Funding for new schools should be withheld if design proposals are not up to scratch, government design watchdog CABE recommended this week.

The warning was contained in a CABE report into the £45bn Building Schools for the Future programme. This said half of all schools constructed in the past five years were badly designed and built.

It recommended that all design proposals from the private sector should be submitted to a design review panel, led by the Department for Education and Skills. If the panel considers a submission unacceptable, funding should be withheld until revisions are made.

The report added that nearly all schools failed to tackle basic environmental issues, such as providing natural daylight and ventilation.

It said that any procurement route could produce good design, but all of the poorest schools except one used PFI, while only three of the best 10 schools did.

All the good and excellent schemes, which make up 19% of the total, were completed in 2005.

The watchdog also called for a fundamental review of school design briefs as a matter of urgency. It said that briefs had hardly changed in the past 20 years.