How do I know if a heat pump is right for my home? 7 questions to ask yourself or a professional

While the UK government might have scrapped plans to ban selling new gas boilers by 2035, the number of homeowners swapping their boilers for heat pumps is still on the rise thanks to the energy-bill slashing effect they can have on a home.

That said, for all their benefits, heat pumps might not always be the best solution for every household and, let's not forget that even when taking advantage of the government's boiler upgrade scheme, the cost of a heat pump is still pretty significant. I am currently mulling over the idea of installing one myself as part of the alterations we are planning on making to our home but am hesitant due to the fact that our old Edwardian cottage is pretty energy inefficient.

If, like me, you are still on the fence about whether a heat pump is right for your home, I am here to help. I asked some leading experts in the field to explain the questions you need to be asking before making this important decision – here's what they had to say.

Is a heat pump right for you?

This is a question I have been asking myself lately. We currently have an electric boiler for our heating and hot water as we live rurally with no gas connection. Our house is also pretty poorly insulated and draughty – in short, a lot of heat loss goes on here. For this reason, I kind of assumed a heat pump would be a bit of a waste – but is this really the case? Martyn Fowler, founder of Elite Renewables, says not.

'The first thing I’d say is that almost any home can have a heat pump if it’s designed properly. We’ve installed systems in everything from large country homes with huge footprints to compact Victorian terraces,' says Martyn. 'The difference is always in the design not the property type. The real question is, has your home been properly assessed?'

Given that my home has not, in fact, been assessed, I was really keen to find out what questions I should be asking before making a decision on this.

Martyn Fowler

Founder of Elite Renewables, Martyn Fowler is one of the UK's leading renewable technology experts, working with heat pumps for the last 2 decades. His passion for decarbonisation matched with a deep technical experience of the technology make him one of the industry's go-to experts for all things renewable.

1. How well insulated is my home?

First up, it is important to look at how your home is currently performing in terms energy efficiency – and particularly at how well insulated it is.

'This is very important because heat pumps, especially air source heat pumps, work best when they're making heat at slightly lower temperatures, like 35°C to 55°C, for longer amounts of time,' explains Sean Hogan, founder of Aventus Eco. 'That lower-temperature heat will leave your home too fast if it isn't well sealed and has a lot of leaks, making it hard for the heat pump to keep the house warm. Your running costs will go up because of that battle, and you won't be as comfy either. That's why we always say: put up insulation first, then fit the heat pump.

'You should think about your loft insulation, those empty walls, your floor, and even draught proofing,' continues Sean. 'If you put money into good insulation up front, your home will need a lot less heat. This lets a smaller, more efficient heat pump work at its best, which keeps the costs of running it low. Putting in good insulation first is often a better use of money than trying to make up for it with a larger heat pump.'

'It’s a myth that your home has to be perfectly insulated for a heat pump to work. But if your home loses heat easily, you’ll need a bigger, more expensive heat pump, which can be louder, less comfortable and may not save you that much money,' points out Becky Lane, CEO of Furbnow. 'Heat pumps work best in homes with good insulation, usually with an EPC rating of a strong C or above.'

Sean Hogan

Sean Hogan is founder of Aventus Eco, a renewable energy and heating company based in Scotland, dedicated to helping homeowners reduce energy bills, cut carbon emissions, and future-proof their properties. They specialise in the design and installation of air source heat pumps, solar PV systems, and battery storage solutions.

Becky Lane

With more than 15 years’ experience in home energy, Becky has led major programmes that changed how the UK approaches improving its homes. As a qualified Retrofit Coordinator, she brings both technical insight and hands-on experience from working with households, councils and industry.

2. What heat emitters do I have at the moment?

Next up you need to assess the way you are currently heating your home and think about how your heat emitters – radiators, underfloor heating and so on – are going to get on with a heat pump.

'Because heat pumps run cooler, you need more surface area to get the same heat output,' explains Jack Allen, MD and founder at Building Energy Experts. 'Are your current radiators large enough? You may need to swap single-panel radiators for double or triple panels (K2 or K3 types) or install underfloor heating.'

'Your radiators need to be able to put out enough heat at those lower temperatures that heat pumps work at for them to really work,' picks up Sean Hogan. 'This usually means that your old radiators will need to be bigger than they would for a gas boiler, or you might need to get new, high-output models.

'Underfloor heating works well with low flow rates, which makes it a brilliant choice for a heat pump system,' continues Sean. 'This is a useful point because you may need to replace some or all of your radiators, which will naturally raise the cost of the work as a whole. A good contractor will always do a full room-by-room heat loss estimate to make sure that your new or old radiators are the right size for your heat pump system. We've found that existing, bigger radiators can work really well in some older UK homes.'

Jack Allen

Jack Allen has 14 years experience in sustainability in the built environment, working on planning sustainability through to post completion testing and certification as well as retrofit assessments and home energy surveys. He set up Building Energy Experts to bridge the gap between desk-based energy modelling and the actual energy performance of buildings. The focus on bridging this performance gap drives the company’s approach to solving clients’ challenges.

3. Do I have enough space for a heat pump?

This is a really important question to ask – heat pumps take up space and if you don't have anywhere to put one you are going to struggle. A great big heat pump stuck to the outside of a house rarely does anything to add kerb appeal and this has been something that has put me off the idea a little, although there are ways of hiding a heat pump.

