Heat Pump for a Victorian Terrace: Cost and What It Takes in 2026

The median heat pump installation funded by the Boiler Upgrade Scheme cost £12,908 in April to June 2026, with a quarter of jobs under £11,128 and a quarter over £15,627 (DESNZ Boiler Upgrade Scheme statistics, Table Q1.1A). A Victorian terrace sits close to that median rather than at the bottom of the range, because a small house can still be a hard one to heat: a nine-inch solid wall loses more than twice the heat of a filled cavity, the sashes leak air, the floor sits over a ventilated void, high ceilings add to the volume, and the outrigger adds two exposed walls and a cold bathroom at the far end of the pipe run.

Within each row, the pipe run and the cylinder set the price. A cylinder cupboard still in the outrigger bathroom, directly above the unit, is a short job; a cylinder in a front bedroom, 15 metres of pipe away, is not. A four bedroom terrace, an end terrace or a long pipe run sits nearer the top of the range. Use our heat pump calculator for an estimate at your own insulation level and fuel.

Heat pump installations carry 0% VAT until 31 March 2027 (HMRC VAT Notice 708/6). Installed costs from DESNZ Boiler Upgrade Scheme statistics, Tables A1.3A and Q1.1A.

Two things take away the advantage the terrace's size should give it. Radiators: the rooms are tall and the front rooms sit behind the coldest wall, so at a low design temperature many radiators change, while a higher temperature model keeps more of them. Pipework: insulated primaries have to reach the cylinder upstairs, usually up the outside of the outrigger. Suspended timber floors are the one break the house gives you, because lifting boards to run new pipe is quick work where a concrete-floored semi needs it chased in.

A Victorian terrace shares two walls, so on paper it should be cheap to heat. In practice even an unimproved one uses about as much heat as a typical 3-bed semi, 9,790 kWh against 9,900, and costs about the same to fit a heat pump to, because the access is worse and the pipe run longer. The two party walls buy back what the solid brick, the sashes and the bare floor give away.

At the October to December 2026 price cap the band D semi at 9,900 kWh costs £877 a year on gas, £937 on a heat pump with a standard tariff and £666 on a heat pump tariff. A Victorian terrace with the walls insulated as well, at 7,497 kWh (band C), comes in at £664, £647 and £460. Unimproved, the terrace is level with the semi on gas, at £867, but costs £718 on a heat pump tariff, £52 more than the semi, because our model assumes a lower efficiency for a band E house; insulate the walls and it wins.

On our model a three bedroom Victorian terrace needs a 7 to 9 kW heat pump, and where you land depends on what you do to the fabric first. The size for your house comes from a room-by-room heat loss calculation at the design outdoor temperature for your location. The RdSAP 10 assessment method gives a nine-inch solid brick wall a default of 1.7 W/m²K, against 0.7 for a filled cavity (BRE), so the walls are a large share of the loss in a bare terrace. A quote without the calculation was sized by guesswork; our heat pump sizing guide explains how it is done. What comes off the annual demand comes off the peak load too, and in the Boiler Upgrade Scheme data each kilowatt less is worth roughly £250 to £650 off the median installed price. The measures below are in rough order of cost, with the Energy Saving Trust's typical prices and, where it exists, the saving measured in real homes.

