The building of the government body tasked with cutting the carbon emissions of public buildings has been handed an 'F' rating by energy efficiency assessors.Eland House, where the Communities and Local Government department is based was given the second-worst rating possible under the Display Energy Certificates initiative.The scheme, which will require wholly or partly public buildings larger than 1,000 metres squared to prominently display their energy efficiency, is set to start in October and the Eland House building was assessed in anticipation of the deadline.Officials from the department told the Guardian that poor heating and ventilation systems, as well as higher occupancy than expected, was responsible for the poor energy efficiency rating.A spokesman for the CLG said: "Our rating for Eland House tells us we must clearly do better to make a difference to our energy performance. We are now acting on recommendation from our advisory report to help us improve future ratings."