Leading Change in Schools Today Willard R. Daggett, CEO October, 2011.
67 Temple Avenue The reality of energy savings in retrofit Owen Daggett 25 th September 2012.
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Transcript of 67 Temple Avenue The reality of energy savings in retrofit Owen Daggett 25 th September 2012.
Role of Joseph Rowntree Foundation
Search: causes of
social problems
Demonstrate: solutions
Influence: policy and practice
POVERTY:To identify the root causes of poverty and injustice
PLACE:To support resilient communities where people thrive
AGEING SOCIETY:To respond positively to the opportunities and challenges of an ageing society
OU
R W
OR
K T
HE
ME
S
• Climate Change and Social Justice programme• Low/Zero Carbon Housing/buildings in practice
Recent and ongoing projects:
• Elm Tree Mews, New Earswick• Temple Avenue Project (Newbuild and Existing), York• Dormary Court, New Earswick• Derwenthorpe, York
JRF Search, JRHT Demonstrate & Influence
The Vision for
New Earswick
An Economically
and Socially
Sustainable
Mixed
Income
Community – but
Not
Environmentally
The Refurbishment Strategy
Step 1
• Fabric Improvements
Step 2
• Heating & ventilation system improvements
Step 3
• Measures to reduce cost of hot water and energy use
Existing Condition- Modelled Performance
Predicted Fuel Costs per Year(August 2009)Heating £612
Hot water £136
Lighting £55
Observation and Testing
Thermograms: display surface temperatures in range of colours. Can show comparative heat loss through different elements.
Air Pressurisation testing: measures permeability of building envelope to determine air tightness. Can detect leaks and air infiltration.
Co-heating testing: measures whole house heat loss (fabric + ventilation). Calculates daily heat input which provides heat loss coefficient
Heat flux sensors: measure rate of heat loss through a material to give a “real” U-value
Boroscope investigation: remote video inspection used to view building fabric voids.
Understanding the performance of the fabric
Existing Condition- Actual Performance
Measured Heat Loss324.7 W/k
Predicted Heat Loss 341.4W/k
Measured air tightness 15.76m3(h.m2)@50Pa
Leeds Met carried out measured survey, visual inspection with air pressurisation, and full SAP.
Predicted thermal performance was reasonably accurate- but underestimated performance of the dwelling.
Inaccuracies existed in the original heat loss prediction due to an incomplete knowledge of the existing building
RDSAP would not have picked up these details
Standard Retrofit- Actual Performance
Predicted Heat Loss Reduction
102.8 W/k
Measured Heat Loss Reduction75.5 W/k
Measured air tightness 9.83m3/(h.m2)@50Pa
Why the underperformance?
CWI not installed properly, or cavity “bridged”
CWI U-values not achieved: predicted target 0.45 actual target 0.70
Loft insulation at incorrect depth and not extending to eaves
Thermal bypass in chimney- even though blocked as airtightness measure
Radical Retrofit- Actual Performance
Predicted Heat Loss Reduction
234.3 W/k
Measured Heat Loss Reduction165.7 W/k
Measured air tightness 5.42m3/(h.m2)@50Pa
Performance issues
Air tightness achieved (5m3/(h.m2)@50Pa
Triple glazed windows achieved claimed U-value (0.5W/m2k)
Solid floor insulation achieved claimed U-value (0.195W/m2k)
EWI failed to meet target U-Value (0.24 compared to 0.15)
How successful were the improvements?
73%OF PREDICTED
IMPROVEMENT
STANDARD RETROFIT
71%OF PREDICTED
IMPROVEMENT
RADICAL RETROFIT
How successful were the improvements?
• Project only tested the performance of “fabric” improvements- services is a POE project
• Existing house predicted performance was dependent on accuracy of initial survey- more intrusive survey may have minimised the gap
• Predicted improvements dependent on accuracy of data entered into software. E.g., CWI uneven filling resulted in U-value gap, but after rectification a gap still existed.
• Second stage works- similar to first stage, but for EWI- discontinuities difficult to avoid around doors and entrance
How much did it cost?
£400 CWI
£550SEAL
CHIMNEY
£800
LOFT INSULATION
£3,000
AIRTIGHTNESS
£3,500
HEATING AND HOT WATER
£4,000INSULATION
AROUND GARAGE
£6,000REWIRE AND REPLASTER
£18,250STANDARD RETROFIT
£2,000
AIRTIGHTNESS
£5,000MVHR
£5,500SOLAR HOT
WATER
£6,000UNDERFLOOR INSULATION
£9,250EWI
£10,000DOORS AND WINDOWS
£37,750RADICAL RETROFIT
TOTAL NET PROJECT COST
£56k
Findings and Recommendations
Government & Regulators• If “as-built” performance does not meet design predictions, then the
Golden Rule is at risk of being broken• Green Deal assessment must consider “as-built” performance and
include tolerances in calculations of expected savings
Installers• Forensic observation and/or in-production testing should be used to
check CWI and other measures have been installed correctly• Education and training is needed to replicate experience and
knowledge
Considering the impact of the Green Deal
Findings and Recommendations
Asset Managers and residents
• Commission a comprehensive survey of the house and any alterations or replacement fittings before undertaking any improvement work;
• Consider capital and revenue cost, carbon cost effectiveness and level of disruption of potential improvements
• Seek professional advice
Considering the impact of the Green Deal
QUESTIONS, COMMENTS & OPINIONS?
Owen Daggett
Sustainability Manager
Joseph Rowntree Foundation
01904 615920
@OwenDaggett
www.jrf.org.uk