Passive ways to save when designing new house builds

With passive house design going beyond the current legislative controls, there have been calls for Ireland to adopt the low-energy model as the national standard for new buildings, writes FRANK McDONALD,Environment Correspondent

IRELAND HAS the potential to be a world leader in passive, low-energy house design, creating exports and jobs while at the same time meeting its targets under the Kyoto Protocol on Climate Change, according to architect Martin Murray.

Murray is chairman of the Passive House Association of Ireland, a voluntary body committed to promoting low-energy passive house design across all building types – and he says it’s thriving despite, or perhaps even because of, the plight of the construction industry.

Passive house design goes beyond the current legislative controls represented by BER (Building Energy Rating) and DEAP (Dwellings Energy Assessment Procedure), and the association wants Ireland to adopt the passive house as the national standard for new buildings.

The term “passive house” refers to a more rigorous standard for energy efficiency in a building, whether it’s a house or otherwise, to minimise its ecological footprint. It results in ultra low-energy buildings that require relatively little expenditure on space heating or cooling.

And they don’t need to be wacky and unconventional, with a grass roofs and micro-generator wind turbine. Buildings built to the passive house standard can look like any other – the trick is how they’re built, to ensure that their energy performance over time is second to none.

It’s also an indication of the trend internationally that Jeff Colley’s Construct Ireland magazine, bible of the sustainable building sector, has just relaunched itself as Passive House Plus with the aim of increasing its circulation in Britain as well as in Ireland.

At the recent 10th anniversary See the Light conference, enthusiasts learned about the Brussels experience of moving towards the internationally recognised passive house design standard from 2015 onwards, as the latest step in improving energy conservation.

Joke Dockx, an engineer from the Brussels municipal environment and energy department, stressed the need to promote and “prove the legitimacy” of the standard to both the general public and also to contractors and developers – aided by a grant of €100 per sq metre.

Brussels faces many challenges in promoting this strategy. A large proportion of buildings in the city centre are protected, tightly urban in nature and in multiple use – issues that would arise if the standard was to be implemented in Dublin, a city of similar size.

Dr Paul Butler, of Enterprise Ireland, spoke about the need to address our “significant exposure” to imported oil, gas and coal, which are currently costing €6.5 billion annually – a bill that could be reduced significantly if the passive house design standard was adopted.

Tomás O’Leary, of MosArt Architects, told the conference about his company’s efforts to promote passive house design in the United States from their base in Wicklow – supplying passive-standard windows into a market that’s growing, thus proving the export potential.

O’Leary built Ireland’s first certified passive house in 2004. Although large (at 350 sq metres), it costs only a few hundred euro a year to run at a very comfortable level, mainly for the wood pellets and power to the pellet stove, circulation pumps and heat recovery ventilation.

According to Martin Murray, “Ireland now leads the English-speaking world in experience and know-how of passive design.” The Fás training centre in Finglas, designed by Scott Tallon Walker, is claimed to be the world’s first “passive house educational facility for tradespersons”.

The train drivers’ canteen and changing facility at Iarnród Éireann’s rail depot in Portlaoise, designed by David Hughes, also achieved passive house certification, as did new houses in Wicklow, Kilkenny and Cork by architects Sam Mayes, Martin Mulligan and John Moorehead.

Other trailblazers include a refurbishment project at Cork Institute of Technology, energy-sensitive urban planning by Reddy Architecture and two new primary schools in Moynalty, Co Meath, and Enniskerry, Co Wicklow, which were both designed to passive house standard.

Most impressive of all is UCD’s new Roebuck student residence, a six-storey building by Kavanagh Tuite Architects, which is one of the largest such passive house projects in Europe. It was designed to achieve energy savings of 55 to 60 per cent over its lifetime.

Dr Shane Colclough told the See the Light conference about a new passive house laboratory at the University of Ulster, where equipment, products and software can be tested; its “artificial solar array” can replicate any sunny day of the year in Ireland in energy terms.

John Moorehead complained that existing BER software is neither sensitive to location or even orientation and takes no account of the many climatatic zones in Ireland.

Indeed, just one climate monitoring station at Dublin Airport underpins the current BER regime.

“It is clear that the current building regulations are not yet close to passive house standards and that they will continue to be stymied due to the continued acceptance of poor air-tightness standards – usually reflecting poor workmanship and design integration,” Murray said.

He also complained about an over-reliance on renewables to achieve ostensibly high A ratings for poor “low energy’” buildings. “The anomaly of very low energy buildings specifically having to ‘over supply’ themselves with renewables was greeted with disbelief,” he said.

There will be a Passive House Open day on the weekend of November 9th to 11th. Further information online at phai.ie