Publication - Research and analysis
Domestic and non-domestic energy performance certificates review: executive summary
Analysis of responses to our three public consultations about energy performance certificates (EPCs).
Possible actions
- Calculation
- Assessment
- Reporting
- Database
Domestic Building recommendations
| Possible actions | rationale | time frame | cost | impact | magnitude |
|---|---|---|---|---|---|
| The Scottish Government to arrange for the data gathered through the monitoring of the SEEP Pathfinder projects and HEEPS ABS to be collated and assessed against improving the accuracy of the calculation methodologies. | improving accuracy | medium term | medium | low to medium | medium |
| A systematic research programme to measure in-situ U-values for different existing stone wall types to assess the validity of the current range of U-values within RdSAP; proposed revision to the stone wall U-value calculation algorithms. This research program would probably take at least 2 years to identify and monitor sufficient properties to provide a robust empirical basis to make changes to the existing algorithms. This research programme could assess the impact of the wall condition and water saturation levels on the thermal performance of the walls. | improving accuracy | long term | high cost | high | medium |
| Extending the range of stone wall types would require collating more empirical data in terms of the type of stone and its heat loss performance so that default U-values could be derived and included into the software. This certainly could be part of the above research program. In the interim, a piece of research could collate and calculate default U-values that could be published as a stand-alone booklet (or more likely as an online data reference) that could be referred to by assessors. | improving accuracy | medium term | low cost | medium | medium |
| Adopt thickness related U-values for half-brick thick, and for 1.5 and 2-brick thick walls, amend Appendix S accordingly, and then embed the appropriate defaults into the SAP, RdSAP and SBEM software models. | improving accuracy | medium term | medium to high cost | medium | low |
| Include an assessment of the dwelling's thermal mass into Appendix S of the SAP manual, and within the RdSAP software. | improving accuracy | medium term | medium | high | medium |
| Include shutters within RdSAP as an item to be recorded during the survey. | improving accuracy | medium term | low cost | low | low |
| Use The Guide to Non-traditional Housing in Scotland 1923 -1955[1], and other individual BRE reports on specific non-traditional dwelling types, to calculate theoretical U-values for different non-traditional dwelling types and incorporate them into SAP and RdSAP. | improving accuracy | long term | high cost | high | low |
| Establish a Scottish PCDB reference database to allow for Scottish-based inputs such as fuel costs and improvement costs, to calculate the EPC outputs on the EPC such as the savings on fuel costs, and the paybacks. | improving accuracy | long term | high cost | high | high |
| Amend RdSAP procedures and software to differentiate between CFLs and LED with regard to assessing lighting energy consumption, and potential savings. | improving accuracy | medium term | medium | low | medium to high |
| Allow the inclusion of in-situ test results such as air pressure testing or U-value measurements to be included into the RdSAP assessment of existing properties. Such procedures are already defined in SAP for dwellings. | improving accuracy | medium term | medium | high | high |
| The impact of the changing fuel prices on the SAP rating over time is accounted for in quite a blunt way within SAP and RdSAP. Rather than use an overall average fuel price index, a fuel price index for each fuel should be calculated and embedded with the SAP and RdSAP calculations. Going forward we can no longer have the confidence that all fuel costs will follow a similar trend or direction. | improving accuracy | long term | high cost | high | high |
| Review the financial benefit of embedded generation within the EPC process. Currently the SAP score on the EPC is improved with electricity generating renewables; however, it is not clear how this translates to an energy cost saving for the occupant. | improving accuracy | long term | high cost | high | low to medium |
| Develop a Scottish PCDB which all approved software would use when generating Scottish EPCs. This would have data on energy efficiency improvements and fuel prices which reflect the Scottish market. | improving accuracy | long term | high cost | high | high |
| Develop more algorithms for default room in the roof shapes | improving accuracy | long term | high cost | medium | medium |
| Redefine half-wall type dwellings in RdSAP. | improving accuracy | long term | high cost | medium | medium |
| Incorporate the full SAP DH/CHP system data entry items into the RdSAP methodology with appropriate conventions and defaults when the information is not available. | improving accuracy | medium to long term | high cost | high | low |
