In partnership with the Scottish and Northern Ireland Plumbing Employers’ Federation (SNIPEF), we are giving experienced plumbing and heating professionals, who have just undertaken heat pump training, a heat pump to install in their own home. Interviews with heat pump installers and industry experts reveal a gap between heat pump training and the ability of heating engineers to confidently incorporate heat pump installation into their commercial offer to householders. We want to understand whether doing their first heat pump installation in their own home means they have a more successful journey to offering heat pump installations in their business and career.

Our digital report is designed to make it easy to find the information you need. Start by learning what we are doing and why to understand the project’s purpose. Check where we are in the project for the latest updates. See who is taking part to learn about the participants. Find out why installers joined and what their training is like. Finally, see what’s coming next as the project moves forward.

Our key finding

This interim report confirms that there is a cohort of installers who are eager to start their heat pump journey in their own home and the Start at home scheme is feasible to implement. While these preliminary insights provide valuable early indications, the report does not explore whether the Start at home project has successfully helped participants to offer heat pumps as part of their plumbing and heating offer to customers. This will be explored in the final June 2025 report.

Many more skilled heat pump installers are needed to reach the UK’s net-zero targets. Figure 1 displays the Heat Pump Association’s (HPA) projection of installers needed each year to reach the target of 600,000 heat pump installations annually by 2028. This broadly echoes our own forecast, which was that the heat pump sector needs to grow by 4,000 to 6,000 installers per year. To achieve this, one of the biggest challenges to overcome will be recruiting enough skilled installers to meet demand.

Encouragingly, the number of heating professionals attending heat pump training is increasing, as reported by the HPA (figure 2).

However, these numbers do not necessarily translate into a growing active heat pump workforce. Recent estimates from a DESNZ survey of newly trained installers suggest that only 27% (out of 121 installers) have begun actively installing heat pumps after completing their training. While these numbers are expected to rise – especially since around half of the respondents had completed their training within the six months leading up to the survey – it does indicate that general plumbing and heating engineers face challenges when entering the heat pump industry.

Interviews with heat pump installers and industry experts reveal that newly-trained installers face several challenges when trying to secure their first few heat pump jobs. For instance, many installers struggle to attract their first customer and achieve MCS certification. Additionally, they often feel uncertain about their practical skills, are daunted by the paperwork, and may even still have doubts about the effectiveness of the technology.

Supporting existing plumbers and heating professionals to incorporate heat pump installations in their portfolio of work is the quickest way to create a skilled competent and confident workforce able to perform consistently high-quality installations in homes across the UK. We believe that facilitating the first installation for plumbing and heating professionals is key to encouraging more professionals to enter the marketplace with more confidence and better skills.

In the Start at home project, we are testing whether giving newly trained heat pump installers first-hand experience from installing an air-source heat pump in their own home helps accelerate the transition of their business to retrofit heat pump installations after course completion, boost their confidence in their skills and the technology, and increase customer attraction.

The project started in November 2023 and will run until the end of June 2025. This section provides an overview of the milestones reached so far.

Recruitment process

With the support of our partner SNIPEF, we’ve recruited 36 heating professionals to take part in this pilot project, from within SNIPEF’s membership of plumbing and heating professionals who are owners of microbusinesses.

There are several reasons why we wanted to recruit microbusinesses. This term is usually used to indicate businesses with fewer than 10 employees – in practice, we allowed slight flexibility to go a little over this number in considering eligibility for the project.

First, the heating sector is dominated by small-sized businesses, with 95% sole traders of microbusinesses (fewer than 10 employees) and 5% small businesses (10-49 employees). In piloting the Start at home project with them, we ensure that we are designing a solution that suits most plumbing and heating businesses in the UK.

Second, they are the organisations that face the greatest challenges when entering the heat pump industry. They often have less capital and less capacity to invest which makes them more risk-averse. Also, as businesses build on reputation with their customers, they need to be confident they can do high-quality work without needing to spend precious time and cost returning to homes to undertake remedial work.

Third, by recruiting individuals in leadership roles in their business (typically business owners) we ensure that we test the appeal and feasibility of a scheme like Start at home with those who can influence the trajectory of their business and ensure that heat pump installation is included in their business portfolio.

Figure 3 illustrates the recruitment process. Project participants were self-selecting, responding to an email sent in early May 2024 by SNIPEF directly to their members. In the call for interest, businesses were told that they would receive free heat pump training (paid for by SNIPEF’s charitable fund – note that heating engineers in Scotland do not have access to the Heat Training Grant, although there are ad-hoc funds available). They were also told that they would have an opportunity to receive a free air-source heat pump to fit in their own home (paid for by Nesta). Out of the entire SNIPEF membership, 90 businesses opened and engaged with the content linked in the call for interest. Importantly, over half (53%) of those who engaged expressed an interest in taking part in the project.

