Medical centres, surgeries and hospitals may have to review their heating and ventilation strategies as the NHS attempts to dramatically cut its carbon footprint.
Under its Carbon Reduction Strategy, now launched for consultation, the NHS plans to reduce emissions 60% by 2050 in all areas including building energy use.
Proposals include forcing every NHS trust to have a carbon management strategy by 2009 and demanding organisations report annually on their progress.
Cal Bailey, marketing director at NG Bailey, which is providing mechanical and electrical services for two new hospitals in Liverpool, said: "Not much progress has been made in this direction by the NHS up to now. It is the right thing to do for all property owners and the NHS is no exception.
"Until now patient care and cost have been the primary drivers and sustainability has not been. Now legislation has put it on the radar."
He said hospitals posed challenges to sustainability strategies because of the higher temperatures in premises compared with other public buildings, plus the need to promote cleanliness and infection control.
The NHS is responsible for more than 18 million tonnes of carbon dioxide each year from heating and lighting, powering its equipment, procuring goods and services and transport for patients and staff.