A WATCHDOG has called on the next government to immediately commit to an aggressive energy efficiency strategy, saying millions of UK homes continue to “leak cash” every winter.

A new Which? report says the UK’s housing stock continues to be among Europe’s least energy-efficient because of poor insulation despite the efforts of successive governments.

The report, A Local Approach To Energy Efficiency, says Government figures from December show up to 5.4 million homes still do not have their cavity walls filled and up to 7.4 million still need their lofts fully lagged.

According to Age UK, the NHS spends £1.36 billion each year treating illnesses caused by and exacerbated by cold homes.

The report calls for a switch to a long-term approach partly funded by a levy on energy suppliers and paid into a central pot, with funds allocated by a central administrator to local authorities for them to lead the roll-out of energy saving measures from 2017.

It also wants an overhaul of the Green Deal, noting that only 399 plans have been taken out on average each month since it launched, and clear insulation targets and delivery plans extending over the next ten years.

And it has called for greater scrutiny and oversight of the money spent from consumers’ bills on energy efficiency, saying it is not practical to expect more public funding or levies on bills to fund such measures so existing resources must be delivered more cost effectively.

Which? executive director Richard Lloyd said: “With millions of homes still not insulated, energy efficiency is a collective failure of successive governments.”