• Loft to 270mm: about £750 from nothing or £600 as a top-up from 120mm, fitted. The bare or thin loft in many terraces is the cheapest of the fixes (Energy Saving Trust, May 2026). Homes that had loft insulation fitted or topped up in 2023 used a median 3.2% less gas the following year (DESNZ NEED). See our loft insulation guide and DIY loft guide; on a qualifying benefit, ECO4 may pay for it, provided the work is finished before ECO4 closes on 31 December 2026; the Great British Insulation Scheme closed on 31 March 2026.
• Draught-proof the sashes: around £250 for professional draught-proofing of a whole house's windows and doors. The Energy Saving Trust puts the saving from draught-proofing windows, floors and doors at around £55 a year, and from sealing an unused chimney at around £45 (May 2026). Brush pile in the sash channels and meeting rail and sealed floorboard and skirting gaps do most of it. Our draught-proofing guide has the sash method.
• Insulate the suspended floor: £1,400 to £2,500 for a typical suspended floor. The Energy Saving Trust puts the saving at about £40 a year for a mid-terrace house (May 2026). Mineral wool between the joists from a cellar or crawl space is the least disruptive route; otherwise the boards come up, which pairs well with new pipework. See our underfloor insulation guide and keep the air bricks clear.
• Double or secondary glazing: around £4,800 for A-rated windows on a semi. The Energy Saving Trust puts the saving from replacing single glazing at about £85 a year (May 2026), so do it last unless the sashes are rotten. Secondary glazing keeps the originals, which matters in a conservation area.
• Then internal wall insulation on the coldest rooms: around £12,000 for a whole typical three bedroom semi, less for a smaller terrace or a few rooms. Homes that had solid wall insulation in 2023 used a median 17.3% less gas the following year, the largest measured saving of any single measure (Energy Saving Trust, June 2026; DESNZ NEED). Start with the front room, the front bedroom and the outrigger. On our model it takes a terrace from band D to band C, 8,820 kWh to 7,497 kWh, and from an 8 kW unit to 7 kW. Our solid wall insulation guide has the costs; done badly it traps damp in the brick, so read our condensation guide first.

Measured savings are lower than modelled ones, partly because many homes were under-heated before and take some of the gain as warmth, so treat them as what homes like yours typically saw rather than the most you could save. The worked example in this guide is the band E terrace at 9,790 kWh, an unimproved or lightly improved solid wall house, which needs a 9 kW unit on our model and is the terrace many readers own. Model yours with the insulation calculator.

The models that suit a Victorian terrace reach higher flow temperatures, so the installer can design at 55°C and keep more of the radiators you have. Outputs and maximum flow temperatures were checked against the manufacturer pages and datasheets in the data sources.

At this size the brands are close and the design decides the result. A 75°C ceiling is headroom, not a running temperature: a unit that can reach 75°C is working comfortably at 55°C on the coldest day. Ask for the seasonal performance at the design flow temperature in writing. Solid walls do not doom a heat pump: in the Electrification of Heat trial the median whole system figure for pre-1919 homes was 2.90, against 2.78 across all 428 homes, and the trial found no significant difference by the age of the house where an installer had judged it suitable. Ask for an MCS 020(a) sound calculation for the exact spot in the yard too. Our heat pump noise guide explains the decibel figures.

A heat pump runs at a lower water temperature than a boiler, so radiators need more surface to give out the same heat, and the lower the design flow temperature the more surface they need. Victorian terraces are better placed than most, because radiators fitted in the 1970s and 1980s were often generous for the walls and the rooms have wall space for tall column radiators. At a higher design temperature expect a few to change, usually the front room, front bedroom and outrigger bathroom, and more at a lower one; the work is part of the installed price rather than an extra. Our radiator sizing guide explains how installers decide.

Cast iron radiators can stay if they are big enough, and many are: they hold a lot of water and give off heat slowly, which suits a heat pump's steady low temperature. The installer works out the output at the design flow temperature from the section count and height, and if it falls short a second one in the same style is the usual answer. Where a radiator does change, a steel column radiator gives the period look for less than cast iron.

You also need a hot water cylinder sized to the household's hot water use; the Energy Saving Trust says it will usually fit a cupboard of at least 80 cm by 80 cm. Terraces that never had a combi often still have the cylinder cupboard in the outrigger bathroom, the best spot in the house, directly above the kitchen and one short run from the unit. Otherwise it goes in a bedroom cupboard, the alcove beside a chimney breast where a slimline cylinder fits, or the box room. Pipework is where terrace quotes vary most: the insulated primaries can run 10 to 20 metres, cheapest up the outside of the outrigger in a boxed duct, and narrow 8mm or 10mm microbore may need replacing, though Octopus says its Cosy heat pumps work with microbore of 10mm or larger. Ask the installer to lift a board and check pipe sizes at the survey.

