How much do heat pumps for landlords cost?

The honest answer to what a heat pump costs a landlord is that it depends on the property, but the figures are far more predictable than most installers let on. For a single rented house or flat, an air-source heat pump usually lands between £9,000 and £16,000 fully installed before any grant. The £7,500 Boiler Upgrade Scheme grant, which is open to landlords for domestic properties in England and Wales up to 45kW, brings the net cost down to roughly £2,000 to £9,000 on a typical conversion. Where you sit in that range is driven mainly by how many radiators need upsizing and how awkward it is to site the external unit, not by the heat pump itself.

What actually drives the price

Three things move the number more than anything else. The first is the emitters. Most rented houses have radiators sized for an old gas boiler running at 70 to 80C. A heat pump runs best at a lower flow temperature, typically 45 to 55C, which lifts the efficiency and protects your tenants from bill shock. To get that low flow temperature, some radiators usually need upsizing. We survey the existing emitters before we quote so the upgrade is priced in, never sprung on you later.

The second is the hot water cylinder. Combi boilers heat water on demand, but heat pumps work with a stored cylinder, so a property switching from a combi will need a cylinder added, which takes up an airing cupboard's worth of space and adds to the cost. The third is the fabric. A heat pump fitted to an under-insulated, draughty house will struggle and run expensively, so loft and wall insulation often needs to happen alongside the install. That cost also lifts the EPC, which is the point of the exercise for most landlords.

Per-property and per-block ranges

A flat or small terrace conversion sits at the lower end, often £9,000 to £12,000 before grant. A larger house with several radiators to upgrade and a cylinder to add sits higher, £13,000 to £16,000. Communal systems are a different calculation entirely. A cascaded air-source heat pump replacing a shared boiler in a block of flats is sized on the building's peak heat loss rather than the number of units, and commonly runs from around £40,000 for a small block into several hundred thousand pounds for a large one. The Boiler Upgrade Scheme caps at 45kW thermal and is domestic-only, so larger communal plant looks to capital allowances rather than the grant.

How landlords pay for it

Most landlords fund single-property conversions from cash plus the Boiler Upgrade Scheme grant, which the installer typically claims on your behalf and deducts from the invoice, so you only ever pay the net figure. If you hold property through a limited company, the heat pump qualifies as plant and machinery, which means you can set the cost against corporation tax through capital allowances, an extra saving on top of the grant. Always confirm the tax treatment with your accountant, because how you hold the property matters. For larger portfolios and communal schemes, phasing the work, converting each property at the point its boiler fails rather than all at once, spreads the capital and avoids the trap of paying for two heating systems in the same property inside a decade.

The running-cost question

The figure landlords worry about most is not the install cost but whether the tenant's bills go up. Electricity costs more per unit than gas, but a heat pump with a seasonal efficiency, or SCOP, of 3.0 to 4.0 delivers three to four units of heat for every unit of electricity, which offsets most of that price gap. The single biggest lever is the flow temperature, which is why we design low and survey the radiators first. A well-designed heat pump in a properly insulated house runs at or close to gas running cost today, and the gap improves every year as gas carbon levies rise and the electricity grid gets cleaner. Where your tenants pay their own bills, a predictable low running cost is a genuine letting advantage.

Hidden costs to watch

The costs that catch landlords out are usually the ones a cheap quote leaves off. A BS 4142 acoustic assessment is commonly needed where the external unit sits close to neighbours, particularly on dense terraced and HMO streets. Older or larger properties may need an electrical supply check, and on bigger communal systems a distribution network operator supply upgrade can be the longest-lead and most expensive item. Scaffolding, making good after pipework runs, and the cylinder space all add up. We quote the whole job, including these items, so the fixed price is the price.

Comparing quotes properly

The performance figures on a heat pump quote should be given to the recognised standards, BS EN 14825 for SCOP and BS EN 14511 for rated COP, so you can compare one supplier's numbers directly against another's. If a quote does not state the design flow temperature, the SCOP, and the radiator survey findings, you cannot judge whether the running-cost promise is real. We would rather lose a job to honest maths than win it on a number we cannot stand behind. The cost ranges by system type below are drawn from real UK projects, not optimistic estimates.