If you live in a house, the heat pump decision is relatively straightforward: find an MCS-certified installer, apply for the Boiler Upgrade Scheme grant, and get it installed. If you live in a flat, almost everything about that process gets more complicated. Not impossible — but you’ll need to navigate a set of challenges that most of the public-facing guidance on heat pumps doesn’t really address.
About 5 million households in England and Wales live in flats, and a substantial proportion of those are leaseholders rather than freeholders. That distinction matters enormously for what you can actually do to your property.
The Leasehold Problem
A leasehold flat is one where you own the flat itself but not the building it sits in — the freehold of the building belongs to someone else (the freeholder, often managed through a managing agent or residents’ management company). Your lease will contain terms about what you can and can’t do to the property, and most standard leases include provisions that require freeholder or managing agent consent before making structural alterations or installing equipment that affects the external appearance of the building.
A heat pump — any kind that involves an external unit — almost certainly falls into this category. An air-to-water heat pump’s outdoor unit is typically wall-mounted or ground-mounted outside the building. An air-to-air split system has an outdoor unit that goes on an exterior wall or balcony. Either way, you’ll likely need permission before you can install one.
Getting that permission is possible, but it’s not guaranteed, and the process can be slow. Freeholders and managing agents vary enormously: some are proactive and will grant consent quickly, others are difficult, and some require you to use their approved contractors (which can increase costs significantly). If the building is in a conservation area or has listed building status, planning consent may also be required on top of the lease consent process.
The practical first step is to read your lease — specifically the alteration clauses — and contact your managing agent or freeholder early to understand their position before you spend time and money getting surveys done.
Air-to-Air: The Most Practical Option for Most Flats
For flat-dwellers who want to install their own individual system, air-to-air heat pumps are the most realistic option in most cases, for a few reasons.
Air-to-air systems (split systems) heat and cool air directly, without any connection to a wet heating system. They don’t replace your hot water cylinder — you’d still need a separate means of heating water — but they can provide space heating and cooling very efficiently. A modern split system typically has a coefficient of performance (COP) of 3–4, meaning three to four units of heat for every unit of electricity consumed.
The installation is simpler than an air-to-water system: an outdoor unit, an indoor wall-mounted unit, a refrigerant line connecting them through the wall, and an electrical connection. The outdoor unit is smaller and lighter than an air-to-water unit, which matters when you’re talking about balcony installations or wall brackets on an upper floor.
From April 2026, air-to-air heat pumps became eligible for a £2,500 government grant — but there’s an important catch. That grant is only available to homes currently heated by direct electric heating: storage heaters, electric panel radiators, electric underfloor heating. If your flat currently has gas central heating, you don’t qualify for the air-to-air grant. You’d need to look at the £7,500 Boiler Upgrade Scheme for an air-to-water system instead, which brings its own complications in a flat context.
Even without the grant, air-to-air can make economic sense as a supplement to or replacement for storage heaters, particularly in flats where the heating system is ageing and expensive to run.
What You’ll Need to Sort Out Before Installing
Freeholder/managing agent consent. As discussed — check your lease and get consent in writing before proceeding. Some freeholders have standard conditions (approved contractors only, unit placement requirements, reinstatement obligations when you sell).
Planning permission. In most cases, air-to-air split systems for flats fall under permitted development rights and don’t require planning permission — but this is not universal. Flats in conservation areas, listed buildings, or in certain blocks where permitted development has been removed will need planning consent. Check with your local planning authority if you’re uncertain.
Building regulations. Electrical work must be carried out by a Part P certified electrician. The refrigerant connection requires an F-Gas certified engineer. Your installer should be qualified for both; if using separate contractors, verify qualifications before work starts.
Structural assessment. If the outdoor unit is going on a balcony or wall bracket, a structural check that the fixing point can take the load is sensible, especially in older buildings.
Heat Networks as an Alternative
For flats in larger blocks, a heat network (sometimes called district heating) is often a more practical route to decarbonised heating than individual installations. A heat network serves the whole building from a central plant — a heat pump, a biomass boiler, or some combination — distributing hot water to individual flats through insulated pipes.
You don’t install anything in your flat beyond a heat interface unit (HIU) — a box roughly the size of a gas meter cupboard. You don’t deal with external units, freeholder consent for equipment installation, or building regulations for individual appliances.
The challenge with heat networks is that they’re a building-level decision, not a flat-level one. Unless your block already has a heat network — or is in an area covered by a district heating scheme — you can’t install one yourself. If you’re buying a flat and decarbonisation is important to you, checking whether the building has or is planning a heat network is worth doing.
Practical Takeaways
The heat pump path for UK flat-dwellers in 2026 isn’t as straightforward as the government’s communications might suggest. It’s navigable, but it requires:
- Reading your lease and understanding your freeholder’s position before doing anything else
- Checking whether you qualify for any of the available grants (the £2,500 air-to-air grant has strict eligibility around existing electric heating)
- For air-to-air installations: confirming permitted development rights for your specific property and location
- Using appropriately qualified installers (MCS certification for heat pumps, Part P for electrical, F-Gas for refrigerant)
If your building has a heat network or is planning one, that’s worth exploring as an alternative to individual installation — particularly if your lease makes individual external equipment installations difficult.
The broader point is that the UK’s push towards heat pump adoption has been designed primarily around the housing stock that’s easiest to adapt: owner-occupied houses with existing gas boilers. Flat-dwellers — especially leaseholders — are a harder case that requires more targeted support and clearer guidance than currently exists. In the meantime, knowing the landscape is the first step to making it work for your specific situation.