How Much Does Central Heating Installation Cost in London?
A full central heating installation in London typically costs £4,000–£9,000+ for a standard 3-bedroom home, replacing an existing system with usable pipework. Smaller flats can come in from around £3,000, while larger 4-bedroom-plus properties, or homes needing central heating fitted from scratch, often run to £10,000–£14,000. That range is wide because “central heating installation” covers very different jobs — a straightforward swap onto pipework that already works is a different price entirely from running new pipe through solid floors in a house that’s never had heating at all.
Below is what actually goes into that number, broken down by property size, what’s included, and what tends to push a quote toward the top or bottom of the range — so you can sanity-check any quote you’re given rather than just comparing headline figures.
Central Heating Installation Cost in London, by Property Size
| Property | Typical London cost (existing pipework) | Notes |
|---|---|---|
| 1-bed flat | £3,000–£4,500 | Fewer radiators, shorter pipe runs |
| 2-bed property | £3,500–£5,500 | Combi boiler, 5–7 radiators |
| 3-bed house | £4,000–£9,000 | Combi or system boiler, 8–10 radiators |
| 4-bed+ house | £7,000–£12,000+ | Larger boiler, 10+ radiators, longer runs |
| No existing pipework (any size) | Add roughly £1,000–£3,000+ on top of the above | New pipe runs through floors/walls |
These are guide ranges, not a quote — London costs sit above the national average because of labour rates and, in some properties, more difficult access (period conversions, solid floors, listed buildings). A site visit is the only way to get an accurate number for your specific property, because two 3-bed houses with the same bedroom count can have completely different pipework, wall types, and boiler positions.
What’s Actually Included in a Central Heating Installation?
Short answer: yes, a full central heating installation includes the boiler and the radiators, along with the pipework, controls, and the commissioning work needed to make it all function as one system — not just the parts fitted separately.
A proper quote should cover:
- The boiler itself — sized correctly for the property (a 1–2 bed flat typically needs a 24–27kW combi; a 4-bed-plus house often needs 35–42kW, depending on hot water demand and radiator count).
- Radiators, sized per room based on floor area, insulation, and window area — not a single standard size fitted everywhere.
- Pipework, either reusing existing runs (cheaper) or new runs where none exist or the old pipework isn’t fit for purpose.
- Heating controls — a room thermostat, thermostatic radiator valves (TRVs), and a programmer or smart control, which since 2018’s Boiler Plus regulations are a required part of any new gas boiler installation in England, not an optional extra.
- System flush and inhibitor, to protect new radiators and pipework from the sludge and corrosion that often builds up in an older system.
- Commissioning and certification — gas tightness testing, a completed Benchmark Checklist, and Building Regulations notification to the local authority, exactly as with a standalone boiler installation.
If a quote is noticeably cheaper than others you’ve had, it’s worth checking whether controls, a full flush, or commissioning paperwork have quietly been left out — those aren’t corners worth cutting.
What Determines Your Price
Number of radiators and pipe runs
This is the single biggest cost driver after the boiler itself. A typical 3–4 bedroom house needs around 8–10 radiators; larger homes can need 15–20+. At roughly £150–£400 fitted per radiator depending on size and style (a standard steel panel radiator sits at the lower end; vertical, column, or designer radiators cost considerably more), the radiator count alone can shift a quote by several thousand pounds.
Whether pipework already exists
Reusing existing, usable pipework is always cheaper than running new pipe. If you’re heating a property for the first time — converting from electric storage heaters, or a property that’s genuinely never had gas central heating — expect floors to be lifted in places and an extra £1,000–£3,000+ on top of a like-for-like figure, depending on floor construction and how many rooms need a new feed.
Boiler size and type
A combi boiler is usually the most cost-effective choice for a property without unusually high simultaneous hot water demand. A system boiler with a hot water cylinder costs more to install (the cylinder and its associated pipework add both material and labour) but suits larger households or homes with multiple bathrooms where several taps might run hot water at once.
Property type and access
Solid-floor properties, period conversions with unusual layouts, and flats with restricted access for pipework or a flue all add time and therefore cost. A straightforward semi-detached house with a suspended timber floor is generally the quickest and cheapest to fit.
London labour rates
Labour is consistently the largest single factor in why London quotes run higher than national averages for an identical spec — it isn’t that the parts cost more, it’s that engineer day rates in and around London are higher than in most of the rest of the UK.
Installing Central Heating in a House With No Existing System
Short answer: yes, it’s entirely possible to fit central heating into a property that’s never had it — older conversions, some listed buildings, and homes previously heated by storage heaters or open fires are common examples — but it costs more than replacing an existing system, because every pipe run has to be planned and installed from nothing.
