Heat pumps vs gas boilers: Which is better?

✔ The government wants to phase out 80% of gas boilers by 2035

✔ Using a heat pump can reduce your carbon footprint by 44%

✔ The government is offering grants of £7,500 for heat pump installations

The government wants to phase out 80% of gas boilers by 2035. It’s encouraging more homeowners to invest in this greener alternatives, despite the high upfront prices of heat pumps.

This might have you wondering if it’s still a good idea to buy a new gas boiler, or whether you should switch to a heat pump now.

In this article, we’ll break down everything you need to know about gas boilers and heat pumps, comparing costs, maintenance, environmental impact, efficiency, and what type of homes each one is suitable for.

Want to find out exactly how much a heat pump could cost you? Just fill in our short form, and we’ll put you in touch with expert heat pump installers, who can provide tailored quotes.

Should you have a heat pump or a gas boiler?

If you want to reduce your carbon footprint, and you don’t mind paying higher upfront costs, it’s worth getting a heat pump over a new gas boiler.

Plus, getting a heat pump now means you help the government achieve it’s 80% phase out of gas boilers by 2035.

However, you should bear in mind that heat pumps are more expensive to run than gas boilers, since electricity costs three times more than gas. But they are also much better for the environment.

If you want to keep costs down, and your home isn’t well suited to a heat pump – though they work well for the great majority of UK properties – then a gas boiler might be a better option for you.

You’ll want to make sure you get a model that will last a long time, in case the government decides to fully ban new gas boilers at some point.

If you can’t get a heat pump but still want to go green, there are other options you can look into, such as biomass boilers or infrared panels.

Heat pump vs gas boiler: price

Heat pumps are more expensive than gas boilers, which might put some homeowners off them. But how much more expensive are we talking?

A new gas boiler can cost you as little as £1,000 for a basic model, and typically cost £4,000 – covering both the upfront cost and installation.

Heat pumps on the other hand cost significantly more. Buying and installing an air source heat pump will cost £7,000 to £13,000, on average.

Ground source heat pumps are even more expensive. If you get a horizontal installation, you’ll typically pay £24,000, while a vertical installation costs £49,000 on average.

Because of how much heat pumps cost, many people aren’t able to afford them. But with the government’s Boiler Upgrade Scheme, homeowners can cut £7,500 off the price of an air or ground source heat pump.

Heat pumps therefore typically now cost less than gas boilers. But you’ll also need to consider the price of any additional work, such as installation or radiator replacements.

Heat pump vs gas boiler: running costs

Heat pumps are more expensive to run than gas boilers because they use electricity, which is currently four times more expensive than gas.

But heat pumps might not be as expensive to run as you’d think. Since heat pumps are around three times more efficient than gas boilers, they use much less energy to heat the property.

The average UK home uses 11,500 kilowatt hours (kWh) of gas every year, according to Ofgem. With this energy usage in mind, a gas boiler typically costs £694 per year to run, and an air source heat pump costs £1,097 per year.

So even though heat pumps cost slightly more to run than gas boilers, the difference isn’t that big because of how efficient heat pumps are.

And if you pair your heat pump with solar panels, you can lower the running costs of your heat pump by powering it with the free electricity generated by your panels.

You can learn more about heat pump efficiency in our helpful guide.

Heat pump running costs

A ground source heat pump’s running costs for a three-bedroom household will typically come to around £939 per year.

The average air source heat pump will cost about the same, though this can vary significantly, depending on where you live in the UK.

Heat pump vs gas boiler: suitability

Unfortunately, heat pumps aren’t suitable for all types of homes – especially ones that have poor insulation or regular-sized radiators.

Why are these properties unsuitable? It mainly comes down to the fact that heat pumps produce warmth at lower levels than gas boilers, which means you’ll need larger radiators and good insulation to maintain the same levels of heat that a gas boiler would produce.

To make your home suitable for a heat pump, it’s worth installing wall and loft insulation, and investing in radiators that are 2.5 times larger than average units. But this will add to your overall costs.

For example, home insulation costs between £1,400 and £10,000, and replacing radiators can cost £250 to £500 per radiator.

However, some people won’t be able to make their properties suitable for heat pumps – namely people living in listed buildings. This is because homeowners are unable to make changes to a listed building’s appearance, which might rule out having heat pumps in the property.

Another reason why listed properties might not be suitable for a heat pump is that it will be challenging to install the necessary pipework without damaging or changing the building.

If you don’t have much space outside of your property, or you live in a high-rise flat, finding somewhere to put the heat pump’s external unit can also be a challenge.

For ground source heat pumps, you need to have enough space in your garden to house the boreholes that absorb heat from the ground, which usually need to be between 75-200 metres deep.

