More than five years ago, through the Sustainable and Secure Buildings Act, we gained the legal powers to improve the sustainability of existing buildings

Thus were born “consequential improvements” – a requirement under Part L to upgrade an existing home when carrying out a refurbishment.

The idea received huge support. The measures are all either low cost, subsidised, or simply bring forward the inevitable by a couple of years. Nobody could believe it when the government did a last-minute u-turn on this in the previous Part L.

Fast-forward to 2009 and the Heat and Energy Saving Strategy consultation, which in February set out our new national target: loft and cavity wall insulation for every home by 2015, and all buildings to be zero carbon by 2050.

The tales about the scale of this challenge were frightening: “We must spend the same as the entire cost of the Olympics every year until 2050”. Hence, consequential improvements went back on the menu.

So to abandon them yet again, for all but the biggest existing homes, is just staggering. It’s rather like deciding to ditch your oxygen before you even leave base camp on the way up Mount Everest.