Following discussions with interested businesses, screening against our selection criteria, and some dropouts later on, we were able to confirm 36 participants in our pilot, 40% of those who responded to the expression of interest. Two participants withdrew from the project as they were not able to attend training courses. Since the project started, five participants declined the heat pump offer and asked to be moved to the comparison group – training only pathway – and these heat pumps were offered to other participants.

Heat pump and low temperature training

All participants attended both a ‘level 3 air-source heat pump systems’ course and a ‘low temperature and hot water heating system’ course (examples of the qualification frameworks here and here). Eight participants had already completed their level 3 air-source heat pump systems training and one participant had already completed both courses before joining the project. However, while a few participants had already completed the heat pump installation course, none installed a heat pump in a retrofit. In total, 68 courses were booked as part of the Start at home project through several training providers selected by SNIPEF. All training planification and costs were covered by SNIPEF through their charitable fund.

Research activities

We designed a range of research activities to capture participants’ experiences over the course of the project. The findings from the activities that have so far been completed are discussed in the following sections. After the recruitment process was completed, we conducted a baseline survey with all participants in July 2024. The purpose of the survey was to capture their attitudes and knowledge levels about heat pumps before attending training, as well as their hopes and fears as they started the project. We intend to run the survey again in April 2025 to measure any change over the year.

We also conducted semi-structured qualitative interviews with 24 out of 36 participants between November and December 2024. All interviews were conducted on Zoom or over the phone, depending on the participants’ availability and preference. The aim of the interviews were to understand their plumbing and heating career, their training experience, their knowledge of and confidence in heat pump installation, as well as their expectations for the year ahead. During the analysis, nine interviews were randomly selected to identify recurring themes. The remaining 15 interviews were then coded against this framework to classify the qualitative insights from all interviews and allow for content analysis. In the following sections, we explore participants’ profiles, their motivations for joining the project, and their reflections on the training.

Heat pump installations so far

As part of the Start at home project, 20 newly trained installers have started working on their home installation – these are in the ‘heat pump at home’ pathway of the project, while the remaining 16 are in the ‘training only’ pathway. We initially did a random prize draw to select 20 individuals out of our 36 participants in line with the agreed funding for the project. Five subsequent draws were conducted to reassign heat pumps that other participants had had to decline. Ultimately, while we intended to run a draw, most participants have had a chance to receive an air source heat pump making participation almost entirely self-selecting, and 20 confirmed their interest and availability to install it in their own home by the end of March 2025. Reflecting on the delivery of the project, asking plumbing and heating engineers to attend training in autumn and install a heat pump in their home during the winter months is a huge task, and the fact that 20 individuals were motivated to undertake this provides strong evidence of the appetite of a scheme like Start at home.

At the time of writing, 13 heat pumps have either been delivered to the installers or a final quote is being agreed upon. Among those, 5 heat pumps are already up and running.

We are working with City Plumbing to order and deliver heat pumps to installers. Participants in the ‘heat pump at home’ pathway were able to choose their preferred manufacturer and an installation kit was provided alongside the heat pump unit, including a hot water cylinder (pre-plumbed or standard), diverter valve, buffer (if required), feet, hoses, necessary manufacturer’s controls, filtration, frost protection, sealed system kit, and external pipe insulation. The current average cost for a heat pump installation kit (including VAT) is £8,000.

At the project's inception, we had expected that participants would also be able to receive funding from Home Energy Scotland's grant and loan scheme to fund other elements of their heat pump system. However, there has been some doubt as to whether installers would be able to claim the funding. Consequently, so far in the project, no installer has claimed HES funding. In future delivery of similar schemes, it will be important to ensure that participants are also eligible for government funding or incentives, given the indications that this type of scheme is likely to have high public value.

Participation in the project was targeted, by design, to those who are owners – or in other senior/responsible positions – of microbusinesses. Through our qualitative interviews, we verified that we have reached the target group profile we had intended. This section explores that profile in more detail. Note that all participants were men, which is reflective of the overwhelming majority of men in the plumbing and heating workforce.

Start at home project participants are sole traders or small family businesses, with the largest business involved in the project having a total headcount of 12 people. Most people described their business as a ‘family business’, employing at least one family member (often their son, but also a spouse or parent) and one or two other employees, often apprentices. One heating engineer states:

Many of the companies involved are staffed by the owner who continues to be active ‘on the tools’ on a daily basis while dealing with administrative tasks as well. As one interviewee describes:

Overall, the people we spoke to are time-poor and divide working time between many different responsibilities, while still being flexible. One engineer explains how they are:

This matters for the Start at home project as they need to find the time to do a full heat pump installation alongside all the other work that they do. For example, we heard from some participants that they typically work on their installation in the evening or during the weekends.

