Tackling Hard-to-treat homes

1. Tackling Hard-to-treat homes Heat pumps, solid wall insulation and non-traditional construction

2. Energy Efficiency Partnership for Homes Three research exercises commissioned by the Hard-to-treat homes sub-group: • Solid Wall Insulation: Impetus, 2004 • Heat Pumps: People for Places, 2005 • Non-traditional construction: CSE, 2005

3. Fuel poverty and non-traditional construction Ian Preston, CSE Dr Richard Moore

4. Background • ~1 million non-traditional properties in UK • Majority built between 1945 the and early 1970s • Over 500 systems built between 1919 and 1976 • Termed system-built or pre-fabricated • Four broad categories, by wall construction • Thermal efficiency varies significantly • In practice, the majority of investment was designed to overcome defects

5. Aims of study • Investigate how many non-traditionally constructed homes still exist in the UK • Identify the risk of fuel poverty within them • Identify examples of best practice and potential case study areas

6. Methodology • Produce estimates of SAP and fuel poverty from all four national HCSfor 80 proprietary systems • Analysis by nation, sub-category, and where possible proprietary system • Results for Scotland and Wales are limited by the design and in the case of Wales by the quality of their HCS

7. Methodology (cont.) • Estimates of NTH for each local authority • Compilation of database from a range of sources • Identified 52 authorities with high levels of NTH • Contacted the management body to establish works undertaken, and the associated changes in SAP or risk of FP

8. Sample results Wall construction in England

9. Non-masonry homes(x1000)

10. SAP ratings by construction

11. LA survey • 19 out of 52 authorities contacted responded • 18 respondents (95%) provided numbers of non-traditional houses (LA or LSVT) • 14 supplied details of the improvements made • 11 provided indicative figures for average work costs • Only 6 had estimates for changes in SAP ratings, • None commented on the effects of improvements on fuel poverty

12. LA Survey • Significant levels of improvement works have been carried out on all non-traditional stock • Typical measures include; EWI or replacement brick cavity walls, LI, central heating and new kitchens and bathrooms • Majority of investment between 1980s and 90s, but there is a significant amount of ongoing maintenance and improvement • Estimated cost of works varies significantly, i.e. from £3,000 to £80,000

13. LA survey • Cost of improvements and the value of property is a factor in an authority’s decision to improve them i.e. Rugby Borough Council • A comprehensive package of measures is required to a target SAP rating of 65 or above • An average cost of £10,000 provides a good indication of expenditure required per property* • Costs can be significantly higher when structural work is required to improve or replace walls

14. Study of heat pumps for Hard-to-treat homes Nicholas Doyle, Places for people Alan Pither

15. Aims • Report on application of heat pumps to hard-to-treat homes • Guidance to local authorities, architects and developers

16. Outputs • Main heat pump technologies • Commercial providers • Applicability of the technology • Case studies • Application matrix • Initial guidance

17. Methodology • Literature review • Database • Interviews with key people • Questionnaire 1: Companies • Questionnaire 2: Utilities • Questionnaire 3: Users

18. Database • UK Heat Pump Network • Heat Pump Association • Ground Source Heat Pump Club • Clear Skies • Now most up to date Dbase

19. Key interviews • Heat Pump Association • Manufacturers, Installers and Suppliers • Energy Companies • Landlords • Ground Source Heat Pump Club

20. Findings • Supplier and installer • Member of HPN • Majority of Technology is G2W plus W2W • Operates throughout UK and occasionally outside • Market split evenly between HA, LA and individual householders • Majority of work in newbuild • Definitely doesn’t believe that HP can be used in HTT - one exception

21. Findings • Cautious • Overloaded with research • Industry changing fast • A tipping point?

22. Utilities survey • All EEC managers called • Only 2 responses • Cautious – commercially sensitive • Special tariffs not perceived as necessary • Funding under EEC 2?

