Principal Investigator: Prof Li Shao De Montfort University

1. Choosing adaptation interventions – the whole is greater than the sum of its partsAdapting UK dwellings to reduce overheating during heat waves Principal Investigator: Prof Li Shao De Montfort University Co-Investigator: Dr Chris GoodierLoughborough University Researcher: Stephen Porritt De Montfort University

2. 2010: cooler Britain; warmer world 2010 in UK • Coldest year since 1986 • Coldest December on record

3. 2010: Colder Britain; Hotter World 2010 Globally – (2nd) warmest • Met Office • NOAA • NASA Extreme weather

4. PP1 – Aim • Assess and rank passive adaptations for common UK dwellings to reduce overheating during heat waves

5. Building on previous work

6. Dwelling Selection & Construction Details Cross-referenced with English House Condition Survey and Energy Saving Trust databases Modern Detached 1930s Semi Victorian Terraced 1960s Flats

7. Adaptations (Interventions) • Increased loft insulation • Internal wall insulation • External wall insulation • Cavity wall insulation • Internal blinds • Curtains • External shutters • Fixed shading over windows • Solar reflective walls • Solar reflective roof • Changing window opening rules • Night ventilation by opening ground floor windows • Low-e triple glazing

8. Weather data • Three Approaches considered: • Morphed future weather files Based on UKCIP02 • Mediterranean weather files (Milan, Rome etc.) • Real heat wave years from the UK (e.g. 2003)

9. Ranking: Overheating exposure of dwelling types • 1960s top floor flats • 2007 detached • 1930s semi • Ground floor flats • end terraced • mid terraced Implication for the elderly:

10. Result: Single Adaptation Example

11. Result: Single Adaptation Example

12. Result: Single Adaptation Example

13. Findings: Single adaptations • External shutters are the single most effective intervention (typically 50% reduction of overheating) for 3 of the 4 house types • The exception is the terraced (due to solar heat transmission through solid walls. Light walls (and external insulation) are better • The value of behavioural (zero cost) adaptations

14. Combined Adaptations • The limitation of single adaptation ranking • Challenges for assessing combining adaptation • Computation • Analysis • Making resultsavailable to others 8192 Simulations (94,208 total)

15. Combined Adaptations Example

16. Combined Adaptations Example

17. Combined Adaptations Example

18. Combined Adaptations Example

19. Combined Adaptations Example

20. Findings: Combined Interventions Semi, terraced & ground floor flats • Overheating can be eliminated using the passive adaptations • Low-cost adaptations often lead to greater winter energy use • Many adaptations could reduce winter energy use by over 40% • Use toolkit to pick

21. Semi, terraced & ground floor flats Cost/Performance • Or • £10k for • 95% reduction of overheating • 40% reduction of winter energy Typical cost example for a Semi : • £3k • 85% reduction of overheating • 20% reduction of winter energy use Similar costs for terraced and G floor flats

22. Top floor flats & 2007 Detached:“harder to treat” • Overheating exposure could not be eliminated • Costs many times higher for same level of overheating reduction • 2007 detached: hard to reduce winter energy use £23k for detached vs £3k for semi

23. Top floor flats & 2007 DetachedAdaptation cost increases for elderly Top floor flat: • £13k daytime unoccupied (family) • £17k for daytime occupied (elderly) • overheating reduced to similar level • similar reduction of winter energy use • 2007 Detached: • Similar cost increase for elderly • In contrast to semi, terraced, G floor flats: • Insignificant cost difference

24. Q: 2007 detached overheats.What if a terraced is highly-insulated like a 2007 detached? A: For comparison, 2007 detached house worst overheating exposure: 715 DH Essentialto Integrate adaptation with mitigation in retrofit design, and new build, encouraged by policy

25. PP1 – Retrofit web toolkit Web tool demonstration Stephen Porritt

26. PP1 – Thank You Retrofit web toolkit: Questions or comments: Stephen Porritt: Li Shao: www.iesd.dmu.ac.uk/crew sporritt@dmu.ac.uk lshao@dmu.ac.uk

27. Ground vs top floor flats • Very different adaptations for different floors • Use toolkit to pick compatible adaptations

28. External vs Internal Insulation • External insulation consistently outperforms internal insulation • internal insulation could lead to worse overheating in some cases • internal insulation has a role to play if combined correctly with other interventions (use the toolkit)

29. PP1 – Summary • Large range in overheating exposure, for example: • Dwelling type: Top floor flat over 4x mid terraced house • Orientation: Mid terraced house west-facing living rooms 3x north-facing living rooms • Occupancy: Detached house daytime occupied 2x daytime unoccupied • Best adaptation is often external shutters, though solar reflective coating on the walls is more effective for the end terraced house • Some dwellings can be treated effectively at moderate cost (ground floor flat, terraced houses). Others are much more expensive to treat and overheating cannot be totally eliminated at any cost (modern detached, top floor flat)

30. PP1 – Summary • If older houses (e.g. terraced) are retrofitted for reducing carbon emissions without considering summer use, overheating will increase to that of modern houses and they will be harder to treat • Overheating exposure can be significantly greater for residents who have to stay at home during the daytime (e.g. elderly or infirm) • Elderly and infirm residents should not, where possible, be housed in the most vulnerable dwellings (e.g. top floor flats)

31. PP1 – Summary • Validation monitoring has been carried out in addition to the simulations and construction of the web toolkit • Rigorous selection of dwelling types, baseline construction and insulation for simulation models • Selection of weather data – 2003 heat wave is expected to be an every year event by the 2040s • Single adaptations provide an insight, but combined adaptations show how overheating AND energy use can be reduced • Adaptation and Mitigationmust be considered together • The retrofit toolkit can be used to: • Evaluate stock • Prioritise retrofit schedule • Select adaptations and compare different solutions