Heat Pump Cost for a 4-Bedroom House: Full 2026 Breakdown

The most reliable price data comes from installations paid for through the Boiler Upgrade Scheme. Every one has its installed cost recorded on its MCS certificate, and the government publishes the median by heat pump size, including the system, labour and VAT, before the grant. These are the costs installers recorded, not quotes. For the sizes a 4-bed house needs, the 2025/26 figures for England and Wales were:

A typical 4-bed detached house needs about 12 kW on our heat model, which places it between the 10 to 12 kW and 12 to 14 kW medians: about £14,700, with the middle half of installations at £12,500 to £18,000. A 4-bed semi, at 12.5 kW, comes out at £15,000 with a range of £13,000 to £18,000. Across all sizes, the middle half of air source jobs in April to June 2026 cost £11,128 to £15,627, and a 4-bed sits in the upper half of that. It needs a bigger heat pump than a terrace or a semi, it has more radiators to check, and installers spend longer on the design, because a larger house has more rooms to survey and more pipework to trace. That is why the realistic range for a 4-bed is £12,500 to £18,000 before the grant, with well insulated homes at the bottom and older, larger or poorly insulated ones at the top. Use our heat pump calculator for an estimate for your own house type, insulation and heating fuel.

The recorded job cost already includes the heat pump, the cylinder and the labour, so it is the right number to budget from. What moves a 4-bed quote outside the range is mostly the radiators: a house that keeps most of its radiators lands near the bottom, and one that needs most of them replaced, or its microbore pipework renewed, can go above the top. Ask every installer for an itemised quote that lists each radiator they intend to change and says whether that work is in the price.

Not every 4-bed house is detached. A 4-bed semi shares one wall, so you might expect it to need less heat. In the measured consumption data it does not: a 4-bed semi uses slightly more heat a year than a 4-bed detached, 13,770 kWh against 13,140 kWh at average insulation, because a house with four bedrooms and only one shared wall is usually a large semi. It therefore needs a heat pump of the same size or slightly bigger, and costs about the same to install. Do not budget on the semi being cheaper.

At 13,770 kWh of heat demand, a 4-bed semi costs £1,219 a year on gas, £1,304 on a heat pump with a standard tariff, and £926 on a heat pump tariff at the October to December 2026 price cap. The detached figures are in the running costs section below. For the full picture on a smaller semi, read our 3-bed semi heat pump cost guide.

A typical 4-bed detached house needs a heat pump of about 12 kW on our model, and the exact size depends on how well the house is insulated. For comparison, the median air source heat pump fitted under the scheme in April to June 2026 was 8 kW, and a quarter were 10.8 kW or larger, so a 4-bed is at the big end of what installers fit.

Your MCS installer must carry out a room-by-room heat loss calculation before quoting. It works out how much heat each room loses on a cold design day and sizes the unit to cover the total and your hot water with a small margin. Our model's sizes are a guide to the band you will be quoted in, not a substitute for that survey. Oversizing is not a safe default. A unit that is too big costs more to buy and switches on and off more often in mild weather, so treat a quote with no heat loss calculation behind it as a warning sign.

At 10 to 16 kW every major manufacturer has a unit, and some have a high temperature range for houses that keep smaller radiators. The table shows models you are likely to be quoted for a 4-bed house, with specifications from each manufacturer's own pages.

Outputs are the ratings in each range that cover a 4-bed house. Your heat loss calculation decides which one you need.

Brand matters less than design. Ask for a design flow temperature of 50°C or lower, the seasonal performance the installer expects at that temperature in the quote, and an MCS 020(a) sound calculation for the outdoor unit position. R290 units such as the aroTHERM plus can run hotter, which sometimes means fewer radiator changes in an older house, while the Daikin H HT and Samsung HT Quiet reach 70°C on R32. A well designed system from any of these manufacturers will outperform a poorly designed one from the best of them, and the measured spread proves it: in the government's Electrification of Heat trial, the middle half of heat pumps delivered between 2.55 and 3.05 units of heat per unit of electricity over a year. Our heat pump noise guide explains what the noise limits mean for where the outdoor unit can go.

