Home Decarbonisation Skills Training competition: summary of evaluation findings and policy response
Published 1 September 2025
Applies to England
© Crown copyright 2025
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1. Introduction
To help grow the retrofit supply chain, the Department for Energy Security and Net Zero (DESNZ) launched the Home Decarbonisation Skills Training Competition (HDSTC) Phases 1 & 2 to increase the number of trained installers and retrofit professionals in England to help meet Net Zero targets.
Managed by the Midlands Net Zero Hub (MNZH), Phase 1 of the competition awarded £9.2 million in grant funding to 18 training providers to deliver accredited training across England between 2022 and 2023. Following the success of this first phase, DESNZ allocated an additional £8.85 million to support 24 training providers in Phase 2, which concluded in August 2024.
To assess the impact of the scheme, in August 2023 MNZH commissioned Winning Moves to conduct an independent evaluation of the scheme. Delivered in two stages to align with the rollout of the HDSTC, the Phase 1 evaluation report focussed on scheme implementation, trainee outcomes and value for money. The Phase 2 evaluation report expanded on this by exploring longer-term trainee outcomes and tracking progress among Phase 1 trainees.
This publication summarises the key findings from both reports and highlights how DESNZ used the insights to inform and improve subsequent policy development.
2. Home Decarbonisation Skills Training Competition Phase 1
HDSTC 1 was launched in September 2022. 18 UK training organisations received funding to deliver training under three work packages: WP1 – retrofit assessors and retrofit coordinators, WP2 - installation of domestic insulation measures and WP3 - installation of domestic heat pumps. 8,605 courses were delivered with £7.58 million funding.
| Work Package 1 (RAs & RCs + Retrofit Advisors) |
Work Package 2 (Insulation) |
Work Package 3 (Heat Pumps) |
Total | |
|---|---|---|---|---|
| No. of courses completed | 1,301 RAs & RCs + 169 Retrofit Advisors |
1,642 | 5,493 | 8,605 |
The independent evaluation sought to assess the extent to which the competition had achieved its stated aims and objectives, and to identify successes and challenges around its implementation. It included interviews with DESNZ and MNZH staff involved in the HDSTC, interviews with providers offering funded training and a survey of trainees.
See the executive summary of the Phase 1 evaluation. The full evaluation report can be found on the Midlands Net Zero Hub’s website.
Main evaluation findings
The main evaluation findings included:
a. High trainee satisfaction
Satisfaction levels were strong across all three work packages (WP1: 73%, WP2: 92.9%, WP3: 74%). Trainees reported high satisfaction with training delivery, course content, and duration. However, fewer trainees were satisfied with opportunities to apply their skills in practice, with some calling for more supervised installations or assessments during the course.
b. Enhanced sector-specific and technical skills
Over four-fifths of trainees reported gaining the relevant technical and sector-specific skills aligned to their work package. This increased confidence has enabled many to undertake new types of work and positions them to benefit from growing demand in energy efficiency.
c. Greater supply chain engagement
The competition helped increase the number of trainees and businesses engaging with DESNZ retrofit schemes. Around 20% of surveyed trainees planned to work on government retrofit or decarbonisation schemes following their training.
d. Value-for-money benefits
The scheme delivered a wide range of benefits for both trainees and organisations:
- Employment Outcomes: Of 23 trainees who were unemployed at the start of training, 11 trainees secured employment as a direct result.
- Workforce Productivity: Employers reported improved work quality, faster delivery, and reduced costs
- Business Performance: Nearly one-third of trainees and most employers reported improvements such as increased contracts, turnover, reduced costs, and higher profit margins.
- Decarbonisation Impact: More firms are now involved in energy efficiency and retrofit projects, contributing to wider decarbonisation goals.
e. Development of transferable skills
Trainees gained broader skills including better understanding of retrofit markets, client benefits, time management, resource planning, and attention to detail.
f. Increased access to training
Providers noted that trainee numbers were significantly higher than would have been possible without the competition. Subsidised and free courses enabled 11 of 17 employers to train a wider pool of staff, helping businesses prepare for future demand.
g. Commercial benefits for providers
Training providers reported increased revenues, improved profit margins, greater market visibility, and reputational gains from participating in a government-backed scheme.
h. Operational challenges
Some providers raised concerns about the application timetable, suggesting it should avoid peak periods such as summer holidays to better accommodate educational institutions. Smaller providers also found the frequency of monitoring and reporting—weekly learner logs, fortnightly and monthly submissions—burdensome.
3. Home Decarbonisation Skills Training Competition Phase 2
HDSTC 2 was launched in July 2023. 24 training providers received funding to deliver training under 2 work packages: WP1 - retrofit assessment and coordination & WP2 - installation of domestic insulation measures. 7,309 courses were delivered under the competition with £6.77 million funding. Training on installation of Heat Pumps was not included in this competition as this is being supported by the Department’s Heat Training Grant.
| Work Package 1 (RAs & RCs) |
Work Package 2 (Insulation) |
Total | |
|---|---|---|---|
| No. of courses completed | 1,792 | 5,517 | 7,309 |
The evaluation of this Phase of the competition built upon the evaluation of Phase 1 to assess outcomes generated for Phase 2 trainees and investigate longer-term outcomes that may have been generated for Phase 1 trainees. It involved a follow-up survey with Phase 1 trainees, as well as a survey of trainees who completed a Phase 2-funded course.
