My Place: Built to last
Passive housing is in the news - it aims for huge energy savings, but brings increased building costs. Caroline Allen visits one home built with energy efficiency in mind and finds the savings are well worth the investment. Photographs by James Fennell
Last month, Dun Laoghaire-Rathdown County Council voted to include passive housing specification in the draft county development plan. It means that if adopted all new homes will have to meet higher building standards, but will have much lower energy costs.
Critics of passive housing say that meeting these higher standards - which typically include very high insulation, triple glazing, and energy-efficient measures such as heat pumps - will push up building costs even further in a market where developers are finding it hard to recoup costs. On an aesthetic level, they argue that design priorities in passive houses often come second to engineer-led solutions.
But Danish architect Kim Dreyer believes the opposite. He designed his house in the Wicklow hills 10 years ago to passive-house principles. The result shows that good design and sustainability can go hand-in-hand. "For me, the important thing is that design and architecture come first and sustainability is just one of the tools we use," says Dreyer, who acted as architect and contractor, employing individual tradespeople for the build that took 12 months. His experience provides plenty of insights for those keen to build a design-led sustainable home.
1 Express yourself
Dreyer, who is from Copenhagen, used the opportunity to pay homage to his Scandinavian heritage. "There are certain Scandinavian traits - part of the building is off-white cedar cladding which you wouldn't see very often in Ireland. The house has its roots in both Scandinavian and New England styles of architecture."
2 Location, location
"The house is also rooted in where it's situated - a rural location in the Wicklow hills. To me, that was important and it is a starting point in all my designs to reflect the location and unique character of the setting. I wouldn't want an urban-referenced design in the Wicklow hills' landscape. The building needs to reflect where it's set."
3 Get personal
"When it comes to hiring tradespeople, personal recommendations are critical, preferably from people with construction experience. With materials, research the source, the actual documented performance and use certified products only," says Dreyer. "The basic principles of passive house design involve very high levels of insulation and careful detailing to avoid heat loss in all areas." He installed underfloor heating and a ground-source heat-pump. "I chose not to install a heat recovery ventilation system at the time as it was a very new technology, but now I incorporate it in most of the houses I design."
4 On the money
Dreyer estimates that there was between five and 10pc additional cost in designing his home according to passive house principles, but says he has recouped that through savings on utility bills. "Luckily over the past 10 years, a lot of low-energy heating methods have become more common and affordable. There would be added costs if you compare the cheapest oil-fired boiler to a heat pump, but in the long run there are lower running costs. I look at the energy costs in relation to the size of the house, which is just under 4,000 sq ft, not just the heating costs. We use a lot of electronics so the actual energy cost in terms of heating and hot water is only part of the story. Things like LEDs also help reduce bills. Our heating and hot water certainly costs less than €100 a month."
5 Material world
"To me, one aspect of sustainability focuses on low-energy and CO2 emissions, but it's also about the materials we use inside the house and making sure that there is a healthy indoor climate. We went for solid oak floors and sheep wool insulation. The beams in the main living room are green-oak wind-felled timber, and all the paint used was low VOC (volatile organic compounds)," Dreyer says. Reclaimed slates were also used at the main part of the house. Natural materials such as limestone flooring and dark brown marble worktops in the kitchen add to the sense of understated comfort.
6 Show stair flair
Think beyond the functional with staircases. Although Dreyer designed the house in such a way that the front and entrance hall are low key and that the house reveals itself slowly, he made a statement with the stairs which are a combination of white plastered surfaces and white oiled oak. "I always try to make the staircase an interesting sculptural element. Our house is set on six different levels and this staircase is like an open sculpture, connecting all the different levels."
7 Go off-piste
"One of the ingredients in creating a good home is low energy and sustainable design. However, everyone has to design for their own taste and it was my choice to have an open fire because I like to have one going every evening. It's not as energy-efficient as it could be, but I have no regrets. You need to have the right balance between principles and personal taste," he contends. "I didn't install a stove because when you have an incredibly well-insulated building, you don't need the stove as a heat source. Heat pumps work best and most efficiently, providing a low level of heat on an ongoing basis."
8 Less is more
Dreyer used as few materials and colours as possible, with an emphasis on the natural quality materials, to give the house a calm and unified effect. A stand-out piece is the hanging egg chair by Nanna Ditzel and there's also built-in seating. "I find it very important to use materials honestly and the way they are meant to be. The oak floor weathers and ages over time, which is lovely," he says. "I have a background and an interest in furniture design, so I took the opportunity to design a lot of the furniture. The kitchen cabinetry is built on a concrete shell with white oiled oak doors inset into that shell. Like many Scandinavians, I have a slightly puritanical streak - I want pieces to look and feel as good after 10 years as on day one. I take the long-term approach."
9 Window onto nature
Rather than going for large expanses of glass, Dreyer opted for lots of windows in different shapes and sizes. The sunroom has pivoting glass doors, with French doors off the kitchen/living/dining area. "The design of the windows was incredibly important to the feel of the house. It comes back to location. If we were overlooking the Mediterranean, I wouldn't have hesitated to have large expanses of glass. But in the Irish climate you've got to cater for both the good and bad weather. So we went for a lot of glass in the sun room and more traditionally proportioned French doors, with smaller panes in the kitchen, living, dining room." The family enjoys spending time in the outdoor area, where they entertain when the weather allows. "The indoor/outdoor connection worked very successfully. We are lucky to have a very sheltered outdoor courtyard space," Dreyer says.
10 Think ahead
Forward planning pays off, whether it's on sustainability or future-proofing your home. "Retro-fit is complicated and expensive. You can upgrade your home's energy rating fairly easily through attic insulation or the installation of a more energy-efficient boiler, but to bring it from the standard specified 10 years ago to current best practice would be a quite expensive and complicated exercise," says Dreyer. "It's also important to design the basic rooms to such a proportion and quality that they can take change over time. The needs of toddlers to be near their parents change very quickly to teenagers wanting their own space."