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, a gas boiler at 90% efficiency, and a heat pump at the seasonal efficiency our model uses for each EPC band: 2.55 for the band E worked example, the lower quartile measured in the Electrification of Heat trial, rising to 2.78 at band D and 3.05 at band C. That is a cautious assumption for this house, because the same trial found pre-1919 homes did as well as newer ones. Electricity carries no VAT from October 2026 to March 2027 while gas includes 5%, so if 5% VAT returns to electricity in April 2027 at the same underlying price, the heat pump figures rise by 5%, which would cut the band E terrace's heat pump tariff saving against gas to £113 a year.

Insulating cuts both bills and widens the heat pump's advantage at the same time, because a better fabric lets the installer design at a lower flow temperature. At band D the terrace needs 8,820 kWh at an efficiency of 2.78: £781 a year on gas, £835 on a standard tariff and £593 on a heat pump tariff, a £188 saving. Insulate the walls too, to band C, and it is 7,497 kWh at 3.05: £664 on gas, £647 on a standard tariff and £460 on a heat pump tariff, a £204 saving, and the point at which the heat pump beats gas without a special tariff, by £17 a year. As the house stands, the £149 saving is £2,980 over 20 years at today's prices, plus the £108 a year gas standing charge if you cap the supply. Read our running costs guide and our tariff guide for how Cosy Octopus works out at about 18.7p per kWh with most heating in the cheap hours.

The Boiler Upgrade Scheme pays £7,500 towards an air source or ground source heat pump in England and Wales. Until March 2027 it pays £9,000 where the home is heated by oil or LPG and has no mains gas connection (GOV.UK). Your MCS-certified installer applies, and since April 2026 the installer must take the grant off the price quoted to you, so the heat pump costs £4,700 to £5,200 at the medians. The scheme runs to 2030 and installations carry 0% VAT until March 2027. You need to own the house and be replacing fossil fuel or electric heating; since April 2026 you no longer need a valid EPC, and a bare loft has not blocked the grant since May 2024, though it should still be the first thing you fix. Read our BUS grant guide for the rules, our grant checker for anything else you qualify for, and our Warm Homes Plan guide for insulation funding. On a qualifying benefit, ECO4 can pay for wall insulation outright until it closes on 31 December 2026, and in England households on a low income can ask their council about the Warm Homes: Local Grant.

Against a new gas boiler, about £3,500 for a three bedroom home according to DESNZ, including VAT, the band E terrace pays £5,200 for the heat pump after the grant, about £1,700 more. At £149 a year on a heat pump tariff that is a payback of about 11 years, inside the 20 years the government assumes a heat pump lasts (Boiler Upgrade Scheme impact assessment, 2022). The margin narrows if 5% VAT returns to electricity in April 2027: the saving falls to about £113 a year and the payback lengthens to about 15 years. A job at the top of the range, £8,000 after the grant, would not pay back within that life; one at the cheap end, £3,500 after the grant, costs no more than the boiler, and that is where a terrace with the cylinder cupboard still in the outrigger bathroom and radiators already generous tends to land. On a standard tariff the band E terrace does not pay back at all on our model, because the heat pump costs £143 a year more to run than the gas boiler. That is the honest position for this house on our cautious assumption. It is a comfort and carbon decision first, and a money decision on a heat pump tariff, or after the walls are insulated, which on our model puts the heat pump £17 a year below gas even on a standard tariff. Run your own figures with our boiler vs heat pump comparison, read heat pump vs new boiler for the 15-year view, and see why an electric boiler costs almost three times as much to run in our electric boiler vs heat pump guide.