A heat pump runs the heating at a lower water temperature than a gas boiler, so each radiator has to be larger to deliver the same heat. A 4-bed house typically has 10 to 14 radiators, and 4 to 7 of them need upsizing, usually the living room, the hall and landing and the largest bedrooms. Our radiator sizing guide explains how installers decide which ones to change.

You also need a hot water cylinder, and the recorded job costs above include one. A family of four or five needs a larger cylinder than a couple, and the installer sizes it from your household's hot water use. If you currently have a combi boiler there is no cylinder, so you need a cupboard or utility space for one; the Energy Saving Trust says a cylinder can usually fit in any cupboard at least 80cm by 80cm. If you already have a system boiler with a cylinder, it will usually need replacing anyway, because heat pump cylinders have a larger coil to work at lower temperatures.

The common budget breaker is microbore pipework, the 8mm or 10mm pipes fitted in many homes from the 1970s onwards. It restricts flow at heat pump temperatures and often needs replacing with 15mm or 22mm pipe, and on a big house the runs are long. Ask the installer to check the pipe sizes during the survey rather than discovering the problem on installation day.

These figures use the Ofgem price cap for 1 October to 31 December 2026: electricity 26.32p per kWh and gas 7.97p per kWh. Gas rose about 9% at this cap change. Electricity barely moved because the government removed VAT from electricity bills from 1 October 2026 to 31 March 2027, so when 5% VAT returns every heat pump figure below rises by about 5%.

The tariff makes or breaks the economics. On a heat pump tariff you save £280 a year against gas at today's prices, or about £236 once VAT returns to electricity. On a standard tariff the heat pump costs £80 a year more than gas, or about £142 with VAT. Disconnecting your gas supply saves a further £108 a year in gas standing charge. Read our running costs guide for the full comparison, our tariff guide for how to get an effective rate near 18.7p, and our electric boiler vs heat pump guide if you heat with electricity today.

Insulation moves these numbers as much as the tariff does. A well insulated 4-bed detached with 11,169 kWh of heat demand costs £989 a year on gas, £964 on a heat pump with a standard tariff and £685 on a heat pump tariff. Better insulation also lifts the seasonal efficiency, so at that level the heat pump edges ahead of gas even on a standard tariff, and the saving on a heat pump tariff rises to £304 a year. Against oil, the heat pump saves £863 a year on a heat pump tariff and £503 on standard electricity, with heating oil at 11.3p per kWh, the BoilerJuice UK average of 116.20p a litre on 25 September 2026. Oil prices move, so the £1,747 oil bill in the table is today's figure rather than a fixed one.

The Boiler Upgrade Scheme pays £7,500 towards an air source or ground source heat pump in England and Wales. Until 31 March 2027, a home heated by oil or LPG that has no mains gas connection gets an extra £1,500, making £9,000. Your MCS certified installer applies for the grant and it comes off the invoice, so you never handle the money. Regulations in force from 28 April 2026 extended the scheme to 2030 and removed the need for a valid EPC, although your installer records one if the home has it, and installations carry 0% VAT until 31 March 2027. There is no limit on the value of the house, and the 45 kW cap on a single system is far above anything a 4-bed needs, so a 4-bed detached qualifies exactly as a flat does, provided you own it and the heat pump replaces fossil fuel heating such as gas, oil, LPG or electric heating. Hybrid systems that keep a boiler do not qualify. Read our BUS grant guide for the full eligibility rules and our grant checker for everything else you might qualify for.