Unsurprisingly, the people we spoke to describe themselves and their respective businesses as being busy year-round, particularly throughout the winter heating season. Most also describe their customer base as returning customers, getting customers from word-of-mouth and not needing to advertise much to get sufficient business to fill their capacity, although some mention online advertising as a way to attract new customers. A few participants also explained being subcontracted for commercial work. Some engineers also described themselves as having existing links to particular brands in the heating industry – for example being an accredited installer for a given manufacturer.

Most participants have been in the trade for some time – often for over 10 years. This means that all of them are experienced heating engineers, with established businesses and customer bases. Many went into plumbing and heating through an apprenticeship, having immediately left school. A few people told us they were introduced to the trade by their father, who was also in the trade. For example, two heating engineers explain:

However, there are a couple of project participants who joined the plumbing industry having previously worked in other industries or having had a first career.

The businesses involved in Start at home also typically cover most aspects of plumbing and heating, mostly domestic. Each of our project participants tends to have a diverse customer base and a wide range of income sources for their business. Many of them describe themselves in terms equivalent to “no job too big or too small”, or doing “bits and pieces of all kinds of plumbing and heating works”, reflecting that they would cover a wide range of plumbing and heating tasks. Many participants describe the polyvalent nature of the job and the wide range of situations they encounter day-to-day:

We had intended to recruit individuals with no prior experience with heat pumps, that is, companies that are currently not offering heat pump installations to their customers. This was so that project participants would be in the very earliest stages of transitioning their business to heat pumps.

Interestingly, in practice, this was more difficult to apply, as some potential participants had only a little experience installing heat pumps under supervision. Some participants describe their installation experience as “hand-held, just doing what [they] were told”. As one engineer describes, “They just gave us a big schematic and we followed it. Their engineer came out, checked it over and signed it off. We were left not really knowing much else about them.” Others echo this installer’s experience, “I have fitted heat pumps on sites that we've been on, but that's as an installer, not as a main contractor, or knowing to do MCS or anything like that.” In these circumstances, the other company had done the design and commissioning of the heat pump.

The findings from our baseline survey found that participants thought heat pumps are a good alternative to gas boilers for private homes in Scotland, as shown in figure 4 – which makes sense as participation in the Start at home project was voluntary. This survey was conducted prior to the training courses. However, some participants appear to have reservations: 31% of respondents indicated that they neither agree nor disagree, while 8% disagreed with the statement.

This suggests that the Start at home participants were motivated to take part in the project because they could see a place for heat pumps in the Scottish domestic heating sector, which is illustrated by the quotes in this section. Yet, participants also expect that the entry into the heat pump sector might be slow and challenging, as shown in figure 5.

We hypothesised that to feel confident that a large scheme based on the Start at home model would be of interest to the plumbing and heating industry, the motivations stated by participants should refer to the key features of the Start at home intervention. To analyse the interviews, we categorised engineers’ motivations into broad themes and compared them based on the frequency of mention during the interviews. We found that the characteristics of the Start at home intervention were a key factor for joining, as shown in figure 6.

The most mentioned set of motivations for joining the Start at home project refers to the timely nature of the project – 48 references. These motivations include the desire to future-proof their business, stating that heat pumps in general are the future of the industry. As two engineers explain:

Even when some explained that they didn’t expect to install many heat pumps themselves, they still felt preparation would help the long-term success of the business, given many would likely pass it on to a family member or employee.

This first set of motivations also includes wanting to get a head start on competition. One interviewee describes wanting:

Overall, this emphasis on the timely nature of the project matches the results from our survey showing that they generally believe that heat pumps are a good solution for home heating (figure 4).

Most notably, we find that the features of the Start at home intervention itself, and the barriers that it removes, are the second most mentioned set of motivations – 42 references. One installer highlights the learning opportunity that Start at home represents, which attracted him to the project.

Others pointed out that the Start at home intervention was appealing because it gives them the opportunity to kickstart their move into heat pumps, through the opportunity of free training and the practical option to put it into practice “right through, from start to finish.”

Many participants also point to the appeal of testing things out in the comfort of their own home to better advise customers altogether:

The third most cited set of motivations refers to broader societal change – 41 references. These include the increasing salience of green discourses, the recent changes in legislation (such as the Future Homes Standard) and the fact that heat pumps are becoming more common and customers now ask about heat pumps. As a couple of installers state:

Overall, these motivations are consistent with previous surveys of the industry, such as the survey conducted by Vaillant in April 2023. They find that the top motivators for heating professionals looking to enter the heat pump sector are future-proofing their business, personal financial benefits from widening their portfolio, and supporting the net-zero agenda. Yet, our findings suggest that the key features of the Start at home intervention – access to training and the opportunity to do a first heat pump installation in your own home – are appealing to plumbing and heating professionals and create a separate set of motivations. The enthusiasm for these features signals that there is both a need and appetite for such initiatives within the sector. This is encouraging for the scalability of the project, as it suggests that extending the programme beyond the pilot phase could attract a similarly motivated group of professionals, enhancing the potential for wider adoption and success.

