Housebuilders have responded to criticism claiming that tens of thousands of new estates are poorly designed and dominated by cars.

They have placed the blame at the door of highways engineers.

The Commission for Architecture and the Built Environment this week accused four out of five new estates of being 鈥渕ediocre鈥 in design.

But housebuilders say well-designed projects approved by planners are often rejected by highways authorities who insist on conservative road layouts. John Oldham, director at housebuilder Countryside Special Projects said: 鈥淚n the end, we have to do what is acceptable to the highways authority, even when we know we can do better.鈥

Chief executive of the Housing Corporation Jon Rouse admitted highways engineers were bound by planning guidance 鈥20 years out of date鈥. The Department of Transport is considering revising the guidance.

John Smart, deputy chief executive of the Institution of Highways and Transportation, admitted some of the criticism was appropriate but said road safety was also an issue.

For example, in making the point that design should centre around pedestrians and not cars CABE had criticised the use of roundabouts and excessive parking provision on housing estates. But Smart said the roundabouts were very effective at reducing car speeds.