[email protected]
www.bennett.ie
(053) 9388651
Ballinakill
Ballycarney
Enniscorthy
Co. Wexford
Madeira Oaks Affordable
Passive Housing Project
Cost Analysis
(a case study)
Seamus Mullins
Quantity Surveyor
Michael Bennett Group
Case Study – Cost Definition
• Establish the additional construction cost of
building a Certified Passive House of similar
design to an already constructed BER A3 rated
House on our site at Madeira Oaks,
Enniscorthy, Co. Wexford.
• Establish affordability for the house purchaser.
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Case Study – Cost Definition
• No building elements other than those
containing a passive aspect have been examined.
• No overheads or profit margin have been
included in the analysis.
• VAT has not been added on to the final figure.
• All costs figures quoted are at current values.
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Case Study -Exclusions
• Land Cost
• Site Preliminaries (site overheads)
• Finishes and Fitments
• Personal Choice Items
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Building Description Comparison
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•
•
•
•
Both houses are traditional semi-detached design
Both are typical 3 bedroom two storey houses
The thermal envelope of both is timber frame
The floor area is 102m2 (1,100sq.ft. approx.)
Triple glazed windows are proposed for the new
Passive House, and were also installed in the as
build A3 house. However, the Passive House
windows are Certified Passive.
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Building Description Comparison
• Space heat demand, and heat load values are much
lower in the Passive House.
• Structural air tightness of less than 0.60 hˉ ¹ will be
achieved in the Passive House. An air leakage of
1.66 hˉ ¹ was achieved in the A3 house.
• U-values ;
A3 Ground Floor - 0.16W/m2K (Passive -0.09W/m2K)
A3 External Walls - 0.23W/m2K (Passive – 0.17W/m2K)
A3 Roof Space – 0.14W/m2 K (Passive – 0.08W/m2K)
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Existing A3 House
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Case Study Cost Analysis
Building Cost
Affordability
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1. Substructure
• Additional insulation
detailing at the junction of
the external wall and the
floor slab.
• Increased insulation
thickness under the
general area of the floor
slab.
Extra Over Cost
€315.00
€787.00
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2. External Wall
• Wider and heavier wall
structure.
• Greater insulation thickness.
• Improved cold bridging.
• Increased measures to deal
with interstitial
condensation, air tightness,
and wind tightness.
Extra Over Cost
€2,150.00
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3. Roof Structure
• Structural design changes.
• Greater insulation thickness.
• Increased measures to deal
with interstitial
condensation, air tightness,
and wind tightness.
Extra Over Cost
€680.00
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4. Windows and External Doors
Extra Over Cost
• Supply and installation.
€304.00
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5. Space Heating System, and
Renewable Technologies
• Omit the following ;
a) Oil fired heating system (boiler
and radiators).
b) Solar Panel Installation
c) MHRV
d) Wood burning Stove.
e) Chimney Stack
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5. Space Heating System, and
Renewable Technologies
Extra Over Cost
• Add back the following ;
a) Nilan Unit
b) Photovoltaic Panels
€1,035.00 cr.
Note; Secondary Heating is
provided – 1.35Kwatts(max.)
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6. Passive House Certification
Extra Over Cost
• Irish Passive House
Academy Certification Fee.
• Technical support on site
in supervising the works.
€540.00
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7. Door Blower Test
• Passive House door
blower test requires a
different methodology,
and the air tightness
requirement is far greater
than our current building
standards.
• BER testing is also
required for compliance
purposes.
Extra Over Cost
€340.00
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Cost Analysis Summary
1.
2.
3.
4.
5.
6.
7.
Substructure
External Wall
Roof Structure
Windows and External Doors
Space Heating System, and
Renewable Technologies
Certification & Technical
Door Blower Test
€1,102.00
€2,150.00
€680.00
€304.00
€1,035.00
€540.00
€340.00
€4,081.00
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Madeira Oaks Affordable
Passive Housing Project
Case Study
Thanks for your attention!
Seamus Mullins
Quantity Surveyor
Michael Bennett Group
[email protected]
www.bennett.ie
(053) 9388651
Ballinakill
Ballycarney
Enniscorthy
Co. Wexford