Gas boilers, on the other hand, have very little limitations. In fact, the only homes that aren’t suitable for gas boilers are ones that aren’t connected to a gas line.

As you can see, there are more obstacles to installing a heat pump over a gas boiler, because most UK homes haven’t been built with this system in mind.

Heat pump vs gas boiler: maintenance

Heat pumps generally require less maintenance than gas boilers. But different types of heat pumps require different maintenance checks.

Air source heat pumps need to be serviced by a heat pump engineer every two to three years – though some warranties require annual checkups. As for day-to-day maintenance, users should regularly check for any debris in the outside unit to keep things running smoothly.

Ground source heat pumps also require very little maintenance, especially since most of their infrastructure is underground, meaning it’s less susceptible to weathering. But again, some warranties require annual checkups.

Maintenance checks cost around £150 for heat pumps, but can be cheaper depending on your installer.

However, it’s also worth noting that there’s a shortage of qualified heat pump installers in the UK – with only a little under 4,000, compared to 100,000 gas safe engineers, according to the MCS. So although heat pump maintenance is relatively simple, finding an installer to conduct regular checks might be challenging.

Gas boilers, on the other hand, usually need to be checked once a year, which will cost between £50 and £100. Day-to-day, you should make sure your boiler is well ventilated – don’t crowd items around it – and keep an eye out for any burgeoning issues, such as leaks, or low/high pressure.

Heat pump vs gas boiler: environmental impact

In terms of environmental impact, heat pumps are the clear winner.

According to our calculations, heat pumps reduce your annual carbon footprint by around 44% compared to a gas boiler.

Heat pumps run on electricity, which releases fewer emissions than gas, since just under 43% of UK electricity comes from renewable sources.

Gas boilers, on the other hand, are powered by natural gas – a fossil fuel that’s responsible for around 75% of global emissions.

Heat pumps are also around three times more energy efficient than gas boilers, which means they use less energy whilst they operate. And consuming less energy on heating will lead to fewer emissions, which is better for the environment.

Heat pump vs gas boiler: efficiency

Heat pumps are much more efficient than gas boilers. Most heat pumps have an efficiency rating of 300%, whereas most new gas boilers are only about 90% efficient.

This means heat pumps can produce three units of energy for every one unit of electricity they consume – in other words, they use much less electricity to heat your home.

To produce the average 12,000 kWh of electricity needed to heat a home, a heat pump only needs to use around 4,000 kWh of electricity. A gas boiler, on the other hand, would use around 13,200 kWh.

It’s important to factor in efficiency when choosing a heating system – the more efficient your system is, the less energy it will use and the lower your energy bills will be.

Heat pump vs gas boiler: the verdict

If you want to lower your carbon footprint, and you can afford the higher upfront costs, and the higher running costs, you should consider getting a heat pump.

But before you make the swap, you need to make sure your home is suitable for a heat pump – or that you can make it suitable by improving its insulation.

If cost is a big factor for you, or you can’t install a heat pump – if you live in a listed building, for example – a gas boiler might be a better option.

And remember, gas boilers and heat pumps aren’t the only options on the market. You can always look into other low-carbon heating methods, such as infrared heating panels, or electric boilers.

Can a heat pump and a gas boiler be combined?

Yes, some installers offer hybrid heating systems that combine air source heat pumps with gas boilers.

This can be a solution for people who live in properties that are unsuitable for heat pumps but want to reduce their carbon footprint without paying for a complete retrofit.

In hybrid systems, the air source heat pump produces around 80% of the warmth for your home, and the gas boiler provides supplemental heating. This is usually necessary during the coldest months of the year, or for hot water.

The main issue with a gas boiler and heat pump combination is that, past 2035, you won’t be able to replace the gas boiler portion of your system with a new one. At this point, a homeowner would have to invest in a retrofit so that they no longer need a gas boiler in the system.

Some installers, such as Worcester-Bosch, note that their hybrid systems could combine hydrogen boilers with heat pumps in the future, instead of gas boilers.

Overall, if you’re ready to invest in a heat pump, it’s a good idea to invest in better insulation along with it, instead of relying on a gas boiler.

Next steps

Investing in a heat pump instead of a gas boiler is a great way to reduce your home’s carbon emissions.

Of course, not everyone can – or wants to – pay the higher upfront costs of a heat pump, not to mention the costs of insulation measures and radiator replacements.

But the technology around heat pumps, and other types of low-carbon heating, is evolving rapidly. This means these gas boiler alternatives probably won’t be as expensive in the future.

If you’ve decided a heat pump is the better option for you, and you want to know how much it would cost, fill in our short quote form. Just put in a few details, and we’ll pass them on to expert heat pump installers, who’ll contact you with their best prices.

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