What the evidence says
The question "is my home suitable?" was tested directly by the Electrification of Heat demonstration project, led by Energy Systems Catapult and funded by the government. It installed 742 heat pumps in a mix of British homes and concluded that heat pumps can be successfully installed in all of the property types it tested. It did not find a type of home that ruled a heat pump out.
That matches what is already happening. Among heat pumps funded by the Boiler Upgrade Scheme in England and Wales, 55% replaced mains gas, 18% oil and 10% direct electric heating, across all kinds of housing. Suitability is less a yes-or-no than a question of what work the home needs.
The three things every home needs
Room for the heat pump
An air source unit needs an outdoor spot with space around it for air to flow, and a route for pipes into the house. A ground source system needs room for a ground loop and an indoor plant space. In England, an air source unit can often be installed without a planning application if it meets the national conditions, including a sound standard.
Room for a cylinder
Most heat pump systems store hot water in a cylinder. The government's explainer lists space for a cylinder as one of the things you need. Homes that switched to a combi boiler often removed theirs, so finding a place for one is a common job. The hot water guide explains why.
Emitters that work at lower temperatures
A heat pump is most efficient sending cooler water round the heating system than a boiler would. Radiators deliver less heat at lower temperatures, so some may need to be larger. The government's explainer says some radiators may need to be changed, and quotes Energy Systems Catapult that heat pumps can operate efficiently at moderate and high flow temperatures, which widens the options for homes that cannot change every radiator.
Homes that are usually straightforward
- Houses and bungalows with a garden or yard and an existing radiator system.
- Homes heated by direct electric heaters, where the price of a unit of heat falls most, or by a fuel that has to be delivered.
- Homes with underfloor heating, which already runs at low water temperatures.
- Reasonably insulated homes, where heat loss is moderate.
Homes that need more thought
- Flats. The outdoor unit needs a place, often on a balcony, a wall or the ground, and the building owner's agreement. Where there is no wet system, air-to-air is an option. Some buildings suit a shared system better.
- Homes with no outdoor space at all. A ground source borehole or a shared system may be the route.
- Listed buildings and conservation areas. Planning rules are stricter, and the national permitted development rules do not cover listed buildings.
- Very leaky homes. They can have a heat pump, but a large one; simple insulation first often makes the system smaller and cheaper to run.
Insulation: helpful, not a precondition
Insulation reduces the heat a home loses, which means a smaller heat pump, smaller radiator changes and lower running costs. Some measures are cheap and simple, such as topping up loft insulation and draught-proofing; others, such as solid wall insulation, are big projects. A heat pump can be designed around the home as it is, but it is worth doing the easy measures first, because they reduce the size of everything that follows.
How homes are heated now
The 2021 census found that 74% of households in England and Wales used mains gas alone, about about 2.1 million electric heating only and 865,940 oil only. For each group the question is slightly different: for gas homes the running-cost comparison is close, for homes with direct electric heating the price of a unit of heat falls sharply, and for oil homes the comparison depends on the oil price as well as the end of fuel deliveries. The cost per kWh of heat calculator shows the comparison for your own tariff.
The step that settles it
The answer for a particular home comes from a room-by-room heat-loss calculation and a system design: how much heat each room needs on a cold day, what size heat pump that implies, which radiators can deliver it at the planned water temperature, and where the cylinder and outdoor unit go. Ask for that in writing before deciding.
Questions people worry about that rarely rule a home out
- Age. The trial's conclusion covered all the property types it tested; age changes the design, not the answer.
- Microbore pipes. Narrow heating pipes can limit flow, and may mean some pipework is replaced; a design checks it.
- Small gardens or yards. An air source unit needs a modest footprint and air flow around it, not a large garden.
- Cold climates. Heat pumps are widely used in countries far colder than the UK; design for the coldest days handles it.
If the design shows that a heat pump alone would need more work than you are ready for, the hybrid guide describes the halfway option, and its trade-offs.
Keep the design. It is the record of what the system was meant to achieve, and it is the first thing to look at if the home is ever too cold or the bills higher than expected.
Once you know the house can take one, types of heat pump helps narrow the design, air source against ground source weighs the two main options, and the running costs estimator gives a first estimate of what it would cost to run.