IN DETAIL
Building type: Detached 272 sqm cavity wall house with 42 sqm integrated double garage within thermal envelope Budget: €306,203 gross (excludes some client finishes) Passive house certification: Not certified Space heating demand (PHPP): 9 kWh/m2/yr Heat load (PHPP): 10 W/m2 Primary energy demand (PHPP): 91 kWh/m2/yr Overheating (% of time over 25C in PHPP): 0.0% Heat loss form factor: 2.87 Indicative BER: A3 (56.51 kWh/m2/yr) - excluding trace wire energy use Energy performance coefficient (EPC): 0.389 Carbon performance coefficient (CPC): 0.366 Airtightness (at 50 PA): 0.58 ACH or 0.97m3/m2/hr Energy bills: Average annual electricity bill of
€900 including VAT and standing charges. Heating costs: Estimated at €220 based on PHPP-calculated space heating demand at assumed night rate electricity tariff of 9c per kWh. Thermal bridging: Proprietary Supergrund (now Kingspan) insulated passive foundation / floor system to form ground floor slab & foundations, proprietary TeploTie low thermal conductivity cavity wall ties, thermally broken window frames, insulated rigid insulation cavity closers to all reveals. Y-value: 0.08 W/mK (based on ACDs and numerical simulations): Ground floor: Kingspan insulated passive foundation / floor system incorporating 300mm structural EPS insulation under slab with min 100mm structural EPS wrapped around foundation ring beams. U-value: 0.11 W/m2K Walls: 25mm white sand-cement rendered finish externally, followed inside by 100mm concrete blockwork outer leaf, 300mm cavity fully insulated with proprietary Ecobead platinum grade EPS cavity bead insulation with max. conductivity of 0.035W/mK. TeploTie
low conductivity wall ties suitable for 300mm cavity, 100mm concrete blockwork inner leaf with 15mm plaster finish internally including airtight scratch coat. U-value: 0.11 W/m2K Roof: Natural slate finish externally on 50x35 battens / counter battens, followed underneath by breathable roofing underlay, 225mm timber rafters insulated with 220mm Isover Metac insulation (with max 0.035W/mK thermal conductivity) breathable airtightness / vapour control membrane, 50mm insulation backed plasterboard ceiling. U-value: 0.14 W/m2K Windows: Passive House certified Munster Joinery Ecoclad 120+ triple glazed aluminiumclad windows, with argon filling and an overall U-value of 0.85 W/m2K installed. Heating: 60 tube Joule solar thermal system with 3.62KW output, supplying underfloor heating and 500 litre solar cylinder plus immersion heater. Ventilation: Dantherm HCH 8 heat recovery ventilation system, Passive House Institute certified to have heat recovery rate of 95%.
CONSTRUCTION IN PROGRESS
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1 The Kingspan insulated passive foundation system, incorporating 300mm structural EPS insulation under slab, practically eliminates the critical wall-to-floor thermal bridge; 2 the house features 200mm wide masonry cavity walls with full-fill platinum bead insulation; 3 the Isover Vario airtightness and vapour control membrane installed to the underside of the roof structure.
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