Scottish Energy Performance Certificate (EPC) Accreditation Scheme: operating requirements

Quality assurance

This section sets out the minimum requirements on Approved Organisations to assure the quality of the EPCs being lodged by their members.

4.1 EPC audits

4.1.1 As set out within Regulation 12(3) of the 2025 Regulations, AOs are responsible for:

• “ensuring that members of the scheme carry out consistent and accurate energy assessments in an independent manner”; and
• “ensuring that a specified proportion of energy performance certificates and property reports are audited, including where practicable by means of an on-site inspection, to assess whether they are prepared in a consistent, accurate and independent manner”

4.1.2 AOs must have quality assurance procedures in place to check the quality of EPCs produced by their assessor members and to undertake appropriate corrective action where the required standard is not met.

4.1.3 AOs must ensure that a minimum of 2% of the total number of EPCs produced by their members are checked for accuracy.  

4.1.4 This 2% figure will be kept under review by the Scottish Ministers, with a potential view to moving towards a more risk-based auditing approach. However, this will be dependent on evidence received by AOs.

4.1.5 As a minimum, AOs must ensure that output from any active EPC assessor is checked at least every 6 months. Where the number of EPCs produced by an individual assessor is 5 or less within a 6 month period, the audit period may be extended to 12 months.

4.1.6 EPCs selected for audit should be based upon a random sample, augmented by any identified need for targeted audit as a result of:

• smart audit failures – expanded on below
• new membership audits – all new EPC assessor members must have their output checked within the first month of active membership
• follow-on audits – it is expected that any EPC produced, following a failed audit, will again be subject to an audit when re-lodged
• poor performance – it is expected that any assessor who persistently fails audits, or is regularly close to failing audits, will be subject to targeted auditing
• complaints; and
• requests from the Scottish Ministers or other organisations identified by the Scottish Ministers

4.1.7 AOs must provide the Scottish Ministers with information on their audit strategy as part of their application process, and must notify the Scottish Ministers if this changes. The outcomes of these audits must be provided within the quarterly reports provided to the Scottish Ministers.

4.1.8 The Scottish Ministers reserve the right to increase audit frequencies (including increasing the 2% minimum requirement). This may be, for example, where an AO fails in its duty to adhere to the requirements set out in their letter of approval.

4.1.9 AOs must also comply with any requests from the Scottish Ministers for further information around audit failures, and future onsite auditing visits either by the Scottish Ministers or any third party appointed on their behalf.

4.2 Smart audits

4.2.1 A smart audit is a ‘risk based’ audit based on pre-defined set of criteria. Prior to the in-force date of the remainder of the 2025 Regulations, the Scottish Ministers will define, with input from the newly appointed AOs, smart auditing criteria that must then be implemented by AOs – and this document will be updated to reflect that decision.

4.2.2 While smart audit rules are yet to be established, AOs must have a mechanism in-place – or co-operate with the Scottish Ministers on a regular basis – to identify and investigate high volumes of EPCs lodged by EPC assessor members. Initially, this threshold is >120 lodgements per month – however, the Scottish Ministers reserve the right to modify this threshold.

4.2.3 While not mandated under this Accreditation Scheme, the role of artificial intelligence (AI) in EPC auditing may present opportunities for AOs to improve the efficiency of desktop auditing. However, prior to the introduction of any AI auditing regime, AOs must first notify the Scottish Ministers of their intentions to introduce (or trial) such tools.

4.3 Onsite audits

4.3.1 Onsite audits may either be an accompanied or unaccompanied visits, arranged either by the AO or the Scottish Ministers.

4.3.2 While onsite audits are not mandated for AOs to undertake, the Scottish Ministers remain committed to introducing an independent, onsite audit regime in within 12 months of the remainder of the 2025 Regulations coming into force. This document will be updated to reflect this.

4.4 Audit evidence

4.4.1 EPC assessor members must provide evidence, when requested by their AO, to prove that the EPC lodged, accurately reflects the evidence they have gathered.

4.4.2 All evidence provided (i.e. the assessment data, within the meaning of Regulation 2 of the 2025 Regulations) must be unique to the property being assessed and be reflective of the date of assessment.

4.4.3 The scope of the evidence/assessment data collated must be sufficient to allow an independent auditor to complete an appraisal of the initial assessment.

4.4.4 It is the responsibility of AOs to provide EPC assessor members with guidance on what can be considered to be appropriate evidence/assessment data.

4.4.5 AOs and assessors must retain assessment data, as well as any audit findings, for a period of 10 years in a secure manner. This information must not be released unless in accordance with the provision contained within Regulation 18 of the 2025 Regulations.

4.5 Audit accuracy

4.5.1 EPCs can fail an audit due to a lack of evidence or due to technical reasons.

4.5.2 Technical reasons are as follows:

• yes/no failure based on whether the correct heating system has been identified
• yes/no failure based on whether the correct building typology has been identified
• yes/no failure based on whether the correct building address or Unique Property Reference Number (UPRN) has been assigned
• yes/no failure based on whether the correct potential improvements have been identified
• yes/no failure based on whether the EPC band has changed; and
• a rating change outwith a +/- 5% tolerance. This is expanded on below for each individual metric.

4.6 Audit failures

4.6.1 EPCs identified as being below standard (including incorrect data entry that impacts the EPC or the Property Report) must be replaced within 6 weeks, and corrective action must be taken where assessor activity is found to be outwith accepted practice.

4.6.2 If the EPC assessor does not have to re-visit the building, and the issue(s) can be rectified remotely, the EPC should be replaced within 1 to 2 weeks.

4.6.3 Responsibility for replacement of defective EPCs rests with the assessor who provided the initial EPC. If the original EPC assessor cannot be contacted, is no longer practicing, or has failed to re-lodge within 6 weeks, then the AO must act to replace the defective EPC. The replacement EPC must be provided within 12 weeks of the original assessor being required to replace the EPC.

4.6.4 The building owner must be notified in all cases where a defective EPC is identified, and provided with a clear explanation on the next steps to be taken (including whether any overall ratings have changed, as a consequence of this).

4.6.5 It is the responsibility of AOs to provide feedback (and, where necessary, support) to EPC assessor members regarding any audit failures, and to take appropriate steps to prevent reoccurrence.

4.6.6 In the event of assessor suspension following an audit failure (or persistent failures), AOs must investigate and take any necessary action in a prompt manner.

4.6.7 All EPC assessor members must be made aware of the audit failure process and any consequences (for example, through any Terms and Conditions of membership).

4.6.8 Where fraud is identified/suspected, AOs must take action as per their Fraud Risk Assessment.

4.7 Approved organisation auditor competency

4.7.1 AOs must ensure that EPC auditors – either employed directly by the AO or via a third party - are competent and qualified to undertake such audits.

4.7.2 As a minimum, EPC auditors must:

• be suitable experienced and qualified, by holding the appropriate qualification(s) and/or APEL certificate for the categories of building(s) they will be auditing;
• undertake appropriate CPD;
• be subject to moderation by fellow auditors or verified by a more senior individual;
• have a strong understanding of the Scottish EPC Accreditation Scheme and relevant legislation; and
• have declared that they will identify and declare any potential conflicts of interest.

4.7.3 Prospective AOs must provide information around how the competency and independence of auditors is maintained as part of their application, including the proposed checks to be carried out on auditors themselves.