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new build McNally adds: “He was pretty keen to achieve the standard, though it wasn’t an absolute requirement.” Local contractor O’Gorman Construction, who had built Quirke’s home extension at Anne Street, was appointed here. Being in a terrace, knocking and rebuilding posed obvious structural challenges. An archaeologist was also on site at this stage of the job. “During the planning and research, we found out that the ruins of Ireland's second quaker meeting house formed the walls of our site boundary, so we had an archaeologist on site during all the excavation and demolition works,” McNally says. O’Gorman Construction knocked out the ground floor of the old building, before constructing a steel frame that would support both the neighbouring buildings and the rebuilt pharmacy. Once the steel frame was up, the upper floors of the old building were demolished. “We had a very good contractor,” McNally says. “He was a great contractor we had complete faith in, he had local knowledge of the buildings on the main street in Clonmel.” The steel frame was installed on Foamglas Perinsul blocks to avoid thermal bridging between it and the concrete slab. After demolition, work began on the new building. The team looked at various options for constructing the new pharmacy, but concrete block with an insulated, ultra wide cavity proved the most cost-effective. The principle walls of the new building feature two leafs of 100mm blockwork, with a 250mm cavity insulated with bonded polystyrene bead, and Gyproc Airtite plaster internally. Cavities were also created by constructing single leaf blockwork walls 250mm from the party walls, and again insulating with bonded bead. In all cases, Ancon Teplo thermal bridge free walls ties were used to bridge the cavities. The ground floor features 150mm of Xtratherm PIR insulation board under the slab, while the timber roof is insulated with mineral wool between the rafters and in the service cavity, plus an extra layer of Gutex Ultratherm woodfibre board. Munster Joinery Alu-P Passive House Institute certified windows were specified, while the front of the shop features a glazed Batimet passive house certified triple-glazed curtain walling system, supplied and installed by PJ Bowes. The pharmacy faces south onto O’Connell Street, but the buildings on the far side of the road overshadow the ground floor facade, blocking solar gain. “The solution was to raise the shop floor ceiling height to a storey and a half and install full height glazing, so that even on the winter solstice, solar gain penetrates the store,” McNally says. Being in a terrace there was little scope for glazing on the east and west gable walls, so roof windows were installed in the single storey projection to the back to bring in more natural light. Perhaps not surprisingly on such a complex project, the biggest challenge was airtightness. During the installation of precast concrete slabs at second floor level, connecting airtightness membranes were ruptured. Because the 

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Profile for Passive House Plus (Sustainable Building)

Passive house plus issue 10 (UK edition)  

Passive house plus issue 10 (UK edition)