Comfort, you say?
- Not too hot, not to cold – just right, always.
- Healthy indoor air quality.
- Calm, peaceful spaces.
- A place for well-being.
Hands up who wants a home with these qualities?!
Heading along to the Passive House Conference in Melbourne recently, organized by the Australian Passive House Association, I was expecting a lot of technical information over the two jam-packed days. There were 24 presentations, plus workshops and a tradeshow. However, the biggest message from the local and international experts was to remind us that Passive House is all about occupant comfort, and this is achieved with well-designed (& well-built) passive buildings envelopes. This might sound obvious, but so often with discussion of the Passive House standard, the focus shifts to discussions of energy-efficiency and also the mechanical-ventilation system (which is really only a small component).
For those not in the know, this international energy-efficient construction standard originated in Germany, and has five basic principles, which are all about preventing unwanted heat-transfer (via convection, conduction and radiation):
1 Well insulated building envelope
3 Great windows – double or triple-glazed with great frames and good seals
4 Eliminate Thermal Bridges – to prevent heat/cold transfer through the building frame
5 Controlled Ventilation – usually with a small mechanical heat-recovery ventilation system
At the conference, the big questions/concerns were all addressed specific to our locale:
Is the Passive House standard really relevant for our Australian Climate/s?
Absolutely. Depending on our location, as soon as we get below about 18 degrees or above 25 degrees the heating/cooling system usually goes on – that’s a lot of energy use. Approximately 40% of an Australian home’s carbon emissions comes from heating and cooling. Passive House buildings are thermally-comfortable all year round, and do not require heating/cooling – think of the running-cost savings, not too mention the environment. Many examples were shown of different scales and different climates, with the certification and data to prove performance. Orientation is still ‘king’ – you can’t ignore the sun when designing and appropriate shading is required to ensure overheating doesn’t occur.
Is it affordable?
There was a resounding yes! Some data of built examples suggested that houses could be at the $3000/m2 mark, or less – especially once local experience and products improve. Some said on average it might be 15% more upfront build cost – but if you look at the life of the building, the payback period was within a few short years with such low energy-use and minimal running costs. Architects already know the quality vs. quantity argument all to well – it’s worth remembering that if our oversized homes were say 15% smaller, this saving could go to making them better quality, more energy-efficient, and for the same price.
Is it achievable?
We may be a few years behind the rest of the world, but we can catch up! The emphasis was on ensuring that everyone in the team was on board with building to a high-performance standard – it must be a collaborative effort between the client, architect, consultants and contractors. It was also noted that this standard is not ‘rocket-science’ but it is ‘building science’, and that it is simple (in principle) but not easy to undertake. Bronwyn Barry (USA) noted that “it is like trying to sell space-ships to people used to buying billy-carts” – that in the last 100 years or so the way we build hasn’t really changed! A number of speakers reiterated that introducing the prospect of designing and building to Passive House standard is all about managing (and raising) client expectations.
What do Passive Houses look like?
There is the misconception that Passive Houses look like little German boxes with a few windows punched out, but of course as long as you meet the requirements of the standard in terms of the building envelope, you can still have a lot of design freedom. There were some gorgeous examples of certified Passive House Architecture as presented by Andrew Michler (USA) – and you can find them in the International Passive House Database.
It’s just for homes, right?
No! The name does do the standard a disservice, as it is applicable to commercial, cultural and multi-residential buildings too. A presentation by Elrond Burrell from ArchiType in the UK focused on their educational buildings – including what has been labeled THE greenest building in the world – The Enterprise Centre at University of East Anglia.
So, let’s get this straight.
You can have a truly healthy and comfortable home. It may cost the same to construct, yet can have up to 90% less ongoing running costs (!) You can still design beautiful bespoke architecture. Oh, and did we mention that this will save a huge amount of CO2 emissions; and help save the planet for our children?
I’m feeling pretty convinced. You?
A reminder that a 6 star energy-efficient home is actually ‘the worst building you can legally build’. Architects are high-performance individuals – I think we all have a responsibility to aim higher, and ensure our buildings are also high-performance.
Talina Edwards is director of Talina Edwards Architecture