WEATHERPROOFING SOCIAL HOUSING IN AN URBAN ENVIRONMENT THROUGH RETROFITTING: A HOLISTIC APPROACH

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1 13th February 2014 Retrofitting Cities for Tomorrow s World 2014 Conference Cardiff, UK Image credits: bit.ly/1oa24sc WEATHERPROOFING SOCIAL HOUSING IN AN URBAN ENVIRONMENT THROUGH RETROFITTING: A HOLISTIC APPROACH Dr Anna Mavrogianni The Bartlett School of Graduate Studies, UCL

2 OVERVIEW Background Methods Results Discussion A warming climate Housing stock transformations Unintended consequences Social housing Household survey Indoor temperature monitoring Indoor temperature modelling Indoor air pollution modelling Case study buildings Indoor temperature monitoring Indoor temperature modelling Indoor air pollution modelling Key findings Further research Relevant publications Image credits: bit.ly/1arwk25 Image credits: bit.ly/1g3clhl

3 BACKGROUND A WARMING CLIMATE Future projections Our climate is changing due to humanmade greenhouse gas emissions. Overheating in cities will be exacerbated due to the urban heat island effect. Source: LUCID project 2080s, Medium Emissions scenario Source: UKCP09

4 BACKGROUND HOUSING STOCK TRANSFORMATIONS The facts 80% UK legally binding decarbonisation target by % of UK energy consumed in dwellings 85% of existing dwellings will still be standing in the 2050s only 1% of which have adequate thermal performance The challenge eradication of fuel poverty smart meters in all UK homes, whole house retrofit package to 7 million houses implementation of all cost effective measures 1+ home fully retrofitted every minute for the next 10 years! zero carbon stock?

5 BACKGROUND UNINTENDED CONSEQUENCES Source: Shrubsole S, Macmillan A, Davies M, May N. 100 unintended consequences of policies to improve the energy efficiency of the UK housing stock. Indoor and Built Environment. In print.

6 BACKGROUND SOCIAL HOUSING Triple jeopardy mapping Vulnerable residents (elderly 65+, low mobility, chronically ill, low income individuals) Vulnerable buildings (1960s-70s, top-floor, south-facing, single-sided ventilated, purposebuilt flats) Vulnerable locations (urban heat island hotspots ) Impacts on entire communities and infrastructure

7 METHODS HOUSEHOLD SURVEY Climate Resilience Islington South Project (CRISP) DEFRA-funded through Cities Climate Adaptation Grant Individual and community resilience to extreme weather events amongst older people in south Islington Survey of 1,000 vulnerable households Exploring attitudes, knowledge, adaptive capacity, barriers Key findings Overheating risk considered an issue despite some scepticism Adaptive capacity Low awareness of flood risk

8 METHODS CASE STUDY BUILDINGS Project area 1960s high-rise 1960s high-rise 1900s mid-rise 1950s mid-rise

9 METHODS MONITORING AND MODELLING Monitoring HOBO U data loggers Dry bulb air temperature and relative humidity Living rooms and bedrooms 8 flats 5-minute intervals July to September 2013 Modelling 2 levels of building fabric efficiency levels (as built and retrofitted) 2 types of window and shading operation (daytime rapid ventilation vs. night time purge cooling combined with daytime shading) UKCP s climate change scenarios

10 RESULTS TEMPERATURE MONITORING Current temperature profile and overheating assessment based on different criteria

11 RESULTS TEMPERATURE MONITORING Outdoor-indoor temperature relationship

12 RESULTS TEMPERATURE MODELLING Future temperature profile for different fabric efficiency levels and building operation scenarios

13 RESULTS INDOOR AIR QUALITY MODELLING Future indoor-oudoor PM 2.5 ratio for different fabric efficiency levels and building operation scenarios

14 DISCUSSION KEY FINDINGS Retrofit should be driven not only by mitigation targets but also by adaptation needs. Poorly thought out retrofit is likely to lead to unintended consequences, such as summer overheating. Occupant behaviour is a significant determinant of indoor extreme heat and pollutant exposure risk. Training occupants post-retrofit is crucial. Image credits: bit.ly/1imdcrl

15 DISCUSSION FURTHER RESEARCH Temperature monitoring across a larger housing sample Development of coupled indoor thermal and air quality building stock model for England as part of the NERC-funded AWESOME project Combining individual building models with microclimatic modelling software (ADMS or ENVI-met) to examine the impact of urban landscape interventions in the area surrounding the estates Source: LUCID project Source: ENVI-met

16 DISCUSSION RELEVANT PUBLICATIONS Mavrogianni A., Wilkinson, P., Davies, M., Biddulph, P., Oikonomou, E., Building characteristics as determinants of propensity to high indoor summer temperatures in London dwellings. Building and Environment, 55: pp Oikonomou, E., Davies, M., Mavrogianni, A., Biddulph, P., Wilkinson, P., Kolokotroni, M., The relative importance of the urban heat island for overheating in London dwellings versus the thermal quality of the buildings. 57: pp Mavrogianni A., Davies M, Taylor J., Raslan R., Oikonomou E., Biddulph P., Das P., Jones B., Shrubsole C. Assessing heat-related thermal discomfort and indoor pollutant exposure risk in purpose-built flats in an urban area. CISBAT - International Conference on Clean Technology for Smart Cities and Buildings, EPFL Lausanne, 4th-6th September 2013, Lausanne, Switzerland: CISBAT. Mavrogianni A., Davies M, Taylor J., Raslan R., Oikonomou E., Biddulph P., Das P., Jones B., Shrubsole C. The unintended consequences of energy efficient retrofit on indoor air pollution and overheating risk in a typical Edwardian mid-terraced house. FutureBuild International Conference, University of Bath, 4th-6th September 2013, Bath, UK: FutureBuild. Kolm-Murray, J., Smith, A., Clarke, C., Individual and community resilience to extreme weather events amongst older people in south Islington: attitudes, barriers and adaptive capacity. London, UK: Islington Council. Mavrogianni, A., Davies, M., Taylor, J., Chalabi, Z., Biddulph, P., Oikonomou, E., Das, P., Jones, B., The impact of occupancy patterns, occupant-controlled ventilation and shading on indoor overheating risk in domestic environments. Building and Environment. Under review. Taylor J., Davies M., Mavrogianni A., Chalabi Z., Biddulph P., Oikonomou E., Das P., Jones B., The relative importance of input weather data for indoor overheating risk assessment in London dwellings. Building and Environment, Under review. Mavrogianni, A., Taylor, J., Thoua, C., Davies, M., Kolm-Murray, J., A coupled summer thermal comfort and indoor air quality model of urban high-rise housing. 8 th Windsor Conference: Counting the Cost of Comfort in a changing world Cumberland Lodge, etwork for Comfort and Energy Use in Buildings (NCEUB), April 2014, Windsor, UK: NCEUB. Under review.

17 Thank you! Any questions? Image credits: bit.ly/1ogsxnx