Rosslare Passive House Scheme - 38

Ireland has woken up to the Passive House. Seven years ago Tomas O’Leary built Ireland’s first certified passive house in Wicklow – a home that showed Germanic influences in looks as well as energy performance. A new development at Grange Lough, Rosslare, reveals that passive can be made Irish – both in terms of what they’re built with, and how they look. Grange Lough in Rosslare, Co Wexford is the country's first commercial passive house development, and as such it's a landmark in the story of Irish construction. This is the first time that a speculative developer has looked at the market and decided it wanted passive houses. Not only that, but the scheme represents perhaps the most Irish take on the passive house you'll find. Its design is traditional- it does not look German, and incorporates much of what you'd expect in an Irish house, even a chimney. Most especially however, it has been built using Irish products and Irish expertise.

The design team is Irish, the developer is Irish, the thermal envelope manufacturer is Irish, the company which is certifying the house as passive is Irish, and almost all of the technol­ogy used in the house - including the windows and doors - is Irish.

"The passive house is a German concept but I think it's very important to localise it," says passive house guru Tomas O'Leary, director of MosArt and founder of the Irish Passive House Academy. "In Rosslare, they decided from the very outset that they wanted a fireplace and they weren't willing to roll over and accept no for an answer. You really wouldn't know it was a passive house walking around. It's traditional and I don't mean twee by traditional- it's just got a lot of the components that Irish people like."

There are three separate forces behind this project - developer Michael Bennett, Donal Mullins of Shoalwater Timber Frame who de­signed and fabricated the thermal envelope, and low energy designer Seamus Mullins of Seamus Mullins and Co. Both Donal Mullins and Michael Bennett have been building tim­ber frame houses for the past decade, while Seamus Mullins has provided much of the de­sign know-how. He recently completed the certified passive house designer course with the Irish Passive House Academy. Throughout their working relationship, the team has grad­uated to incrementally more efficient homes. The day we met in Rosslare, Bennett was fi­nalising the sale of an A3 rated house in another of his developments in Enniscorthy.

With rising energy prices and the recession fo­cusing minds on the energy performance of their homes, Bennett believes that the time is right for this kind of development. But location is also vital- Rosslare Strand has long been a summer holidaying Mecca. "We won't have first time buyers here," says Bennett, adding that the first house in the development carries a price tag of €490,000. "We'll have I expect retiree-type clients, with maybe an odd one re­turning from overseas, but as the houses are three and four bedroom, we are also catering for families and permanent residency." Given this profile, it was always vital that the house wear its passive tag lightly. "The Irish are very slow to change," he says. "If you built a state of the art glass house, would you sell it to any­one? I don't think you'd have a hope. People would come and look at it and ooh and ahh over it but they wouldn't buy it."

Giving the house a traditional look isn't all about meeting the market's aesthetic expec­tations. Irish houses need to be designed to cope with Irish conditions. "We've higher wind-speeds than mainland Europe, it's not as cold but we've more rainfall," Seamus Mullins explains. "The moisture levels mightn't impact so much on the thermal efficiency of the house but it will impact on the quality of the build. The detailing in Europe stands up in Europe but when it's put into wind-driven rain situa­tions; suddenly you're going to start getting leaks." Moreover, the design incorporates ele­ments of Irish design that have always made sense. The draft lobby, for example, is a stan­dard feature of many of the houses in the area.

There will eventually be eight houses in Grange Lough, which is a very private wall en­closed site. "There will only ever be one house for sale here at a time," says Bennett. The de­sign and construction team have however been very careful to ensure that early arrivals won't be living on a building site. All services and preparatory work for the eight houses are in place, all footpaths and roads have been constructed, while sites due to begin later are now landscaped and will remain so until con­struction can begin. Come construction time, the houses will be built behind hoardings, and as Seamus Mullins is quick to point out, the en­hanced sound insulation of a passive house means noise is unlikely to be an issue.

The first challenge facing Seamus Mullins was achieving the right orientation for eight houses on an elongated, restricted site. "If you haven't got a front elevation facing south, you've a rear elevation facing south," he says. "So it's a matter of changing the internal room layout. Nearly all of the four designs have a central core around the stairwell that faces south." Glazing to the west had to be amended due to over­heating issues turned up by the PH PP software. The houses themselves are not large by recent standards - the designs vary between 1,860 square feet and 2,200 square feet. "They're not large," says Mullins. "That's an important aspect as well, because to comply with passive certification there's a ratio of floor area of around 35m2 per person ... That's to try and get a better use of land, money and space." When he began his timber frame business eleven years ago, Donal Mullins of Shoalwater set out to ensure that any work that could be done in the factory was done in the factory. In order to preserve quality and continuity, the team that manufacture the frames also erect them onsite. He says that when he began building timber frame houses almost thirty years ago, the first panel taken from the back of the lorry was always the last to be used, and invariably suffered from constant handling. Bearing this in mind, Mullins developed a process of packaging the building system in bales and, and loads it to ensure minimal handling. "The first panel you take off should be the first panel you use." He says.Extreme attention to detail has been the hall­mark of the build. Achieving passive certifica­tion was vital to the commercial success of the project, says Bennett. "We had to be certain of our certification before we started. Anyone starting to build a house like this without their homework done and all their planning and all their issues addressed are on a hiding to noth­ing. There's no way can you get passive certi­fication without it." To facilitate this, the house was built on paper long before a sod was turned onsite. Because of all that preparatory work, says Donal Mullins, the construction stage didn't throw up any real stumbling blocks. "I wouldn't say there were huge issues during the build," he says. "The big issues were in the learning curve itself. Because of all the work we had done previously, we had a base of knowledge to build from." All three have been continually attending seminars and conferences in order to up-skill and keep abreast of best practice.

