Publication - Research publication

Developing an Energy Efficiency Standard for Social Housing: consulation analysis

Published: 27 Feb 2013
Directorate:
Housing and Social Justice Directorate
Part of:
Housing, Research
ISBN:
9781782564003

The report summarises the responses to the consultation on the proposed shape and content of an Energy Efficiency Standard for Social Housing (EESSH) in Scotland.

86 page PDF

994.2 kB

86 page PDF

994.2 kB

Contents
Developing an Energy Efficiency Standard for Social Housing: consulation analysis
Annex C: Extracts from Developing an Energy Efficiency Standard for social housing

86 page PDF

994.2 kB

Annex C: Extracts from Developing an Energy Efficiency Standard for social housing

Extract C1

Dwelling types and modelled case studies

5.5 Through examination of the Scottish House Condition Survey ( SHCS), the most common house types in Scottish social housing were identified, listed below . This allowed case studies to be developed based on these house types by modelling the impact of different energy efficiency improvements, as well as the likely cost of installation. Copies of the case studies are available on the Scottish Government website at: http://www.scotland.gov.uk/Topics/Built-Environment/Housing/sustainable/standard.

1. Pre 1919 solid wall flat - ground floor
2. Pre 1919 solid wall flat - mid-floor
3. Pre 1919 solid wall flat - top floor
4. Interwar cavity flat - mid-floor
5. Interwar cavity house - mid-terrace
6. Interwar cavity house - semi-detached
7. Four in a block - lower
8. Four in a block - upper
9. Post war 1950-64 - mid-floor
10. Post war 1950-64 - mid-terrace
11. Post war 1950-64 - semi-detached
12. 1976-83 - mid-floor
13. 1976-83 - mid-terrace
14. 1976-83 - semi-detached
15. 1984-91 - mid-floor
16. 1984-91 - mid-terrace
17. 1984-91 - semi-detached
18. 1992-98 - mid-floor
19. 1992-98 - mid-terrace
20. 1992-98 - semi-detached
21. 2003-07 - mid-floor
22. 2003-07 - mid-terrace
23. 2003-07 - semi-detached

5.6 Whilst it was considered informative to repeat such modelling on a wide variety of house types, there was also the risk that too many case studies would lead to confusion and make it harder for landlords to identify which case studies were relevant to their stock. The list above is thought to provide an indicative range of the most common dwelling types so that social landlords can gauge their stock as they work towards achieving the standard.

Extract C2 The proposed energy efficiency standard

6.1 Proposed energy efficiency standard. Using the modelling work and through consultation with our working groups the proposed energy efficiency standard for social rented housing is to establish a minimum EPC Rating (which we propose should be the Environmental Impact score) which every social rented dwelling will be required to meet by 2020. The standard will be different for different dwelling types. This would enable the Scottish Government to measure reductions in emissions from the 1990 baseline.

6.2 Both the Environmental Impact ( EI) and the Energy Efficiency ( EE) ratings are generated as part of the EPC process. The proposed standard is based on the Environmental Impact rating ( i.e. carbon dioxide emissions) which is generated as part of the EPC assessment. It is proposed that a minimum Environmental Impact rating would be established for broad categories of similar house types based on the modelling. For example, a top floor flat on the gas grid would be expected to achieve an EI rating of "X", whereas a mid-terraced house heated by electricity would be expected to achieve a rating of "Y".

6.3 In most scenarios both scores are improved in tandem, therefore achieving a higher EI rating should lead to a more energy efficient home. However as the EE rating is based on the cost of fuel, in a minority of cases where high emissions reductions can be achieved, the cost of the fuel is actually higher. This could be the case for technologies such as biomass.

6.4 Therefore to act as a safeguard, it is proposed that should a minimum Environmental Impact ( EI) rating be used for the energy efficiency standard, the dwelling's current energy efficiency rating should not decrease as measures are installed.

Benefits of the proposed energy efficiency standard

6.5 As described above, we have drafted detailed case studies modelling the impact of a range of measures, providing assessment of appropriate improvements to the energy performance of that dwelling type. Landlords would have flexibility to assess their stock and implement energy improvements that they consider are most appropriate, which are not necessarily the same improvements identified in the case studies, in order to meet the required EI rating identified for that dwelling type. Depending on the case study type, the efficiency of services and the fuel type, the indicated emissions reduction will vary, taking account of these variables.

