The character of St Albans would be dramatically altered should projected housing need figures be adopted, a district councillor has warned.

An independent assessment of future housing requirements has suggested the district pave the way for an extra 11,724 homes to be built over the next 20 years.

The appraisal was commissioned by St Albans district council to help guide its Strategic Local Plan, the planning blueprint which maps out future development.

But planning spokesman for the Lib Dems, Cllr Chris Brazier, said he was surprised at the figure, and warned that should it be entrenched in the local plan, “we would be building on the Green Belt”.

Portfolio holder for planning Cllr Julian Daly told the committee that a “crystal ball” was needed to project the number of people likely to move to St Albans by 2031.

Questioning figures in the assessment, he said some seemed unfairly “inflated” and risked placing more pressure on the council to meet projected housing need than was necessary.

After the meeting Cllr Simon Grover, Green leader, urged the council to focus on what was practical to build.

He too warned about the impact of future housing, adding that a lack of space for residents’ cars was also a problem.

Cllr Martin Leach, Labour leader, said: “The report is saying that in terms of affordability, there is an acute and worsening problem, which doesn’t come as a surprise.”

He said the assessment was an important document which provided evidence to help the council prepare the final version of its planning blueprint.