Public sector social housing are, on average, more energy efficient than those in the private sector, an energy expert has warned.

Some private sector properties are in a state of urgent disrepair, while government initiatives have led to local authorities paying more attention to ensuring energy standards are met. 

The private rented sector was also highlighted as the worst offender for energy efficiency by a study carried out by the Energy Saving Trust (EST) last month.

Marc Blomfield is managing director of The National EPC Company, which carries out Energy Performance Certificates (EPCs) across all housing sectors. “The authorities are prepared to invest in improving standards and will benefit from energy cost savings in the future," he said.

“Large old properties that have seen little investment over the years are likely to have old heating systems, poor insulation and inefficient boilers.

“Landlords in the private sector need to make sure they tackle these unsatisfactory house conditions and get them up to scratch. There will be little excuse not to when the Green Deal scheme launches in 2012.

“People investing in new properties must not fall into the trap of believing that everything new is energy efficient. This is just not true. The reality is that 10% of new properties fail the energy efficiency test too.”

A fifth of UK homes are rated as band F or G through the EPC - the least energy efficient bands.