This typically involves:
- Lifting sections of flooring to run pipework between rooms (more disruptive and more labour-intensive in solid-floor properties than suspended timber ones).
- Deciding radiator positions from scratch, rather than reusing existing pipe drops.
- A new flue route, since there’s no existing one to reuse.
- Potentially more extensive electrical work for the boiler and controls.
It’s a bigger job and a bigger disruption than a replacement, which is why it’s worth budgeting toward the higher end of the ranges above and expecting a longer installation window.
How Long Does Central Heating Installation Take?
A straightforward system in a smaller property can be completed in 2–3 days. Larger homes, more radiators, or a from-scratch installation with new pipework can take a week or more. If you’re specifically asking about a boiler swap rather than a full system, we’ve covered installation timeframes for that separately.
Gas Safe, Building Regulations & What a Proper Quote Should Include
Any gas boiler work as part of a central heating installation must legally be carried out by a Gas Safe registered engineer — you can verify any engineer’s registration number directly on the Gas Safe Register website before work starts. Once the boiler is commissioned, your engineer should complete a Benchmark Checklist (required for most manufacturer warranties) and notify the installation to your local authority within 30 days, which triggers your Building Regulations Compliance Certificate — a document worth keeping, since it’s commonly requested by solicitors when a property is sold.
A quote that doesn’t mention any of this, or a price that seems too good to be true for the scope described, is worth questioning before you commit.
Common Mistakes When Comparing Central Heating Quotes
- Comparing headline prices without checking scope. A £4,000 quote and a £6,500 quote for “the same job” often aren’t the same job at all — one may exclude controls, a full flush, or enough radiators for every room.
- Not confirming whether pipework is being reused or replaced. This single factor can account for thousands of pounds of difference between quotes for what looks like the same property.
- Choosing on price alone without checking Gas Safe registration. It’s illegal for anyone unregistered to carry out gas work, and it voids both your safety and, often, your home insurance if something goes wrong.
- Underestimating radiator sizing. A radiator that’s undersized for the room it’s heating will leave that room permanently colder than the rest of the house — sizing should be based on the room, not a flat number per property.
- Skipping the site survey. A phone-quoted price without anyone seeing the property, the existing pipework, and the boiler location isn’t a reliable number — treat it as a rough starting estimate at best.
When This Isn’t a Planned Installation — It’s an Emergency
If your current heating has broken down completely rather than simply being due for an upgrade — no heat, no hot water, especially with vulnerable people in the property — that’s a same-day call, not a quote to schedule for next month. See our Emergency Plumbing page for rapid-response cover, or call the 24-hour line below. For boiler-specific servicing and repairs on an existing system, our Boiler Service page covers what a routine visit involves.
FAQs
How much does central heating installation cost? A full UK central heating installation typically costs £3,500–£9,000+ depending on property size, existing pipework, and boiler type. In London specifically, budget £4,000–£9,000+ for a standard 3-bed property.
How much does it cost to install central heating in a 3 bedroom house? In London, typically £4,000–£9,000 for a full system with a combi or system boiler and 8–10 radiators, assuming usable existing pipework.
How much does a new central heating system cost? It depends heavily on property size and whether pipework already exists: from around £3,000 for a small flat to £10,000–£14,000+ for a larger home or a property being heated from scratch.
How much does gas central heating cost? Gas central heating installation costs are broadly in line with the ranges above. Gas remains one of the cheaper fuel types to run day-to-day compared with electric heating, though running costs depend on current energy prices.
Can you install central heating in a house with no existing system? Yes. It costs more than a like-for-like replacement — typically £1,000–£3,000+ more — because pipework has to be run from scratch, often involving lifting sections of flooring.
How long does central heating installation take? A smaller property with existing pipework can take 2–3 days. Larger homes or from-scratch installations can take a week or more.
Does central heating installation include a boiler? Yes — a full central heating installation includes the boiler as a core component, sized to suit the property’s heating and hot water demand.
Does central heating installation include radiators? Yes, radiators sized for each room are part of a full installation, along with the pipework connecting them and the controls that operate the system.
What is included in a central heating installation? The boiler, radiators, pipework, heating controls (thermostat, TRVs, programmer), a system flush, and commissioning with the Benchmark Checklist and Building Regulations notification.
What factors affect central heating installation costs? Mainly: number of radiators, whether existing pipework can be reused, boiler size and type, property access and floor type, and local labour rates.
Get an Accurate Price for Your Property
Market guide prices are a starting point, not a quote — the only way to get an accurate figure is a site visit that accounts for your actual pipework, boiler position, and radiator needs. Call OnTime Plumbers on 08000 584799, 020 3831 1777, or 020 8054 6069 for an assessment. Engineers are Gas Safe registered and fully insured, covering Greater London, Essex, Hertfordshire, and Surrey.