| Consider possible changes to the SAP and RdSAP methodology with regard to 'penalising' flat rate charging. | improving accuracy | medium term | medium | medium | low |
| Consider possible change to convention on definition of a heated corridor in multi-storey blocks connected to DH/CHP systems where the system risers are in the circulation areas. | improving accuracy | short term | low cost | low to medium | low |
| Allow the actual number of extract fans, air bricks, and flues, and the presence of a draught lobby to be entered within RdSAP programs. | improving accuracy | medium term | medium | medium | high |
| Allow for air infiltration rate test results to be entered into RdSAP. | improving accuracy | medium term | medium | medium | low to medium |
| Change the Appendix T rules so that draughtproofing is included as an improvement recommendation where the level of draughtproofing of the windows and doors is less than 100%. | improving reporting | medium term | medium | low | low |
| Include variations in pre-2003 wood double glazing default U-values to take account of different thicknesses in the glazing gap. | improving accuracy | medium term | medium | low | medium |
| Amend Appendix T so that both a recommendation for secondary glazing and replacement double glazing can appear on the EPC. | improving reporting | medium term | medium | low | medium |
| Incorporate shutters into the RdSAP methodology and into Appendix T. | improving accuracy and reporting | medium term | medium | low | low |
| Publish a convention to accommodate wall insulation that is less than 50mm thick, or falls between the default thicknesses. | improving accuracy | short term | low cost | low to medium | medium |
| 'System built' conjures up negative perceptions, and the term should be switched to 'non-traditional'. System-built describes a particular method of construction; not all non-traditional housing in Scotland is system-built. | improving consistency | short term | low cost | low | low |
| Publish a guide on calculated and tested U-values for non-traditional and 'system built' buildings in Scotland | improving consistency | long term | high cost | high | low |
| Develop procedures and conventions to take account of insulation that cannot be seen. This would include adding an addendum to the data entry take account of insulation and improvements that do not meet the current standard of documentary evidence. | improving accuracy and consistency | medium term | medium | high | medium |
| Develop a household log book akin to the benchmark log book for boilers in which contractors would sign off insulation improvements completed in a dwelling. | improving accuracy and consistency | medium term | medium | high | medium |
| Clarify conventions with regard to using 'system built' as a wall type. This designation should only be used after all non-destructive means have been employed to categorise the wall type as this has a big influence on how measures are automatically generated for wall insulation. | improving consistency | long term | low cost | medium | low |
| Support the development of a wider role for EPC assessors in Scotland through further training and CPD | improving consistency | medium to long term | medium to high cost | medium | high |
| Clarify RdSAP conventions with regard to circumstances under which automatic recommendations can be suppressed. | improving consistency | short term | low cost | low | low |
| Enable and allow assessors to modify the PCDB costs for improvement works, allowing the reporting of capital costs of improvement measures to be made more specific to the community where the works would be carried out. | improving consistency | medium to long term | medium to high cost | medium | high |
| Allow variations in the costs of the works proportionate with the percentage of the property being treated. | improving consistency | medium to long term | medium to high cost | low | low to medium |
| Amend the RdSAP software to allow for the inclusion of Appendix Q calculated savings for technologies not currently incorporated in RdSAP, following the same guidelines that are currently applied to using such procedures in SAP. | improving consistency | medium to long term | high cost | medium | low |
| Explore with SQA and RICS the development of a higher-qualified, broader-skilled, more professional EPC assessor. | improving consistency | long term | medium to high cost | medium | high |
| Undertake a research exercise to determine how many EPCs issued under RdSAP 2012 v9.92 breached the 'smart audit rules'. | improving consistency | short term | medium | high | high |
| Introduce 'smart auditing' as part of the Protocol Organisations' quality assurance targets in Scotland. | improving consistency | short term | low cost | high | high |
| Introduce the requirement that the quality assurance procedures include independent on-site re-inspections. | improving consistency | medium term | high cost | high | high |
| Establish an independent regulator (or vest it within Scottish Government) to oversee the independent re-inspection of EPC assessments, and to report annually on the results. | improving consistency | medium term | high cost | high | high |
