House with a Sense of the Past
Old terrace houses are not usually the most efficient beasts. They are notoriously difficult to heat in winter. In summer their thick brick walls will stay cool for a little while, but once they heat up they could be considered a decent oven. So when you have a terrace are you automatically excluded from the quest for sustainability?
Nettleton Architects have demonstrated that even with prescriptive heritage requirements, a terrace house can be transformed into an efficient, comfortable and sustainable home.
Timber Screens for a Warming Climate
Nettleton Architects started with the assumption that due to a warming climate Sydney will experience hotter summers and more extreme weather. They introduced external timber screens to many of the windows. These screens have the double benefit of keeping the house cool in summer, and adding an extra layer of insulation during the winter.
Louvre windows are another feature of the new sustainable renovation. The louvres promote cross ventilation to cool the house when necessary. This flexibility is an important part of keeping the occupants comfortable. There's a lot of science around thermal comfort, but basically, if occupants have the ability to control their environment by opening louvres and closing screens they will feel more comfortable even at more extreme temperatures.
This new flexibility is good news for the occupants as Sydney is set to experience more extreme weather.
As well as physical screens, lush green plants have been planted around the house to act as natural screens. Plants can act as great natural coolers. By opening windows and drawing air into the house past the plants' cooler micro climate is a good strategy to cool the home in summer. Plus, greenery has a great psychological effect -- everyone likes looking onto a bit of greenery.
More Efficient in Winter Too
Hydronic radiant heating was installed to make the home more comfortable and efficient in winter too. Again, the thermal comfort of the occupants has taken precedents. Radiant heat is the most comfortable way to heat a space -- compared to ducted heating, for example, it provides a gentle, consistent heat.
Hydronic heating is also very efficient. While this system uses natural gas to heat water in the boiler, solar boosted systems are a great sustainable option -- even in retrofits. In this case, the roof didn't receive enough sunlight to make a solar boosted system worthwhile.
The house has been thoroughly insulated to keep all that warmth where it belongs.
Open Plan Living
A common complaint about terrace houses is the 'boarding house effect' -- pokey little rooms that are disconnected, dark and completely inappropriate for modern living. Nettleton Architects conquered the boarding house by opening up the ground floor into an integrated open plan.
Ceiling fans are fitted throughout. They are a low-cost way to keep the house cool and promote cross-ventilation.
On the upstairs balcony, the timber screen keeps the heat of the sun at bay and protects the occupants' privacy. A peep hole ensures the screened area doesn't feel claustrophobic and provides a nice view over the neighboring streetscape.
Several skylights get light into notoriously dark corners of the terrace. This round skylight creates beautiful curved rays of light.
Sustainability for the Future
Darlinghurst Terrace is a great example of simple techniques that can dramatically improve the sustainability of our numerous, inefficient old houses. The basic principles of shading, ventilation and maximizing thermal comfort have been incorporated at low cost, but maximum benefit.
It's much more sustainable to improve the efficiency of buildings we already have rather than start from scratch. Hopefully more people choose to work with an architect to improve what they've already got. The outcome is a home that's cheaper to run, more environmentally friendly and more comfortable.