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 OUR WORK THEMES

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 Challenge?

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

The Starting Point Insert p6

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 Loss W/k Predicted Heat Loss 341.4W/k Measured air tightness 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 W/k Measured Heat Loss Reduction 75.5 W/k Measured air tightness 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 works Aiming for an 80% CO2 reduction

Radical Retrofit- Actual Performance Predicted Heat Loss Reduction W/k Measured Heat Loss Reduction W/k Measured air tightness Performance issues Air tightness achieved 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

32% 69 Temple Avenue

How much did it cost? £400 CWI £550 SEAL CHIMNEY £800 LOFT INSULATION £3,000 AIRTIGHTNESS £3,500 HEATING AND HOT WATER £4,000 INSULATION AROUND GARAGE £6,000 REWIRE AND REPLASTER £18,250 STANDARD RETROFIT £2,000 AIRTIGHTNESS £5,000 MVHR £5,500 SOLAR HOT WATER £6,000 UNDERFLOOR INSULATION £9,250 EWI £10,000 DOORS AND WINDOWS £37,750 RADICAL 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