With no side access the outdoor unit goes in the rear yard, and the usual spot is the side wall of the outrigger, facing across the yard: a short pipe run to the bathroom above, off the rear wall where the kitchen door and window are, and clear air in front. Avoid the corner where the outrigger meets the main house: under the MCS 020(a) method a unit against two walls and the ground counts as having three reflecting surfaces, which adds 3 dB to the result against one wall. A monobloc outdoor unit can weigh 100 kg or more, and it comes through the front door and out through the kitchen on a stair-climbing trolley; if your street has a rear alley, say so at the survey.

Permitted development in England used to require one metre from every boundary. That rule went in May 2025, and the conditions now are the MCS 020(a) sound calculation, which must show 37 dB or less at one metre from each neighbour's nearest habitable room window or door, a unit of no more than 1.5 cubic metres, only one heat pump on a house that is not detached, and nothing above ground floor level on a wall facing a highway (GPDO Class G; MCS). Wales moved to the same MCS 020(a) test on 1 June 2026 (MCS). With two neighbours whose rear windows are only a few metres away, the calculation has to pass on both sides. At one metre the Grant Aerona 290 range runs from 40 to 46 dB(A) and the Ecodan Ultra Quiet 8.5 kW is 45 dB(A); most terraces pass with the unit in the middle of the outrigger wall, and one forced towards a fence may need a quieter unit or an acoustic enclosure. Tell both neighbours before the survey. Our planning permission guide covers the rules and our noise guide the numbers.

Conservation areas do not stop you: an air source heat pump is still permitted development in a conservation area in England as long as it is not on a wall or roof facing a highway and is no nearer the road than the house, and a rear yard meets both tests. A listed terrace always needs planning permission for a heat pump, because permitted development does not apply anywhere within the grounds of a listed building (Planning Portal), and usually listed building consent for the unit, the pipework and the holes through the wall. Check for an Article 4 direction on your street too.

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

• A room-by-room heat loss calculation using the real solid brick wall figure, not a default cavity figure, with the design outdoor temperature stated.
• The design flow temperature and the seasonal performance expected at it, in writing.
• A radiator schedule listing every emitter, which stay, which change, and their new sizes.
• The cylinder size and location, ideally the outrigger bathroom, and the route and length of the primary pipework.
• An MCS 020(a) sound calculation for the exact spot on the outrigger wall with both neighbours' nearest windows and doors marked, and confirmation of conservation area, Article 4 or listed status.
• The unit and installation warranties, and confirmation that the Boiler Upgrade Scheme grant is already taken off the quoted price.

Installation usually takes longer in a terrace than in a semi, because of the pipe run and the carry-through. Find installers through the MCS installer search, and read our old house guide for the listed building and period detail that applies to every pre-war home.

If the unit sits on a plinth against a wall you share, anti-vibration pads under its feet stop the hum reaching next door's bedroom.

Installed prices from DESNZ Boiler Upgrade Scheme statistics, August 2026 release (Table A1.3A, median cost by capacity, 2025/26; Table Q1.1A, quartiles for April to June 2026). Heat pump efficiency, including results by house age, from the Electrification of Heat Demonstration Project performance report (Energy Systems Catapult for DESNZ, December 2024, Tables 1.2 and 8.9). Heat demand from our heating model, built on the DESNZ National Energy Efficiency Data-Framework and described in our methodology. Measured insulation savings from NEED impact of measures (June 2026). Insulation costs from the Energy Saving Trust (loft, draught-proofing, floor, windows, solid wall). Default wall U-values from the RdSAP 10 specification. Energy prices from the Ofgem price cap for October to December 2026. Heat pump tariff from Cosy Octopus at October 2026 rates, as costed in our tariff guide. New gas boiler cost from the DESNZ Boiler Upgrade Scheme summary business case. Grant rules from GOV.UK, and permitted development conditions from legislation.gov.uk and the Planning Portal. Heat pump outputs and maximum flow temperatures from the manufacturers: Vaillant aroTHERM plus, Daikin Altherma 3 H MT catalogue, Mitsubishi Electric Ecodan R290, Viessmann Vitocal 150-A, Octopus Cosy and the Grant Aerona 290 data sheet.