Nearly two years since the retrofit - what's it like?

We've now lived through 2 winters in this house since the thermal improvements were completed. And as you might expect, the difference is massive.

Going from a 1950's house with no insulation whatsoever, to a refurbishment at around the Passive House refurb end of the scale represents a radical transformation in terms of comfort. We now experience a level of thermal comfort that we didn't even know existed!

During the first summer, the house warmed up nicely, so that by the beginning of our second winter after the refurb, the bricks were fully warmed. This meant that we needed no heating at all during October to keep the house at a steady 21 degrees C.

Gas use in the second winter was therefore even lower than in the first winter. We used 4440 kWh of gas in the year to July 2014, of which at least 1800 kWh we estimate to be for hot water use and at most 2640 kWh for heating. And that's to keep the living areas at a very comfortable 20-21 degrees C through the winter (and the bedrooms slightly cooler, as we prefer it).

We used the EnerPHit standard as a guide. Houses that achieve this standard should use no more than 25 kWh / m2 / yr for heating. In the last 12 months, we used 21 kWh  / m2 / yr - so the house is performing as it was designed to do.