Kerbs need to be at least 60mm high to work for blind and partially sighted people, says Guide Dogs

Research undertaken for Guide Dogs by University College London (UCL) has demonstrated that the minimum height for a kerb to be reliably detectable by blind and partially sighted people is 60mm or greater.

No participant in the research failed to detect the 120mm, 80mm, or 60mm height kerb in any trials, from any angle tested, or for either of the edge profiles. In addition, kerb heights of 60mm and above induced the greatest confidence in what they were and what they signified.

Sue Sharp, Guide Dogs’ Head of Policy and Campaigns, commented:

“Designers have been reluctant to introduce traditional kerbs as part of shared space designs because they consider them to provide too distinct a separation between the road and pavement and so would dissuade drivers from modifying their behaviour. As a consequence kerbs typically of 30-50 mm have been provided in many schemes. Guide Dogs was concerned that such kerbs were not distinct enough.

“This research supports Guide Dogs’ position, establishing that the low kerb heights being introduced across the country as part of the shared space schemes are not an effective delineator for blind and partially sighted people.

“We hope that the design community will take heed of these findings in new schemes and introduce kerbs which will work for blind and partially sighted people, alongside dropped kerbs and tactile paving.”

As part of its “Say NO to Shared Streets” campaign, Guide Dogs has been calling for kerbs to be retained as a delineator between pedestrian and trafficked areas: there are no proven alternatives. The findings of this research should inform the designs of those who will only countenance a lower kerb height in their schemes.

Effective Kerb Heights for Blind and Partially Sighted People (word) 588kb

Effective Kerb Heights for Blind and Partially Sighted People (pdf) 699kb