be a police priority, while 68% would like to see a specially-tailored re-education course for drivers caught doing up to 30mph in a 20mph zone.

IAM chief executive Simon Best said: “Drivers are not as negative about 20mph speed limits as many commentators would have us believe. Those responding to our survey found it quite easy to stick to 20 and there is large-scale support for 20mph outside schools.

“However, most drivers don’t want 30mph zones to be replaced with 20mph in towns. Many drivers still need to be convinced it would be a benefit. Re-education is also much more popular than prosecution.

“Good design and widespread consultation is the key to the successful use of 20mph zones as a road safety tool because limits that match the road environment enforce themselves.”