23. Residents’ survey • Prize Draw • Technology ‘Blind’ • Perception of heating and hot water • Penwith HA, Westlea HA, SCHRI • Not Clear Skies

24. Residents’ survey • Majority had positive views with notable exceptions • Controls understood • Split between those who thought they were clear and those who thought ‘could be clearer’ • Costs • Limited time with systems • Average per week - £13 but ranged from £9 -£20 • Majority thought very reasonable or affordable

25. Types of heat pump • Ground to water • Ground to air • Water to water • Water to air • Air to water • Air to air

26. Types of operation

27. Types of system • Ground (or water) source heat pump systems using closed loop water source heat pumps. • Ground (or water) source heat pump systems using open loop water source heat pumps. • Ground source heat pump systems using DX heat pumps. • Air source heat pump systems

28. Case studies 1 Penwith Housing Association, Ludgvan 2 Westlea Housing Association, Withy Close 3 Fife Special Housing Association, Ochil View, 4 Shettleston Housing Association, Glenalmond Street, Shettleston 5 Geothermal Heating and Cooling, Burton On Trent 6 Geothermal Heating and Cooling, Kidderminster 7 West Lothian Council

29. Key lessons • Costs dependent on local geological/site conditions • Ground water levels • Need for lining of boreholes • Bore both supply and return boreholes at the same time and an early stage in the project to monitor flows • Lack of a user manual

30. Key lessons • Need to explain to occupants that their radiators will not be hot to touch • Correct programming and setting of heat pump temperatures to ensure efficient running of the system is vital • Ensure that the best electricity tariff is used • Need to train maintenance contractors

31. The solution for hard-to-treat homes? • High specific heat loss (> 100 W/m2) so require relatively large heating systems. • If the CoP is >3, they will provide cheaper fuel running costs than any other type of heating system (at current tariff levels). • The issue is whether the capital cost is cost-effective compared to the alternatives: • The capital cost of ground source heat pump systems is relatively proportional to the output required.

32. The solution? • Running costs of heat pumps may be lower but not low enough for as an alternative to improved insulation. • Low maintenance costs: £120-£250 per year saving (compared with gas systems?)

33. Factors • Access to mains gas. • Whether the property can be reasonably well insulated using cost effective insulation measures such as cavity wall insulation and loft insulation. • Whether the property is to be comprehensively refurbished, including internal or external wall insulation and floor replacement.

34. Factors • The existing heating system in the property. • Sufficient space for the installation and adequate means of access for the installation equipment. • Other local factors that could affect the cost, e.g. ground water levels, the capacity of the local electricity network.

35. The Matrix

36. Conclusions • Newbuild is the natural market • A significant industry is developing • Existing housing will require individual assessment • Not an alternative to insulation for HTT, but complementary to it

37. Conclusions - suitability? • Ground source heat pumps for insulated houses off mains gas • Air source heat pumps for high rise/mid rise flats • Combination with small-scale renewables, e.g. wind/PV, but even higher capital costs

38. Insulating solid walls: a challenge for local authorities and housing associations Dave Barton, Impetus Alastair Brooks, Impetus

39. Solid wall insulation research Aims: • To produce impartial, practical and user-friendly reports • To help policy community, local authorities and housing associations

40. Objectives To investigate: • experience of specifying, installation and ‘usage’; • range of costs and • perceived performance of the technology.

41. Cost-effectiveness

42. Why solid wall insulation? • More cost-effective than some measures currently promoted • Significant energy savings • A body of experience in social housing • Sound technical guidance • Need to disseminate existing practice and instil confidence

43. Methodology • Desktop research • Telephone interviews with key players • Focus group of experience in: • social housing and • promoting to the private sector • Identify case studies • Householders’ feedback

44. General findings • Building improvement measure, not purely thermal improvements, particularly for EWI • Opportunity measure, needs long-term planning: not simple retrofit • Considerable associated costs and disruption • Technical detailing and quality installations are essential

45. Comparison of IWI and EWI • More experience on EWI • EWI adds value • EWI extends building life • EWI better able to deal with cold bridging • EWI: systems approach, installers and warranty • Overall comparison table in report

46. Costs • Variable dependent upon building type, numbers etc • £2000 for IWI is not unusual • Typically EWI £5000 to £10000 for EWI • Up to £25,000 for a new brick skin and cavity wall

47. Findings: social housing • Generally good feedback from tenants on EWI • Issues with mixed tenure on blocks • Integrate EWI with glazing programme • IWI dependent upon skilled builders • Some concern about robustness of dry-lining in social housing • No detailed research found on householders feedback

48. Findings:private sector • A few small-scale schemes • Limited take-up • Grants of £1000 to £3000, some interest free loans • Usually marketed with other measures

49. Social housing exemplars • Mid-Suffolk District council: post-1919 terrace improvements • London Borough of Enfield: improvements to high-rise blocks • Sandwell Borough Council: an example of a new brick skin and cavity wall • Sheffield City Council: non-traditional low-rise housing

50. Private housing scheme exemplars • Leicester City Council: Realise • The Oxford Solar Initiative • Stroud District Council’s Energy Efficiency Grants • Wyre Borough Council: Wyred for Energy