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67 Temple Avenue. The reality of energy savings in retrofit. Owen Daggett 25 th September 2012. Role of Joseph Rowntree Foundation. POVERTY: To identify the root causes of poverty and injustice. Search: causes of social problems. PLACE:
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67 Temple Avenue The reality of energy savings in retrofit Owen Daggett 25th September 2012
Role of Joseph Rowntree Foundation POVERTY: To identify the root causes of poverty and injustice Search: causes of social problems PLACE: To support resilient communities where people thrive Influence: policy and practice OUR WORK THEMES AGEING SOCIETY: To respond positively to the opportunities and challenges of an ageing society Demonstrate: solutions
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 Starting Point Insert p6
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 Loss 324.7 W/k Measured air tightness 15.76m3(h.m2)@50Pa Predicted Heat Loss 341.4W/k 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 works Decent Homes…..Plus
Standard Retrofit- Actual Performance Predicted Heat Loss Reduction 102.8 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 Measured Heat Loss Reduction 75.5 W/k
Radical Retrofit works Aiming for an 80% CO2 reduction
Radical Retrofit- Actual Performance Predicted Heat Loss Reduction 234.3 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) Measured Heat Loss Reduction 165.7 W/k
How successful were the improvements? 71% OF PREDICTED IMPROVEMENT RADICAL RETROFIT 73% OF PREDICTED IMPROVEMENT STANDARD 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
32% 69 Temple Avenue
How much did it cost? £800 £3,000 TOTAL NET PROJECT COST £56k £400 CWI £550 SEAL CHIMNEY LOFT INSULATION £18,250 STANDARD RETROFIT AIRTIGHTNESS £4,000 INSULATION AROUND GARAGE £6,000 REWIRE AND REPLASTER £3,500 HEATING AND HOT WATER £2,000 £5,000 MVHR £5,500 SOLAR HOT WATER £37,750 RADICAL RETROFIT AIRTIGHTNESS £10,000 DOORS AND WINDOWS £9,250 EWI £6,000 UNDERFLOOR INSULATION
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 Owen.daggett@jrf.org.uk @OwenDaggett www.jrf.org.uk