Remember last August? I do. The couple of weeks that sent my sinuses into overdrive. Pretty sure I was not alone.
The hazard reduction burns in bush areas created an environment where one smelled like smoked salmon from a two-minute walk outside. The weather had been over 24°C for mid-August. You could have been forgiven for thinking it was summer for a few days. There was one day in particular where the gods whipped up a wind storm that saw trees overturned, roofs fly off homes and pollen wave by, disrupting the breathing (again!).
Replying to an email from a Victorian friend, I signed off, “I want to live in a passive house!” Less than 30 minutes later I learned it was 8°C and raining down south. He replied, “I would like to live in a passive house too!”
I want to live in a house that is comfortable, that doesn’t leak air, both in and out. The holey mish-mash of a Californian bungalow that I call home is partly renovated. There are stories about architects and unfinished homes…
In a passive house in Sydney I would not have to heat or cool pretty much year-round. Give or take the 5-7 days of minor heating that may be needed, or to don an extra jumper and thick socks, or use the hair dryer to feel comfortable. Or the 5-7 days in summer that may be so hot the ceiling fans don’t manage to keep the family cool. A small wattage split AC unit may not even be worth the investment. May just have to go to the beach, or the mall.
In a passive house, I would not have to worry about the “poor air quality” that has occurred more times than I care to remember in the past few years, causing havoc to my perennial sinusitis. The energy recovery ventilation (ERV) unit would filter the incoming air, replacing 30 per cent of the inside air every hour. Easy to maintain; checking and replacing the filter as recommended is just good building maintenance. Checking it a little more often as the surrounding area undergoes its urban renewal, sharing its fine particulates of dust, would be wise. This has additional benefits of removing toxins produced by being human and using a building (I cannot give up breathing). Keeps CO2, VOCs and mould at bay, as an added bonus there would be no more smelly socks and teenage odours from closed doors to deal with.
Knowing the insulation in the building envelope (yes the walls, windows, roof and floor) is keeping my home’s interior at a constant temperature range year-round would bring relief. So too would keeping the quarter energy bills to a minimum, a real minimum – there’s potential for 90 per cent reduction annually.
I know the windows and doors can be opened, so the indoor–outdoor lifestyle can be maintained. It would be worth the investment in thermally broken well-sealed double-glazed windows and doors. The plane spotting could be done without the noise, or hearing that traffic. The neighbours wouldn’t be able to hear the saxophone, oboe, piano or electric and acoustic guitars being played, and comment on the “player’s” improvement, or otherwise.
The Passive House standard requires an airtight building envelope. That doesn’t mean you cannot breathe in it. Quite the opposite, in fact, if you “build tight – ventilate right”, as the saying goes. Did I mention I can still open the windows?
The standard also requires that the building be as thermally bridge free as possible. This is just a fancy way of saying the building’s construction system isn’t letting thermal energy pass through it. This can be easily achieved with good planning, design and construction. There are so many solutions to ensure that unnecessary thermal bridges are designed out.
Now, I need to get back to the drawing board, for my family passive house design version seven, or was that 17?
Kylie Mills is a director of BluKube Architecture and the Australian Passive House Association, and a member of the Australian Institute of Architects.