See the executive summary for the independent research survey carried out for the Home Decarbonisation Skills Training Competition: Phase 2. The full evaluation report can be found on the Midlands Net Zero Hub’s website.
Main evaluation findings
The main evaluation findings included:
a. Strong trainee satisfaction
Most trainees were satisfied with their courses, with 77% of WP1 and 78% of WP2 respondents reporting they were ‘satisfied’ or ‘very satisfied’. Satisfaction was particularly high regarding course delivery and content.
b. Skills development and confidence
A large majority of trainees—80% of WP1 and 71% of WP2—reported gaining new sector-specific and technical skills. Many expressed increased confidence in undertaking retrofit assessor/coordinator or insulation installation work.
c. Workforce engagement with government schemes
Completion of accredited courses has enabled trainees to access work through government schemes. Up to 34% of survey respondents had already undertaken work or planned to do so within 6 -12 months. Additionally, 28% of WP1 and 17% of WP2 respondents reported an increase in the proportion of their working time spent on retrofit-related activities.
d. Importance of subsidised training
Cost was the most frequently cited barrier to training. Notably, 40% of Phase 2 respondents stated they would not have participated without free or subsidised courses. Subsidisation was a key factor in business decisions to engage with the competition.
e. Commercial benefits and career progression
Compared to Phase 1 follow-up responses, Phase 2 trainees more frequently reported tangible commercial benefits. These included increased work opportunities, promotions, pay rises, and new jobs. Overall, 62% of trainees felt the competition had significantly helped overcome cost barriers to training.
f. Ongoing skills development
The competition has encouraged continued learning. Since completing Phase 2 training, 31% of WP1 and 16% of WP2 respondents had undertaken further training. Among Phase 1 follow-up respondents, 44% reported completing additional retrofit or installation training, highlighting the scheme’s role in fostering ongoing professional development.
g. Course completion challenges
Despite positive outcomes, 22% of course enrolments did not result in completion. Reasons included short delivery windows, changes to work commitments or personal circumstances, and some trainees feeling they had gained sufficient skills without completing final assessments.
4. Warm Homes Skills Programme: How evaluation findings and programme review informed programme improvements
To support the government’s Warm Homes Plan ambition, the Department launched a new £8 million Warm Homes Skills Programme on 30 April 2025 to continue to train and upskill the workforce the retrofit supply chain. Successful training providers have been notified, and Programme-funded training will commence shortly. The first phase of the programme will run until July 2026, offering subsidised training opportunities for up to 9,000 installers and retrofit professionals based in England. The main change to previous skills competitions is that, in addition to funding courses in retrofit assessment & coordination and insulation installation, there will be opportunities for people to develop skills in areas that include fitting solar panels and working in non-domestic buildings.
Heat Pump training will continue to be funded by the Heat Training Grant.
How evaluation findings have informed programme improvements
a. Application timetable
Issue: Some providers felt that the application timetable could have been more considerate of work pressures including avoiding the summer holidays to better enable educational institutions to apply.
Action taken: The Warm Homes Skills Programme was launched in April, earlier than previous skills competitions, proving colleges with sufficient time to prepare and submit applications.
b. Course non-completion
Issue: A significant proportion of learners (22%) did not complete their course due to short delivery windows, eligibility issues, communication gaps, funding delays and underestimating the course difficulty.
Action taken: The application process has been refined. Priority is now given to accredited courses leading to recognised qualifications. Data collection methods have been improved to enable targeted interventions. Training is no longer provided entirely free at the point of consumption, to improve attendance and completion rates.
c. Frequency of reporting
Issue: Training Providers found the fortnightly reporting led to inconsistency with delivery numbers reported in the weekly Learner log and monthly report, while imposing complex reporting requirements on training providers. Also, the use of 3 separate reporting documents led to recurrent numeric inconsistency in the reports when collated.
Action taken: Reporting has been streamlined. Providers will now submit a single monthly reporting database, thus maintaining the required granularity while reducing administrative burden on providers.
Other improvements informed by programme review and stakeholder engagement
a. Delivery timeline
Issue: Some of the courses offered on the scheme could not be completed within the short delivery timeline, in particular Retrofit Assessor & Coordinator training, and the uncertainty of possible extension to the limited delivery timeline often deterred potential learners from enrolling on courses with lengthy completion timeline.
Action taken: To help address this, a longer delivery timeline of 12 months has been given for the Warm Homes Skills Programme (WHSP). This will mean that Training Providers will not relax their recruitment drive due to the uncertainty and trainees should not be deterred from enrolling on longer courses of 9–12-month duration.
b. Joining up on the department’s schemes
Issue: Grant programmes were not sufficiently joined up with capital schemes. The track through of competition trainees into capital schemes is sub-optimal, greater focus is needed on raising awareness of the routes to accreditation and the commercial opportunities in the schemes.
Action taken: There has been greater engagement with the Department’s scheme providers, and a wider range of courses available for funding such as solar installation and non-domestic courses to line up with the retrofit programmes.
c. Quality assessment / site visits
Issue: To further improve the quality of installation work, it has become essential for robust assessments to be made of the training delivered under the competition.
Action taken: An independent quality assessment contractor will be procured to conduct the quality assessment and site visits. This will be more robust than in previous competitions, consisting of reviews of course material, site visits, feedback surveys and reviews of the staff and tutors’ competence. This will be supplemented by a clearer KPI on training quality delivery and closer join-up with the oversight provided by Ofsted inspections of independent training providers and Further Education colleges.