Heat Pump vs Gas Boiler — which actually makes sense for your home?

If you’re replacing or upgrading your heating, you’ve probably heard very different opinions about heat pumps and gas boilers.

This page compares them side by side, focusing on costs, disruption, savings, and suitability — not sales claims.

No quotes. No signup. Just the trade-offs.


The short answer

A heat pump is usually better if:

  • your home is already well insulated

  • you plan to stay in the property long-term

  • you’re comfortable with higher upfront cost

A gas boiler is usually better if:

  • upfront cost matters most

  • insulation upgrades aren’t planned

  • you want the simplest replacement

Many households fall somewhere in between — which is why the details matter.


Heat pump vs gas boiler — side by side

CategoryHeat PumpGas Boiler
Upfront costHigh (£7,000–£14,000+)Lower (£2,000–£3,500)
Running costLow–mediumMedium–high
Typical savingsDepends heavily on insulationLimited
Installation timeSeveral days1–2 days
DisruptionModerateLow
NoiseLow hum (external unit)Very low
Space neededOutdoor + indoor spaceIndoor only
Works best whenHome is well insulatedInsulation is limited
Long-term outlookImprovingDeclining
Carbon impactLowHigher

Costs and savings are shown as ranges because homes and usage vary.


Costs, savings, and payback (realistic ranges)

Heat pumps cost more upfront, but can reduce running costs over time — if the home is suitable.

Savings depend on:

  • insulation quality

  • radiator size

  • electricity and gas prices

  • how the system is used

Because of this, payback is best understood as a range, not a guarantee.

Gas boilers are cheaper to install and familiar to most households, but running costs are more exposed to fuel price changes over time.


What installation is actually like

Heat pumps

  • Installation usually takes several days

  • An outdoor unit is required

  • Some homes need larger radiators

  • Space and planning matter

Gas boilers

  • Often replaced within 1–2 days

  • Minimal changes to the home

  • Familiar controls and maintenance

Disruption, not technology, is often the deciding factor.


Why many households decide not to switch (yet)

It’s common to pause or delay because:

  • the upfront cost feels too high

  • savings aren’t certain enough

  • insulation upgrades come first

  • the disruption feels daunting

Waiting can be a reasonable decision.


So which is “better”?

There isn’t a single right answer.

  • Heat pumps make sense when the home is ready for them

  • Gas boilers make sense when cost or disruption is the priority

Understanding that trade-off is more useful than chasing the “best” option.


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