Passive house examples: cost breakdown
In this day and age anyone building or extending knows that a high level of insulation and airtightness have become practically mandatory. So we thought we’d break down the costs of two very low energy projects to show you just how much price variation there can be!
In ROI, we bring you a detached two storey designed to PassivHaus standards with a high spec finish, costing approximately €1,700 per sqm (£132 per sqft). Supplied by architectural practice MosArt, The Phoenix Centre, Block 6, Broomhall Business Park, Wicklow, County Wicklow, tel. 0404 25777, www.mosart.ie.
House size: 301 sqm / 3,240 sqft
External walls: U-value 0.15 W/sqmK; blockwork cavity wall filled with EPS beads, plastered inside and out, total width 50.5cm.
Floor: U-value 0.119W/sqmK; build up of 100mm concrete subfloor, 300mm phenolic foam insulation, 100mm cement screed.
Roof: U-value 0.112 W/sqmK; build up of natural slates, batten & counter- batten, breathable membrane, 100mm fibreboard, 250mm cellulose insulation between rafters, airtightness membrane, 50mm mineral wool, gypsum & cellulose plasterboard 12mm.
Windows: Triple glazed, argon filled, timber alu-clad, total U-value (frame and glazing): 0.8 W/sqmK, G-value: 0.55
Solar panels (hot water): Hot water demand: 5,930 kWh/year for six person occupancy; solar will supply 46% of this demand. Type installed: Vacuum tube collectors, 8 in total, collector area 6 sqm.
Heat recovery ventilation (hrv): 91.3% efficient with average air change rate of 0.29 l/hr for total volume 750m3 (2.5m ceiling height x 301 sqm house).
Professional Fees €10,000
Foundations and rising walls €25,000
Structural floor slab €10,000
Blockwork and superstructure €30,000
Roof construction and roof covering €45,000
Windows & doors €50,000
Fascia & soffit (uPVC) €12,500
First fix electrics €10,000
Insulation to floor and walls €15,000
Insulation to roof (cellulose) €5,000
External insulation to walls €11,000
Floor screed €8,500
Plastering (internal & external) €32,000
Stone cladding €10,000
Second fix electrics €15,000
Plumbing & HRV €41,000
Carpentry works to internal and external beams €12,000
Wood flooring and tiling €25,000
Kitchen and utility fit-out €27,500
Sanitaryware for bathrooms €10,000
Stairs and handrail €20,000
Painting and decorating €12,500
Rainwater goods €5,000
Utility services €5,000
Civil works/external drainage (septic tank) €20,000