Engineers Are the Asset: Workforce Age and the HVAC Valuation

The ArithmeticThe register is getting older and the pipeline is not keeping up

Gas Safe's decade review put the average age of an engineer on the register at 45.4 in 2023, and a large cohort of that workforce is approaching retirement, a point the industry's own reviews keep flagging. The numbers on the low carbon side are more specific: DESNZ modelling has put the requirement at around 50,200 heat pump installers by 2030, against roughly 9,000 MCS certified heat pump installers today.

For a business owner those are abstract figures until you try to recruit. For an acquirer they are the central assumption in the model, because an acquisition in this trade is usually a way of buying engineers who already exist rather than competing for engineers who do not. That is the reason a firm with eleven certified engineers and low turnover in the team commands attention that its accounts alone would not explain.

It follows that the question a buyer asks about your staff is not how many you have. It is how long they have been with you, what they hold, and what happens to them the day you leave. Those three answers are worth more than a strong year.

That is the reason a firm with eleven certified engineers and low turnover in the team commands attention that its accounts alone would not explain.

The EvidenceWhat retention looks like when somebody else has to verify it

Retention is claimed in every sale and evidenced in very few. What stands up is dull: length of service by individual, leavers over three years with the reasons where you know them, the training the business has paid for and when, and whether pay has moved with the market or lagged it. A buyer can check most of that against payroll in an afternoon, and they will.

Contracts of employment are read next, and this is where owner-managed businesses are usually exposed. Long-serving engineers on a two-page contract from 2009, no post-termination restrictions, nothing about company vehicles or tools, and nothing written down about the training the business funded. None of that stops a deal. All of it becomes a warranty conversation, and warranty conversations move money from completion into deferred consideration.

The strongest single piece of evidence is a supervisor who is not you. Somebody who quotes work, allocates labour, deals with the difficult customer and holds a relationship with your largest account. That person is what converts a claim about the team into a business that a buyer believes will still function in month three, and appointing them is a twelve month job rather than a decision.

The TimingRetention is built in the years before, not the weeks after

Everything above is slow. Length of service accrues at one year a year. A supervisor grows into the role over eighteen months of being allowed to make decisions and occasionally getting them wrong. Training cycles run to the assessment calendar rather than to yours. This is the part of preparing a business for sale that genuinely cannot be compressed, and the reason I keep telling owners that a two-year runway is worth more than a good quarter.

It is also the preparation that pays whether or not you sell. A business with a second decision maker, documented contracts and a team that stays is a business the owner can take a fortnight off from. Owners tend to discover that the year they spend making themselves less necessary is the year they start enjoying it again.

One caution on cost. Employer National Insurance rose to 15% on 6 April 2025 and the threshold at which it starts fell to £5,000, which has changed the arithmetic of employing people this year. It is a real cost and it belongs in your figures, but it is not a reason to hold headcount down ahead of a sale, because the thing you would be economising on is the asset being bought.