6.6 A summary of the key aspects of the proposed standard is set out below:

  • It's fair in that all landlords will be expected to make an equivalent contribution, relevant to their stock.
  • It would allow the Scottish Government to measure reduction in emissions since 1990.
  • Landlords will have full flexibility in the measures they install.
  • As the target will be a minimum EPC rating, landlords can take into account any improvements that have already been made.
  • All tenants would benefit from a minimum level of energy efficiency.
  • The information required is generated when an EPC is produced.
  • It only considers space and water heating and lighting, so concentrates on areas where landlords can make a difference.
  • Landlords would need to have a good understanding of their stock, though some may have been working towards a 100% survey of their stock as part of the SHQS.

Extract C3 Proposed ratings

6.7 The tables below set out the proposed scores to be met by the main dwelling types:

Standard for gas heated homes for 2020

Broad Type Minimum EPC ( EI) rating for the standard Minimum EPC (energy efficiency) rating
Top floor flats heated by gas C (70) C (75)
Mid floor flat heated by gas C (80) C (80)
Ground floor flat heated by gas D (65) C (70)
Mid-terraced house heated by gas C (70) C (75)
End terrace / Semi-detached heated by gas D (65) C (70)
Four in a block - Lower heated by gas D (60) D (65)
Four in a block - Upper -heated by gas D (60) D (65)
Detached / bungalow heated by gas D (55) D (60)

Standard for electrically heated homes for 2020

Broad Type Minimum EPC ( EI) rating for the standard Minimum EPC (energy efficiency) rating
Top floor flats heated by electricity D (60) D (65)
Mid floor flat heated by electricity C (70) C (70)
Ground floor flat heated by electricity E (50) D (60)
Mid-terraced house heated by electricity D (55) D (60)
End terrace / Semi-detached heated by electricity E (50) D (60)
Four in a block - Lower heated by electricity E (50) D (60)
Four in a block - Upper -heated by electricity D (55) D (60)
Detached / bungalow heated by electricity E (50) D (55)

NB It is proposed that the energy efficiency standard is based on the EI rating. The Energy Efficiency rating is also included in the tables above to give an idea of what a standard based on that rating may look like and to help inform responses to the consultation.

Extract C4 Treating unusual dwelling types

6.14 As the case studies are designed to cover the main dwelling types, it is envisaged that there would be no requirement for any exceptions in the new standard. However, as noted above the modelling work and case studies don't cover all social rented housing; there are some more unusual types of dwelling in the sector. Even within common house types there are individual dwellings where circumstances differ. The ongoing peer review process is considering how best to handle the approximately 10% of the stock which isn't covered by the work done to date. However, one suggestion is that a methodology is set out for landlords to follow. This would require them to use the 1990 base assumptions to record a baseline for their individual dwelling and calculate a set percentage reduction to identify a required improvement. This method could be used for all unusual dwelling types, including types where the 1990 baseline is significantly below the generic baseline for a similar dwelling type. The percentage reduction would be set by Scottish Government to recognise the different dwelling circumstances and be in line with the burden on other dwelling types. This is set out in more detail below.

Example of the proposed methodology for dealing with Hard-to-Treats.

Example: no-fines concrete, semi-detached, gas heated dwelling, constructed in 1978.

1. The landlord enters survey details from the individual property into RdSAP using the same assumptions for the building services elements as for the generic dwelling type (as discussed in 4.20). The relevant generic building type for this example will be 1976-1983 built gas heated semi-detached house.

2. The landlord calculates the baseline Environmental Impact rating. For this example dwelling the baseline EI rating is F (28) with approximate CO2 emissions of 103 kg/m2/year. This is lower than the generic building type which is E rated.

3. The Scottish Government will set the required percentage reduction and the landlord will calculate what the reduction in emissions should be for that individual dwelling. For example, the dwelling must achieve a minimum 42% reduction in CO2 emissions, reducing the emissions to approximately 60 kg/m2/year.

4. The landlord considers the range of appropriate cost effective options by which the dwelling can meet the required reduction in energy and emissions. These are likely to include:

  • 100% low energy lighting;
  • A condensing boiler;
  • Time and temperature zone controls;
  • Roof insulation; and
  • Double glazing.

5. The landlord chooses the best combination of measures and undertakes the required work

6.15 This approach will only be permissible for certain house types and certain circumstances, which will be defined in the final version of the standard.


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