Heat and Energy Efficiency Technical Suitability Assessment: consultation analysis

Executive Summary

Summary

Respondents agreed that the Scottish Government should develop a Heat & Energy Efficiency Technical Suitability Assessment (HEETSA) framework for the retrofit of buildings. Examples of when a HEETSA should be required included for specific situations, such as retrofit works linked to public funding, or for retrofit works that are more complex and/or have greater risk, such as works to traditional buildings. The HEETSA should build on existing assessment and investigative methodologies and improve on any shortcomings rather than invent something new. Concerns were raised of insufficient skills such as for assessing traditional buildings. However, it was felt that this could largely be addressed by additional training which may only be needed if a HEETSA assessor chooses to assess more complex buildings. Respondents supported a regulated delivery model which, in particular, ensures that the HEETSA assessor is independent of the outcome of the assessment. Respondents recommended that the HEETSA should produce a standardised output for the building owner and that the data gathered forms part of a building logbook.”

Introduction

In June 2025, the Scottish Government launched a consultation that sought views on the scope of a Heat & Energy Efficiency Technical Suitability Assessment (HEETSA) for the retrofit of buildings. The aim is to safeguard consumers by developing a technical suitability assessment which ensures that building owners can understand which retrofit measures are appropriate when improving their energy efficiency and changing their heating system.

This report presents the key findings from the consultation.

Respondent Profile

There were 88 responses to the consultation. Overall, 70 responses were received from organisations, and 18 responses were from individuals. The highest number of organisation responses were received from national representatives or trade bodies (n=18), followed by local authorities and public bodies (n=16). A full breakdown of organisation sectors is provided in Figure 1.

Key Findings

The consultation comprised 13 questions. The key findings have been integrated into six groups of questions below.

Value and Purpose of a HEETSA

Question 1 asked whether it would be valuable for the Scottish Government to develop a HEETSA. Respondents were generally supportive of the development of a HEETSA (79%). Key reasons for this support included:

• Quality and accountability in retrofit advice: A HEETSA should ensure skilled, qualified, and impartial assessors. It will improve trust and accountability in retrofit advice.
• Standardised and holistic assessment approach:  It should deliver a consistent assessment approach which covers the wide range of building types (including complex buildings) and building technologies.
• Empower consumers through better advice: It should provide better quality and more tailored advice to building owners. It enables them to make decisions suited to their circumstances.
• Support public policy and resource efficiency: A HEETSA should support the national strategy to decarbonise homes and address fuel poverty. It also enables a better allocation of public resources.
• Upskill and grow retrofit workforce: It should help to upskill and grow the retrofit market.

It was noted that the HEETSA should be affordable. There was also some concern whether the scheme could be delivered and the workforce ready by the proposed start date of 2027.

The responses to Question 12 highlighted a wide range of circumstances where a HEETSA should be required.

• Specific situations: The most common suggested triggers for a HEETSA were either to access public funding for retrofit or to demonstrate regulatory compliance/justify exemption, in particular linked to the upcoming PRS MEES. Others suggested that it should be linked to the existing planning permission or building warrant process, or when buying or selling a property.
• Specific building types: It was also recommended that a HEETSA should be required for retrofit works for specific building types. Suggested building types included hard-to-treat, historic, traditional or listed buildings, and communal or tenement buildings.
• Specific building works: There were also suggestions that the requirement for a HEETSA should depend on the type of retrofit works. In particular, before installation of a low carbon heating system or when significant refurbishment of a building takes place.

Scope and Methodology of a HEETSA

Question 2 explored what part of the retrofit process the HEETSA should cover. Respondents could select multiple parts of the process. Most respondents to this question recommended that HEETSA should cover retrofit assessment (78%). Additionally, respondents thought that HEETSA should cover retrofit design (66%), occupancy related factors (60%) and retrofit specification (50%). Some respondents felt that HEETSA should cover all of the retrofit lifecycle stages whilst a similar number suggested that HEETSA should focus on the assessment phase only.

Question 4 requested details of existing assessment methodologies that could be used for HEETSA, and to identify any gaps where adapted or new methodologies are needed. A diverse set of existing tools and standards were recommended to assess different aspects of retrofit. Many of the suggested gaps focussed on existing methodologies that should be more commonly used e.g. the greater use of performance verification, such as pre and post installation monitoring, to better assess the effectiveness of installed measures. Other suggested gaps tended to focus on improving existing methodologies and associated guidance, rather than developing new ones. For example, setting out evaluation methods suitable for traditional and hard-to-treat buildings such as tenement buildings. Additionally, the need for better guidance to assess the choice of clean heating system within the specific building context.

Question 5 investigated the best approach to address those gaps in methodologies identified in Question 4. Aligned with the feedback from Question 4, responses called for HEETSA to build generally on existing processes and methodologies rather than reinvent them. In general, it was suggested that the Scottish Government should lead and fund any further development of methodologies. Gaps should be identified through consultation. Any improved or new methodology should be delivered by industry and/or academic providers. This should help ensure that the methodologies are robust, practical, and align with existing professional standards. The Scottish Government should collaborate throughout with professional bodies and those delivering or researching retrofit.

Delivery & Accreditation

Question 3 asked for views on the HEETSA delivery model. Most respondents (78%) supported some form of regulated structure in which HEETSA assessments are undertaken. The majority recommended that the Scottish Government should accredit organisations who in turn accredit HEETSA assessors. Many identified particular existing professional bodies that were well placed to become accrediting organisations for HEETSA.

