First, we looked at official dwelling approval data. We then examined certificates issued under the Nationwide House Energy Rating Scheme or NatHERS. This gave us the thermal performance star-ratings of the new homes, their energy efficiency for heating and cooling and their conditioned floor areas – that is, floor areas typically heated and cooled, excluding spaces such as laundries and garages.
From our washing machines to cars, we know a lot about the energy efficiency of the products we buy, so why do we have so little information about our biggest investment – the family home?