The government puts the average cost of a new gas boiler at about £3,500 including VAT, and our boiler vs heat pump comparison scales that by home size to about £3,800 for four bedrooms. Against that, a typical 4-bed detached heat pump job costs £1,200 to £6,700 more after the £7,500 grant, plus any radiator work that is not in the quote. At £280 a year saving on a heat pump tariff, that is a payback of about 4 to 24 years, or 5 to 28 years once VAT returns to electricity, and on a standard electricity tariff there is no saving to pay anything back at all. On mains gas, then, a 4-bed detached is a weak case on running cost alone: at the median price the extra takes about 12 years to earn back even on a heat pump tariff, and it pays back quickly only if you land near the low end of the cost range. Off the gas grid the case is much stronger. Against oil the saving is £863 a year with oil at 11.3p per kWh, the BoilerJuice UK average on 25 September 2026, although oil prices move, and the £9,000 grant takes the whole job to £3,500 to £9,000 if you claim before 31 March 2027, with no oil tank to maintain afterwards. Run the numbers for your own house with our boiler vs heat pump comparison, and read heat pump vs new boiler for the 15-year view.

For most 4-bed homes air source is the practical choice. Ground source usually runs more efficiently, because the ground stays warmer than winter air, but the government's heat pump trial measured too few ground source systems to give a reliable figure, so we do not price the running cost difference. What is certain is the upfront gap: the median ground source job under the scheme cost £27,232, against £14,700 for a typical 4-bed air source job, and it needs a drilling rig or a large trench in the garden. It makes sense for a detached house with plenty of land and a long ownership horizon. Read our costs by house type guide for the full comparison across property types.

Get three quotes from MCS certified installers, and compare them on the design rather than the headline price. Each quote should include:

• A room-by-room heat loss calculation with the design outdoor temperature stated.
• The design flow temperature, ideally 50°C or lower, and the seasonal performance the installer expects at that temperature.
• A radiator schedule listing every emitter, which ones change, their new sizes, and whether that work is in the price.
• The cylinder size and where it will go.
• An MCS 020(a) sound calculation for the outdoor unit position, showing it meets the 37 dB limit at the nearest neighbour's window.
• The warranty on the unit and on the installation, and who you call when something fails.
• Confirmation that the installer will apply for the Boiler Upgrade Scheme at the £7,500 or £9,000 rate and deduct it from the invoice.

Installation usually takes several days for the heat pump and cylinder, and longer if most radiators are being swapped. Check the planning permission rules before you sign. Most 4-bed houses in England are covered by permitted development, except listed buildings and, in conservation areas, units on a wall or roof facing a road. Find installers through the MCS installer search.

Installed costs from the DESNZ Boiler Upgrade Scheme statistics, August 2026, Table A1.3A (median cost by heat pump size, 2025/26, 30,590 air source installations) and Table Q1.1A (April to June 2026 quartiles). Costs are self-reported by MCS installers and include the system, labour and VAT, before the grant. Heat pump efficiency from the Electrification of Heat trial report (Energy Systems Catapult for DESNZ, December 2024, Table 1.2). Heat demand from our heat model, built on the DESNZ National Energy Efficiency Data-Framework (NEED) 2026. Measured insulation savings from NEED impact of measures 2026. Energy prices from the Ofgem price cap for October to December 2026. Heating oil price from BoilerJuice: the UK average of 116.20p a litre including VAT on 25 September 2026, converted at 10.294 kWh a litre using the DESNZ greenhouse gas conversion factors 2026 (gross calorific value). Heat pump tariff: Cosy Octopus at October 2026 rates with 60% of heating in the cheap hours and 10% in the 4pm to 7pm peak, as costed in our tariff guide. New gas boiler cost from the DESNZ Boiler Upgrade Scheme 2026 to 2030 summary business case, footnote 8, scaled by home size as in our boiler vs heat pump comparison. Grant rules from GOV.UK and The Boiler Upgrade Scheme (England and Wales) (Amendment) Regulations 2026. VAT from HMRC VAT Notice 708/6. Planning rules from the permitted development rules, Class G and MCS 020(a). Insulation costs from the Energy Saving Trust. Full method on our methodology and data sources pages. Heat pump specifications from the manufacturers: Vaillant aroTHERM plus, Mitsubishi Electric Ecodan, Daikin Altherma 3 H HT and Samsung EHS Mono HT Quiet.