Improving my house’s heating and cooling and energy efficiency is an ongoing project.
- 2008 Solar hot water
- 2012 Ceiling fans and roof insulation
- 2015 External blinds
- 2017 Air-conditioning (a backwards step for energy efficiency, but a giant leap for comfort on very hot days)
This week it was wall insulation.
Obviously this is best fitted when the house is built, but in a house built circa 1930, the only way is to retrofit it.
They do this by drilling small holes in the walls all the way around the house, then spraying in filler stuff into the wall cavity.
They’ve filled the holes, but they’ll need sanding and painting, which leaves me somewhat regretting I didn’t do this before I got the house painted in 2015. Not to worry, but for now the house looks like it has measles.
Last year’s winter gas bill (covering 15th June to 15th August) was a whopper, at $489 ($7.87 / 354 MJ of gas per day) – similar to 2016. (In 2017 we were away on holiday for some of winter.)
I’m hoping that by getting the new insulation in time for winter, the gas bill for winter this year can be reduced quite a bit – hopefully daytime warmth can be better retained into the evening and overnight.
It might be a while before the investment (not insubstantial) pays off, but already there’s a noticeable difference, which is good.
Future options around the house include:
- double-glazing on the windows
- under-floor insulation
- PV panels for the roof
- replacing gas cooking with electric
- replacing gas central heating with more reverse cycle units
- and one I learnt about recently which seems like an easy no-brainer: a balloon in the fireplace.