| The Scottish Government in conjunction with SQA to identify and introduce Scottish qualifications, based on National Occupational Standards, for EPC assessors, for existing dwellings, new build dwellings, and non-domestic dwellings. Part of this qualification would be the potential assessor successfully completing a national examination. | improving consistency | medium term | high cost | high | high |
| All SAP, RdSAP and SBEM training courses being offered in Scotland, and the respective trainers, should be vetted with regard to their competence and the experience of the trainers. These items should not be left in the hands of the accreditation Schemes. | improving consistency | medium term | medium | high | high |
| The Scottish Government to agree with the Accreditation Schemes rules and procedures for suspending and de-registering assessors or companies that bring the EPC scheme into disrepute by misrepresenting data. | improving consistency | medium term | medium | high | high |
| The convention on rooms in the roof should be re-written to provide clear, unambiguous and definitive guidance on when detailed room in the roof measurements are required. | improving consistency | medium term | medium | medium | low |
| Develop procedures to take account of insulation that cannot be seen. This would include adding an addendum to the data entry that the U-values take account of insulation that has not been accompanied by the current standard of documentary evidence. | improving consistency | medium term | medium | medium | low |
| Develop a household log book akin to the benchmark log book for boilers in which contractors would sign off insulation improvements completed in a dwelling. | improving consistency | medium term | medium | high | high |
| Require a full SAP assessment when a dwelling is connected to a DH/CHP system. | improving accuracy | medium to long term | high cost | high | low |
| Define a convention on when to make the recommendation to connect to a local DH/CHP system. | improving consistency | short term | low cost | high | low |
| The Scottish Government could mandate that Display Energy Certificate-type certificates be displayed outside the door on boiler plant setting out the DH/CHP operational efficiencies. This would provide an accessible source of data to the assessor. | improving accuracy | medium term | low cost | high | low |
| The Scottish Government should encourage DH/CHP system owners to get the operational parameters of their systems added to the PCDB database. | improving accuracy | medium term | low cost | high | low |
| Define a convention in RdSAP for assessing air bricks. | improving consistency | medium term | medium | low | high |
| To support the inclusion of air infiltration rate test results, define a convention within RdSAP governing the necessary standards to be met by the tests, the qualifications of those carrying out the tests, and the requisite documentation to support this development. | improving accuracy and consistency | medium term | medium | medium | medium |
| Change the convention to require RdSAP assessors to measure individual windows in Scotland. | improving accuracy and consistency | short term | low cost | medium | high |
| Identify appropriate wall insulation techniques for different non-traditional dwelling types so that the EPC will potentially recommend insulating the walls. | improving reporting | medium term | medium | high | low |
| Incorporate shutters into Appendix T so that they may appear as a possible improvement. | improving reporting | medium term | medium | low | low |
| In order to avoid significant material changes to the EPC as required for EPBD, consideration should be given to a separate associated energy efficiency advice report or improvements report. This report would be both methodologically and administratively linked to the EPC itself. | improving reporting | long term | high cost | high | high |
| The format of the EPC in Scotland should reflect on the potential for assistance through Scottish Government schemes and/or the Energy Companies Obligation. Assessors are currently required to identify the tenure of the properties being assessed and many of the schemes for assistance are targeted at specific tenures. Messages around whether the property does or does not meet a sectoral EPC band target could be provided on the EPC. | improving reporting | long term | high cost | high | high |
| In order to avoid significant material changes to the EPC as required for EPBD, consideration should be given to a separate associated energy efficiency advice report or improvements report. This report would be both methodologically and administratively linked to the EPC itself. | improving reporting | long term | high cost | high | high |
| Use the EPC data to provide tailored advice and support to householders by developing a parallel reporting process. | improving reporting | long term | high cost | high | high |
