If you’ve read my post about deciding to build a house, you will know that we were keen on building an energy efficient home. Canberra has a cool temperate climate, so it gets very hot in Summer and pretty darn cold in Winter! Personally, I’m a Summer lover, so while I appreciate the four distinct seasons we get, I hate feeling cold.
With that in mind, we selected a builder who specialises in energy efficient homes. Luckily for us, he was in the process of becoming a certified ‘Passive House’ builder. If you are not familiar with this concept, check out this video, Passive House Explained in 90 Seconds.
We knew about some of the better-known passive design principles like placing large windows to the North and small windows to the West and incorporating appropriate shading, but we were intrigued to find out more about what the German’s have been doing since the 90’s. We pretty quickly decided that since we were already investing a lot into building a long-term home, it made sense to go the extra mile to minimise our energy bills and do a bit for the environment at the same time.
This has driven some of the design and material choices including:
- insulating underneath and the perimeter of the concrete slab
- increasing the exterior wall cavity (a teeny 20mm) to allow for more insulation
- selecting UPVC windows and doors
- not recessing anything into the exterior walls or roof cavities
- selecting external roller blinds
- installing a Heat Recovery Ventilation system
In short, this means our house will be super insulated, airtight and ventilated, so it will maintain a pretty consistent temperature year-round, and won’t need much heating in Winter or cooling in Summer. So no more draping damp face washers over my head to try and get to sleep in a stifling heat box or toting around a hot water bottle, wearing a blanket and drinking eleventy cups of of tea, in the frosty months!
Building to Passive House standards doesn’t have to cost much more than a standard build. We opted to have hydronic in-slab heating because I find convection heaters dry out the air too much and we wanted concrete floors (I had my heart set on walking around in socks!) but most people find a split system does the trick, so save money by not installing ducted gas heating and air-conditioning systems.
Here are a few pics post demolition and some of the passive house materials we have used so far…