Leading the market in house energy performance, this 9.1 star house was one of the first in Australia to achieve this rating. What does this mean in terms of energy efficiency? A 9 star house uses 80% less energy to heat and cool than a 6 star house (the current standard), and only 1/10 of the energy of average existing housing stock. This means that if you include LED's for your lighting and are careful with your appliance selection it is possible to have a house that uses very little power. If you then include a grid interactive photovoltaic system, as the clients in this house did, it is not too difficult to produce more power than you use. Indeed the first ever bill for the Penola house was $700 in credit!
The house also boasts a very comprehensive environmental specification list, including polished eco-concrete slab, bagged recycled reverse brick veneer walls to bring mass into the upper floor, and high performance double glazed timber windows. Rainwater harvesting with internal re-use and greywater collection with sub-surface distribution to the now drought-proof garden, complete the package.
And the roof shape? This came about for the following reason: The small site is narrow and runs east-west. The need for solar access and a viable backyard for food production, plus a flood overlay of 600mm, made it inevitable that the house would be double story and sited to the south of the block to help protect its solar access from future development by the northern neighbour. But a high performing passive solar home that blocks solar access for its southern neighbour is counterproductive in environmental terms. This problem was resolved by a curved roof, which maximises head height whilst minimising overshadowing by falling away to the south side. Round windows further play on the curve created.
This is an example where following sustainable principles can not only lead to good function and high performance, but also to imaginative responses and just a touch of whimsy.
Download the factsheet for the environmental features of the house.
See editorial article in Sanctuary Magazine Issue 18, entitled, "Leading Edge"
Our clients were also interviewed by Channel 10 in May 2012, when there was speculation that the Victorian Government would scrap the house energy rating requirement, under its war against "greentape". This 'initiative' was thankfully overturned within hours of the airing.
Also read Elizabeth's blog about Building a 9 star house.
2011 Australia BPN Sustainability Award for Best Single Dwelling
2012 Master Builder Association Excellence in Housing Award under Best Sustainable Energy Home
Photo credits: Chi Cheung and Positive Footprints