| A consumer review of the EPC format is needed in order to revise the way that information is presented on the document so that it is understandable by the householder, and not just a technical audience. The review should consider information such the values and terms used and what these mean to the consumer. The certificate itself is an authorised legal document; however, the information contained within certain sections is indicative and not an approved schedule of planned works. | improving reporting | long term | high cost | high | high |
| Amend the wording on the EPC with regard to recommendations for specific construction types, that more additional expertise is needed. This could be done achieved through the assessor selecting an addendum item for the need for professional expertise with specific construction types. | improving reporting | long term | high cost | high | high |
| Amend the wording on the EPC with regard to recommendations where the building is obviously not wind and weather tight that additional work may be required for the benefits of any improvement works are to be realised. This could be done achieved through the assessor selecting an addendum item for the need for professional expertise with specific construction types. | improving reporting | long term | high cost | high | high |
| Develop differential SAP targets for dwellings for different primary heating fuels. | improving reporting | long term | high cost | high | high |
| Where the rating is subject to the type of metering (e.g. with electric storage heating) or the presence of low energy lighting, a note should be added to the EPC stating that switching tariffs or replacing the low energy lighting with less efficient lighting may have a negative impact on the rating to landlords and owners on the actions that can have an adverse impact on the SAP rating. | improving reporting | short to medium | low cost | low to medium | low to medium |
| Adjust the presentation of fuel costs and savings to reflect annual fuel bills (not 3-year totals) and annual savings. There may also be some benefit of also including what the annual total converts to in terms of an average weekly fuel bill in summer and winter, to better inform householders. | improving reporting | medium term | medium | low | high |
| Consider the value that can be added to the EPC process with a separate occupant report. This kind of approach could help to address the view that the EPC in itself should not fundamentally change; the data used to generate it could add significant value to a supplementary advice report which then brings into play specific occupant factors. | improving reporting | long term | high cost | high | high |
| Adjust the wording on the domestic EPC so that it refers to carbon dioxide equivalent (or CO2e) emissions rather than simply carbon dioxide. | improving reporting | short term | low cost | low | high |
| All data referenced from the PCDB to produce the various metrics on an EPC should be declared on the lodged document. | improving reporting | long term | medium | low | high |
| Use the EPC data to provide tailored advice and support to householders by developing a parallel reporting process. | improving reporting | long term | high cost | high | high |
| Include connecting to DH/CHP system within Appendix T. | improving reporting | medium term | medium | high | low |
| Require the summary data report to be lodged on the national register alongside the EPC, and to make this summary report available online alongside the EPC. | improving reporting | medium term | high cost | medium | high |
| Develop a database alongside the EPC register to upload PAS20/30 certificates of compliance that can be accessed by householders and assessors to check if insulation has been installed. | improving consistency | medium term | high cost | medium | medium |
Non-domestic Building recommendations
| Possible actions | rationale | time frame | cost | impact | magnitude |
|---|---|---|---|---|---|
| Contact BRE/UK Government department to determine whether there are any plans to increase the range of new technologies catered for in SBEM. | improving accuracy | medium term | medium | high | medium |
| Amend the EPC generator module to allow input of operational energy data such as used in DECs in other parts of the UK. | improving accuracy | medium term | medium | medium | medium |
| Require more detailed energy audits as the basis for funding decisions. | improving accuracy | short term | low cost | low to medium | medium |
| Include operational ratings on EPCs in addition to asset rating. Include more comparators (e.g. typical figures for building stock, or at least the building archetype). | improving reporting and recommendations | medium term | medium | low to medium | high |
| Publish operational as well as asset information on EPCs. | improving reporting and recommendations | medium term | low to medium cost | low to medium | medium |
| EPCs should not be used as the basis for works specifications or costs without further more detailed assessment. | improving reporting and recommendations | short term | low cost | medium | medium |
| Produce and publish a database of EPCs and operational energy consumption for public buildings in Scotland | improving accuracy | medium term | medium | low to medium | high |
Contact
Email: Steven.Scott@gov.scot
There is a problem
Thanks for your feedback