Question 9 explored whether the HEETSA assessor should be independent of the outcome of the assessment. For example, that they should not financially gain from the uptake of any measure identified in the HEETSA. The majority of respondents that answered this question agreed that the HEETSA assessor should be independent (86%). This is primarily to ensure that the assessment is carried out in a robust and unbiased manner. This builds consumer trust in the process and protects the consumer from the installation of unsuitable retrofit measures.

Skills & Capacity

Question 6 was an open question for views on the skills and qualifications required to undertake a HEETSA. Responses recognised that there is an existing pool of potential HEETSA assessors. They possess relevant skills and experience, which can be built upon. A wide range of suggestions were provided of existing professional qualifications and training courses that could be required of an assessor. Concerns were raised regarding the specialist knowledge needed regarding, for example, traditional buildings and emerging new technologies. On balance, it was felt these could largely be addressed by top up training.

The skill set required to deliver a HEETSA depends on the building type/situation requiring assessment. Hence, a modular approach could be adopted where the necessary upskilling depends on the building being assessed. This means that many construction industry professionals would be able to deliver HEETSA once it is codified and they received any additional training necessary in those HEETSA specific process requirements that might be required for them. There was little appetite for the creation of an entirely new qualification, or discipline, to deliver HEETSA.

Question 7 explored whether it was feasible for an individual assessor to have the skills and knowledge to complete a HEETSA on their own. The alternative was for a HEETSA to be completed by multiple specialists. There was no clear view, with a similar number of respondents favouring each of the two options. A single assessor was preferred due to reduced cost and being more time-efficient than involving and co-ordinating multiple specialists. Multiple specialists were preferred due to the breadth and complexity of building retrofit. Some noted that the decision of whether an individual assessor is appropriate would depend on the complexity of the building or project.

Data & Integration

Most respondents to Question 8 (82%) agreed that non-personal data gathered through a HEETSA should be stored to form part of a ‘building logbook’ or ‘green building passport’. A wide range of reasons were given for this view:

• Live accessible logbook: Enable a live, accessible logbook with trusted data sources.
• Better support owners and tenants: Inform and better support current and future tenants/owners, in areas such as improving the understanding of their home and encouraging maintenance.
• Improve consumer confidence: Improve transparency and consumer confidence in the assessment and recommendations for a property.
• Improve data quality: Support data quality for validation as well as compliance e.g. associated with relevant standards.
• Assist Government initiatives: Assist existing and future government policies, central interventions, and funding streams.
• Improve assessment management: Help enable improved asset management.
• Reduce duplication: Reduce duplication associated with re-collecting the data and improve cost and time-effectiveness.

A few respondents opposing the storage of non-personal data cited a risk of the data becoming outdated. A few respondents also believed the data was either unlikely to be re-used or consumers may opt out from storing their data. There were also concerns around consumer protection associated with data storage.

Most respondents to Question 11 (84%) agreed that the HEETSA should result in a standardised certificate or report. The key benefits highlighted included the consistency of assessments and data collected, and the comparability of information between properties. It was considered to aid the government e.g. provide details of suitable retrofit measures for government funding schemes. It was also considered to aid the private sector e.g. provide market intelligence on those measures deemed technically suitable. A concern raised was that a standardised output could limit the ability of a flexible assessment approach to address the wide variation in the housing stock.

The respondents provided recommendations for the content of a HEETSA report or certificate. The most common suggestions were as follows:

• Technical: Technical findings, both of measures and any risks and mitigations e.g. related to mould and condensation.
• Suitable measures: Show the benefits of alternative retrofit options to enable informed decision making e.g. based on carbon savings, installation and running costs.
• Property overview data: Provide property details such as current condition, location, context, current systems and past interventions.
• Demonstration of compliance: Show that it meets relevant requirements and standards, such as building regulations, planning requirements, and building services standards. It should also include any verification of performance.

Legal & Regulatory Framework

Most respondents (79%) agreed that it is necessary to develop a legal basis for HEETSA (Question 13). It was suggested that this would ensure that the HEETSA assessor is held accountable for their work, safeguarding the consumer. It should also help ensure the delivery of a consistent and quality service, including enabling monitoring and enforcement of implementation. Its legitimacy should improve market confidence and uptake of HEETSA. A legal framework is also expected to be needed to integrate with other regulations, such as PRS MEES. The main reasons for opposing were the time, resource and cost demand of developing a legal basis. Some suggested a flexible approach to mitigate this, such as a phased introduction to enable early uptake while a legal basis is developed. There was a general note that care should be taken to avoid overlap and duplication with existing regulations.

Question 10 explored the relationship between the EPC framework and HEETSA. Most respondents (75%) agreed that HEETSA outputs should feed into the EPC in some way. There was similar support for two options. The first that the HEETSA should result in the production of a revised EPC. The alternative was that the HEETSA outputs should be acceptable evidence to override EPC default values, but a revised EPC is not mandated. The most frequently cited reason for both options was that the HEETSA data could improve the accuracy of EPCs. The most common reason in favour of the first option was to ensure consistent information in both the HEETSA and EPC. Support for Option 2 was principally based on the view that EPCs and HEETSA serve distinct purposes, and a clear separation should be maintained.

There were some concerns of linking the EPC and HEETSA. Some respondents were concerned that introducing varying levels of accuracy could undermine the EPC’s role as a consistent, standardised comparative tool. There was also concern that linking HEETSA to EPCs might incentivise HEETSA assessors to prioritise measures that improve EPC ratings, rather than those best suited to the building.