The lower threshold for air-conditioning inspections came into effect on 4 January, 2011.

"With the recent changes in the threshold a lot more buildings now require an inspection. CIBSE believes it is the ideal time to introduce the mandatory lodgement of air-conditioning inspections to help monitor compliance," said Hywel Davies, CIBSE technical director. "It will enable us to build up a national picture of air conditioning."

The government has announced it will take forward proposals to make it mandatory to lodge air-conditioning reports following an industry-wide consultation, but the timescales are still to be determined.

"Implementing a mandatory lodgement requirement for air conditioning inspections will bring an increased focus on these inspections," said Hywel Davies, CIBSE's technical director. "Air conditioning inspections have the lowest compliance rates, we think below 5%. The industry needs to increase compliance to achieve carbon emissions reductions targets and increase the energy efficiency of buildings."

The purpose of air conditioning inspections is to provide owners and operators with information on the performance of their air conditioning so that they can improve them and cut costs if they are using too much energy. The mandatory lodgement will provide a central register enabling much better information on air conditioning installations.

It will bring air conditioning inspections into line with energy performance certificates and display energy certificates which are already collated and stored in a central database, to help ensure a consistent approach to measuring energy efficiency in buildings.