The Boiler Upgrade Scheme grant jumped to £7,500 per air source heat pump in October 2023, and it’s still £7,500 in mid-2026. That single number has done more to reshape the UK’s heat pump installer market than any marketing campaign, and solar installers watching MCS install volumes climb are asking the obvious question: should we add ASHPs to the book?
It’s not a trivial decision. Heat pumps and solar PV sit in the same “electrify everything” story, but they are different trades with different failure modes, different margins and a different regulatory scope. This piece looks at the demand pull, what MCS certification actually requires, and whether the margin and skills reality stacks up against the hassle of adding a second product line.
The demand pull is real, but it’s grant-shaped
UK heat pump installs have been climbing steadily, helped by the Boiler Upgrade Scheme (BUS) grant of £7,500 for an air source heat pump (£7,500 for ground source too, with a separate higher-capacity biomass rate for off-gas rural properties). That’s a genuinely large voucher against a typical ASHP installed cost, and it has pulled a chunk of demand forward that would otherwise have sat on the fence comparing quotes against a gas boiler replacement.
Two things matter here for anyone weighing a cross-sell decision. First, BUS money only reaches consumers via MCS-certified installers — it is not a scheme homeowners can self-administer with an uncertified tradesperson, and the installer applies the voucher on the customer’s behalf. Second, the scheme has been extended and adjusted more than once since launch, and eligibility/property criteria (EPC status, no outstanding loft/cavity insulation recommendations, etc.) still trip up a meaningful share of applications. If you’re going to sell against the grant, you need someone in the business who understands the paperwork as well as the F-gas regulations.
It’s worth being precise about scope, because this is where installers get caught out in sales conversations: BUS does not cover solar PV or battery storage. It is a heating-system grant, full stop. The 0% VAT relief on residential solar and battery storage (in place in Great Britain until 31 March 2027, after which it’s scheduled to revert to 5%) is a separate mechanism that applies to solar and batteries, not heat pumps. Conflating the two in a sales pitch is the fastest way to lose a customer’s trust at survey stage — get this straight before your sales team touches the phones. For a clean breakdown of what’s actually available where, heatpumpinstallationgrants.co.uk is a useful reference to send customers who are confusing the two schemes.
MCS scope: heat is a different certification, not a bolt-on
This is the part solar-only installers sometimes underestimate. MCS (Microgeneration Certification Scheme) treats renewable heat and solar PV as separate certification scopes. Holding an MCS solar PV certification does not qualify a company to install heat pumps under MCS, and it doesn’t unlock BUS voucher eligibility either — that requires MCS certification specifically for heat pump installation (or working under an umbrella scheme with an MCS-certified installer of record).
In practice that means:
- A dedicated heat pump installer competency — either through direct MCS certification for the heat scope, or a qualified installation manager overseeing the work.
- Separate design and commissioning standards — MCS 021 (or its successor heat loss/emitter guidance) heat-loss calculations, radiator/emitter sizing, and system commissioning sign-off, which is a different discipline from a solar PV yield estimate and string design.
- F-gas handling qualifications for anyone touching the refrigerant circuit — a solar electrician’s Part P and G98/G99 grid-connection knowledge doesn’t cover this at all.
- Ongoing CPD and audit requirements specific to the heat scope, on top of whatever you’re already doing to keep PV certification current.
None of this is insurmountable — plenty of firms run dual MCS scopes successfully — but it is a genuine second certification programme, not a training afternoon. Budget for it as you would for opening a new trade line, because that’s what it is. commercialheatpumpinstallers.co.uk sets out what the certification and design workload looks like at the larger end of the market, which is a useful gut-check before committing resource.
The margin and skills reality
Here’s where the cross-sell case gets more nuanced than the headline grant number suggests.
