Dublin hillside rebuild
tackles low energy in stages Some buildings are beyond saving, such as a south Dublin cottage which had to be knocked to deliver the first phase of a sleek new low energy home. Words: Lenny Antonelli For one family, building a low energy home in the hills of south Dublin proved to be a bit more of a rollercoaster than they anticipated. In 2010 Nick Burrett and Orla O’Shea bought a Victorian cottage in Stepaside, Co Dubin with the intention of renovating it a year or so down the line. “When we bought it, it was in a terrible condition anyway, we knew we had to do work on it,” Nick says. Both the roof and back wall were in danger of collapse. They planned to renovate the cottage and build a large extension in one go. Architect Hugh Geoghegan’s practice Archi-i was appointed to design the project, with Dublin-based Bourke Builders as contractor. “The build quality was terrible – it allowed for massive heat losses and rodent infestation,” Hugh says. And the team weren’t long on site when they got a big shock. “We were three weeks into work on site when it became clear that the fabric of the existing dwelling could not be salvaged.” The existing structure was infected with dry rot and mould, and there was substantial water damage. Pipes had frozen and cracked while Nick
and Orla were away, soaking the roof timbers. The level of damage caused by water ingress only become obvious once the builders started pulling apart the old cottage. They decided to knock the original structure and build a new cottage instead. “There was a lot of on-the-hoof design, it was quite challenging,” says Hugh. On the positive side, it gave Orla and Nick a chance to build a new, energy efficient home. What’s more, the clients had more difficulty getting a mortgage than they expected. They put plans for the extension on hold and opted to finance the rebuilding of the cottage out of their own cash reserves. The site is also on a granite hill, and the team worried they would end up having to excavate a big chunk of granite — potentially another big cost. But they wouldn’t know until the diggers were on site. Pushing the extension back and focusing on the cottage first would help to keep those groundwork costs under control should they arise. The old cottage was knocked, and work began on its replacement. The walls of the new cottage were built with concrete block, externally insulated with EPS and finished with mineral
render. The new sloping roof is insulated with 400mm of Knauf Earthwool mineral wool between and over the rafters, plus 40mm of Gutex Thermoroom woodfibre insulation fixed to OSB under this, while the flat roof is insulated with 200mm of mineral wool and 100mm of Gutex Thermoflat wood fibre. Munster Joinery triple-glazed Future Proof Passiv timber-alculad windows were installed through the property, and there are triple-glazed Velux roof windows too.