Sustainable House - Retrofit House
By Tony Wolfe
For a long time I have been passionate about energy efficiency so when I purchased this property which was a “renovator’s delight”, it seemed logical to achieve the highest possible standard that I could economically obtain.
I have worked in the power generation industry all of my life and I could foresee the rapid increase in energy prices coming so the intention was to produce a house that left minimal footprint and relied little on services. This house renovation was a part time interest that took approximately 5 years to complete. As I carried out a lot of the grunt work myself under the direction of my builder, it is very satisfying to sit back and enjoy the benefits.
I am an Electrician specialising in lighting so great detail went into careful selection and semi-automation of the electrics throughout the house. I am quite proud of the fact that over a 12 month period, the usage costs of electricity, gas and water has been less than $400 in total. Incorporated in the design is a 4.5kW PV system, rainwater storage tanks, solar storage hot water and low maintenance gardens.
The inclusion of electrically operated clerestory windows promotes cross flow circulation in hotter weather drawing air across a pond located on the south side of the building. The carport is fitted with a power supply to allow charging of my plug-in hybrid vehicle. Synthetic lawns (including the nature strip) ensure there is never a need for mowing.
Cost estimate of sustainable home/features
Total cost of home when constructed
Estimate of annual savings
BAL – Low: There is insufficient risk to warrant specific construction requirements.Roofing materialsMetal (Colorbond)
Wall materials (external and internal)
Insulated panels or blocks
Window and door types
Awning / Bi Fold / Clerestory windows / Double glazing
Recycled and reused
Insulation - Under roof
Type: Air Cell Rating: R2.0Insulation - Ceiling Type: Bulk - glass wool Rating: R5.0Insulation - External walls Type: Insulated panel system Rating: R6.0Insulation - Internal walls Type: Bulk - glass wool Rating: R2.5
Cross flow ventilation Indoor plants for air filtration Natural light and ventilation No carpets
Energy star rating
First Rate - Energy star rating 8
Solar PV grid connect 4.5kW
Solar hot water (evacuated tube)
Passive heating cooling
Cross ventilation Shading
Split system airconditioner
Efficient lighting Efficient appliances Smart home features
Mitsubishi Outlander Plug-In Hybrid Electric Vehicle (PHEV)
Water harvesting and saving
Above ground rainwater storage Colorbond rainwater tank Low flow shower heads Low flow taps
Garden/OutdoorsNative plants Water wise plants Synthetic grass