Upfront cost and margin. A typical domestic ASHP installation, factoring in the unit, any necessary radiator or underfloor upgrades, a hot water cylinder swap, and commissioning, often lands in a similar bracket to a mid-size solar-plus-battery installation once BUS is applied — but the labour mix is very different. Heat pump installs lean more heavily on wet-trade skills (plumbing, heating design, emitter sizing) and less on the electrical first-fix and roof work that dominates a PV job. If your existing team is electrically-led, you’re either retraining people into a genuinely different discipline or subcontracting the heating side, and both routes eat into the margin the grant appears to promise.
Skills gap is the real constraint, not demand. The UK heat pump sector has talked about an installer shortage for years, and it hasn’t fully closed. Training pipelines (through manufacturers, colleges and MCS-approved training centres) have expanded, but experienced heat-loss designers and heating engineers who can size a system properly — not just bolt a unit to a wall — remain in shorter supply than the grant-driven demand would like. A rushed cross-sell with undertrained fitters is how you end up with undersized systems, unhappy customers running expensive backup immersion heaters through winter, and the kind of reputational damage that follows a company for years in a local market.
Where it works best. The strongest cross-sell cases tend to be:
- Installers who already do general electrical and renewables work and can partner with (or acquire) a qualified heating engineer rather than retrain from zero.
- Businesses in rural or off-gas areas, where the case against oil or LPG heating is much stronger than the case against mains gas, and where solar-plus-battery-plus-heat-pump bundles genuinely reduce a customer’s total energy spend.
- Commercial and light-industrial work, where heat pump projects are specified and project-managed rather than sold on a doorstep, and where the buyer already understands the compliance landscape. heatpumpsforbusinesses.co.uk is a decent illustration of how differently that conversation runs versus a residential BUS sale — it’s about operating cost and decarbonisation reporting, not a grant voucher.
Several installers in the SEO Dons network have already made this call in different directions, which is instructive. Carbon Legacy built renewables and heat pumps together as a single proposition from the start rather than treating heat as an add-on, and it shows in how the business is structured. YEERS runs solar, battery, heat pump and EV charging under one roof across Yorkshire, which is closer to the “full electrification” model the grant environment is nudging the market towards. By contrast, firms like ElectriFusion Solutions in South Yorkshire and ecoaim in Central Scotland have stayed focused on solar and battery, which is a perfectly rational choice if the local heating trade is already well served or if maintaining tight quality control on PV is the priority.
What the numbers actually support
It’s worth resisting the temptation to treat £7,500 as free margin. It’s a voucher that reduces the price the customer pays — it doesn’t change your cost base, and if anything it compresses the negotiating room a well-informed customer expects, because they know roughly what the grant is worth and will quote-shop accordingly. The businesses doing well out of the heat pump boom are the ones that treated MCS heat certification as a proper capital investment in a second trade, priced installs to reflect genuine heat-loss design work, and didn’t try to run heat pump fitting through electricians moonlighting between solar jobs.
For context on where the wider heat-and-power-electrification trade is heading, and how installer businesses are pricing dual-service offers, it’s worth cross-referencing against consumer-side cost expectations too — thecostofsolar.co.uk’s solar battery storage cost guide is a useful companion read for pricing conversations that increasingly bundle PV, battery and heat in one customer pitch, and thebritishsolarblog.co.uk covers the consumer-facing version of the electrification argument that heat pump sales teams end up making anyway.
The verdict
Adding ASHPs makes sense for solar installers who can either bring in genuine heating-design competence or partner properly with someone who has it, who operate in markets where the grant materially changes a customer’s decision (rural/off-gas particularly), and who are prepared to treat MCS heat certification as a real second-trade investment rather than a badge to slap on the website. It makes much less sense as a quick bolt-on sold by the same sales script that shifts solar, run by fitters given a weekend’s training on a new box. The grant has pulled demand forward — the businesses that will keep that demand once BUS eventually tapers are the ones building genuine heat-pump competence now, not just riding the voucher.
The market data supports patience over speed here: the installers scaling heat pumps successfully alongside solar are the ones who separated the certification, training and commercial planning from the sales pitch, rather than assuming solar credibility would carry over automatically. It doesn’t — MCS says so explicitly, and customers who’ve had a badly sized heat pump find out the hard way.