As shown in figure 7 – which displays the results of the survey we conducted in July 2024 before the participants attended training – while some participants reported having some knowledge of heat pumps, the majority had relatively little.

In some cases, the interviews revealed how installers gained their knowledge of heat pumps. Some installers explained that many elements of heat pump systems are similar to other types of systems, being “just another heat source”, “much the same” and “not anything confusing, not hard to get right” and are therefore not completely unknown to them. Others gained experience having fitted some heat pumps in new builds. One installer told us:

For those with limited knowledge about heat pumps prior to the training, they highlighted the difference between heat pumps and other heating systems such as gas and oil, and the gap between “doing something on paper or watching a video” and “actually experiencing it [a heat pump installation] yourself”. Others mentioned the different sets of skills required to install heat pumps, as this quote illustrates:

These findings highlight the diversity in knowledge levels among the Start at home participants before they attended the heat pump training, which is worth noticing as it may shape expectations about and experience of the training, separated from factors related to the delivery and content of the course itself.

Overall, for many participants, training led to increased knowledge, covering heat pumps and how they function in-depth and building confidence in their knowledge of the technology – 46 references. One installer explained how the training “helped me no end at all because I understood it a whole lot better. It took going to the college, the training centre for that … it really did make me understand it a whole lot better.” The low temperature and hot water heating system course was especially praised by participants, as illustrated by this quote:

Participants also commented on the breadth of knowledge and experience of the trainers:

Some participants even mentioned changing their mind about heat pumps as a result of their discussions with peers and trainers:

Yet a common theme about the training experience was that it lacks practical aspects and often it is not sufficient to feel confident about doing a heat pump installation for a customer. Factors mentioned by participants include needing the training to be ‘more hands-on’ and focused on ‘how the heat pump works’, learning by ‘making the mistakes’, rather than focusing on ‘theory’ and ‘heat loss calculations’. As one business owner explains, the training should be:

Several heating engineers summarised how they felt after the training by highlighting that:

This shows that confidence in one’s own skills and confidence in the technology may discourage installers from moving into retrofitting heat pumps for their customers, even after attending training.

Importantly, what many installers identify as needed to feel more confident are the specific opportunities that the Start at home intervention provides. That is, the chance to practice skills doing a retrofit in an existing property without the pressure of doing it for a customer, as well as seeing how the heat pump performs and learning to improve the efficiency of the heating system as the installer lives with the heat pump. Overall, these findings suggest that a scheme like Start at home would complement the existing training available to plumbing and heating professionals.

Over the next 4 months, we will continue research activities with the Start at home installers. We will touch base with all participants through a second round of qualitative interviews at the end of April and in May to see how they are doing with the heat pump side of their business and assess the impact of doing a first installation at home on reported levels of knowledge and confidence. To gather additional insights, we will survey all participants, which will provide useful indicators and complement the findings from the interviews. We’ll reveal the final findings from the Start at home project at Installer Show 2025 – make sure to come along to the Nesta stand if you would like to learn more about the outcome of the project.

We want the learnings from this project to inform existing and new efforts to train an active and skilled workforce which will be ready to respond to the growing demand for heat pump installations. Alongside the research activities, we will continue to engage industry actors to think about the different ways to scale this scheme to all heating professionals in the UK. If the UK is to meet its current net zero goals, the low-carbon heating industry must expand. Helping existing plumbers and heating engineers transition to working with heat pumps is the quickest way to ensure the sector has the engineers needed to successfully move the UK’s heating system away from fossil fuels. To help us think about scaling, we will continue meeting with members of our scaling group which includes national and devolved governments, manufacturers, training providers and other industry organisations, to deliver ways to design and deploy a broader scheme based on the Start at home model.

To support our engagement with industry experts, we have put together a devoted team to specifically explore and support routes to scales, as we believe that the Start at home scheme has the potential to offer existing plumbers and heating professionals the help they need to confidently enter the heat pump sector. If you want to take part in these discussions, get in touch with the Start at home team ([email protected]). In the meantime, stay tuned for more findings in the coming months.

We would like to thank our partner SNIPEF and the Nesta project team (Robin Parker, Benoit Siberdt, Oliver Zanetti and David Bleines) for their support on this project.