Achieving and then keeping airtightness is of course the perennial bugbear of low energy construction. It helped in Grange Lough that no subcontractors were used, and that many of the trade’s people had been working with Bennett for more than a decade. "If you don't bring your trades people along with you, if you don't educate them, if they don't know what they're trying to do, how in the hell can they work towards it?" says Michael Bennett. "We've done a lot of work on our people here."

Responsibility for achieving airtightness in the first place fell to Shoalwater, who have won an excellent reputation for themselves in this field using the Pro Clima system of membranes, tapes and adhesives. "When we were finished, we did our first blower door test," Mullins ex­plains. "We got an air change rate of 0.51 [ACH at 50 Pa]. That was very good. Then Michael could go and say to his electrician, his plumber, this is our airtightness, this is what you have to have when you guys are done. If it goes up, it's because of something you guys did. Now they're far more conscious and far more care­ful." A blower door test after each phase not alone kept tabs on how the air change rate was being maintained relative to the passive house standard of 0.6, but also revealed who was re­sponsible if the number went up.

One key issue that arose was with the Stovax stove. The blower door test immediately fol­lowing the installation of the stove drove the air change rate above the 0.6 threshold. Re­peat visits from Stovax improved the door sealing, which is where the problem lay, and moved the rate back down to acceptable levels. Surprisingly, the unit is still not a room-sealed unit. Though most of the air required from combustion is piped in externally, a small pro­portion is still taken from room air.

A potential issue also arose with the Beam cen­tral vacuuming unit. Though bin and turbine are both located within the sealed envelope, air could theoretically have escaped through an extract pipe which terminates outside the house. "We could have had a problem there," says Seamus Mullins, "but we were never going to find out if we didn't put it in. From a clean­ness and dust elimination point of view, the central vacuuming system is superb. The filtering system really fits with the passive principle in that you're creating this quality comfortable living environment." The solution which Beam came up with was a motorised valve, kept shut while the unit is not in operation, and triggered to open when switched on. The blower door test however u

ncovered no leakages in the system so the valve was not fitted.

The windows are from Munster Joinery's Fu­ture Proof range. "Passive house windows gen­erally cost people about €650 a square metre:' says Brendan Harte of the company.”We wanted to bring the price down, we wanted to put value for money into the market but still achieve the passive house standard. The glass section is 52mm triple-glazed and the PVC pro­file that we went with in Rosslare is a 90mm section, fully foam-filled all the way through." Two Munster Joinery windows are currently with the Passive House Institute in Darmstadt undergoing certification. The Passive House In­stitute was heavily consulted during research and development of the window range to en­sure that the onerous certification requirements would be met. The windows are the first Irish products submitted to the institute for certifi­cation. "I think that's very exciting because windows typically are the most expensive ele­ment in the passive house:' says Tomas O'Leary.”They're often imported and I think in these times, if we can generate local employment in construction, that's better for everyone."

"People are amazed when they hear that the windows are Irish, says Seamus Mullins.”Peo­ple think we should have Austrian or maybe German windows, we shouldn't have Irish win­dows, and are surprised to hear of the product range advancements that Munster Joinery have made." But using local products isn't just about local pride, says Donal Mullins. ''That window is a brilliant window and we can get it in Ire­land in a two week delivery date. It's so much easier to run a schedule when your window manufacturer can have them in ten days to two weeks, at this quality and with an Irish fit­ter. You've got any kind of little latch or lock problems, you ring him up and the serviceman is here." One of the most interesting findings of the project was in relation to cost. Seamus Mullins tracked expenditure throughout, and pre­sented a paper at the SEAl See the Light con­ference in Croke Park last September. He found that the cost of upgrading a project from A3 to passive came in at 02 per square foot. "That's in our first attempt:' he says.”We should be able to pull that down." The Grange Lough house is currently awaiting confirmation of its BER, which Seamus has calculated at high A3. He refers to Bennett's A3 house, just sold in Enniscorthy. "The funny thing is both the pas­sive house and the Enniscorthy house are A­-rated. In Rosslare, the running costs for all your heating and hot water, are going to be in the region of €500 - €600 a year, on the basis of an energy demand of 10 kWh/m'/a, while in En­niscorthy, the A3 rated houses is going to have an energy requirement of 67 kWh/m'/a - which is approximately six times more. It might not be six times more expensive to heat, but if it's three times more expensive, that means the Enniscorthy purchaser is spending an extra 0,500 to 0,800 a year for the life of that house."In order to meet the passive house standard, the house must be designed to have an annual heating demand of not more than 15 kWh/m'/yr. In Rosslare, the calculations are coming in at 10 kWh/m'/yr, 33% below the standard. Michael Bennett explains that they needed to aim high in order to provide sufficient comfort to ensure that certification would be achieved. "But we're going to get better at this, and more efficient at it:' he says. Being the first passive house in the scheme, everyone involved in­vested a huge amount of time and effort in achieving the right results. Bennett sees this time as an investment in skills and experience, and believes that from here on in, each house will go up within three months.

These houses are finished with the high end of the market in mind, but Bennett believes that it's entirely possible to provide the same qual­ity of build for the lower end. "I would hope, if not this year then in two or three years down the road we'll be starting a small scheme some­where. Ten or twelve houses, and they'll be 'white deal passive', to give passive certified houses to entry level buyers." Donal Mullins agrees. "Why not get into a position where we can supply passive houses at affordable prices to the county councils?"