The late issue of final guidance on energy performance certificates and a shortage of trained assessors could put the government’s April deadline in jeopardy.

From 6 April buildings with a floor area greater than 10,000m2 will need EPCs when they are built, sold or let. Industry figures said the final guidance on the rules, issued late last month, had not left enough to time to prepare.

Jenny MacDonnell, research and policy officer at the British Council for Offices, said the concerns had been raised with the communities department. “The content of the training courses has not been finalised and we’re worried that there will be a lack of trained staff to issue certificates in April,” she said.

Hammerson said it had been forced to prepare early by working with engineers despite a lack of finalised criteria. It said: “Ideally we would have quite a lot more time for this.”

CIBSE aims to train 100 assessors by next month and 1,000 by July. The RICS launched its scheme on Monday and said it would take 10 weeks to qualify. BRE said its courses also started this week.