'Air source heat pumps need a box outside that looks a bit like an air conditioner,' explains Sean Hogan. 'This unit needs to be put in a stable place with good airflow, preferably away from bedrooms to keep noise to a minimum (though modern units are very quiet these days), and there needs to be enough room for installation and future upkeep too.'

It isn't just outside of your house that you need to consider space requirements for either.

'Inside your home, you’ll usually need room for a hot water cylinder – about the size of a large fridge-freezer – often in an airing cupboard or utility room,' advises Becky Lane. 'You’ll also need pipework running from the heat pump to that cylinder, which can mean lifting floors or working behind kitchen units. In many Victorian and Edwardian homes, that can be quite disruptive for what might only be small savings. Get a home energy plan, so you can understand which steps and renovations are needed before you can actually turn on your heat pump.'

4. Will a heat pump save me money on energy bills?

For many people, the biggest factor that influences their decision when it comes to installing a heat pump is cost.

'Installation can range from around £8,000 to £15,000 depending on the property and what upgrades are needed,' says Martyn Fowler. 'The Boiler Upgrade Scheme currently provides £7,500 towards it. I always encourage homeowners to think long term. A properly installed heat pump gives you stable running costs and protection against future gas price volatility.'

'While the Boiler Upgrade Scheme can save you money, homeowners still need to think carefully about total costs. If your home isn’t well insulated you might need an oversized heat pump and also new radiators, a hot water cylinder and extensive pipework. That can mean paying £10,000 to £15,000 yourself,' points out Becky Lane. 'You need to think, over time, will the money you save on your energy bills cover the cost of installing a heat pump? In a poorly insulated home, it might not.

'With good insulation, space outside, and room indoors for a cylinder, you could save close to £400 a year, especially if you’re on a tariff with cheaper off-peak electricity,' adds Becky. 'The key is knowing whether your home is heat pump ready.'

5. Will I be happy with a lower, slower heat source?

It is important to be aware that living with a heat pump is very different from living with a boiler – and you need to think about whether you are ready for the shift.

'Gas boilers are reactive – you turn them on, and the house gets hot quickly. Heat pumps are 'steady-state' meaning they work best when left running in the background to maintain a constant temperature,' explains Jack Allen. 'You need to ask yourself, is my lifestyle suited to constant heating, or do I need instant heat?'

In short, if you love the fact that your gas boiler allows you to flick a switch and enjoy instant heat from your radiators, it may take time to adjust to the slower, steadier warmth that a heat pump offers, although if you already have underfloor heating, you are likely to be used to this.

6. Is your pipework capable of handling a heat pump?

If you live in an older property or are carrying out the renovation of one, switching from a gas boiler to a heat pump can be more complex and along with insulation upgrades you will also need to consider your current distribution system.

'Do you have 'microbore' pipework? Many UK homes built in the 80s and 90s use these narrow 8mm or 10mm pipes,' explains Jack Allen. 'These can struggle with the higher flow rates a heat pump requires, potentially needing a full re-pipe which significantly increases installation costs.'

According to Martyn Fowler, you often won't know if your pipework is up to scratch until you have had your home properly assessed.

'You need a full heat loss calculation. That tells you how much heat your home actually needs on the coldest day of the year. Once you have that, you size the heat pump correctly and design the distribution system around it,' explains Martyn. 'That might mean upgrading some radiators, improving insulation in key areas, or adjusting pipework. When the system is designed properly, the performance follows.'

7. What are your long-term goals?

And, finally, you really need to think through your reasons for wanting to install a heat pump – basically, what are your expectations?

'It's worth asking yourself: what is my current energy consumption, and what are my long-term goals for energy saving and independence, as well as reducing my carbon footprint?' says Sean Hogan. 'Even though a heat pump may cost more up front than a regular boiler, it will save you a lot of money in the long run compared to fossil fuel heaters. At a time when fossil fuel prices are still very unstable and our power grid is becoming 'greener' this is even more important.

'It makes sense to get a heat pump if you want to become truly energy independent and lower your carbon footprint. You could even combine it with other renewable energy sources like solar PV and battery storage,' continues Sean. 'Figuring out why you're doing this is a big part of weighing the original cost against the long-term financial and environmental rewards.'

FAQs

Where might a heat pump not be a suitable option?

While all the experts agreed that heat pumps were a brilliant option for most types of home, there are cases where installing one just might not be worth it.

'While we are advocates for electrification, we often advise clients against heat pumps in the following scenarios until remedial works are done,' says Jack Allen.

• The 'leaky bucket' home: If you have solid walls with no insulation and single glazing, a heat pump will likely cost more to run than a gas boiler. You are effectively trying to fill a leaky bucket; you need to plug the holes (insulation/airtightness) before you change the tap (the heating system).
• Flats with no outdoor space: If you are in a flat with no outdoor space, finding a compliant location for the external unit can be impossible due to planning permission and noise distance regulations.
• Homes with microbore pipework: As mentioned above, if ripping up floors to replace 10mm piping is too disruptive or expensive, a high-temperature heat pump or a hybrid system might be the only viable option.

'In the end, the best way to know for sure if a heat pump is right for your home is to have an MCS-certified heat pump provider do a skilled, in-depth study and heat loss estimate,' concludes Sean Hogan. 'They can look at the unique features of your home and give you help that fits your needs, so you can make an informed choice.'

If you have come to the conclusion that a heat pump won't suit your home, don't be disheartened – there are many other types of heating systems out there to choose from.