Boiler cost vs installation labour
Where your money actually goes
When people search for boiler costs, they’re rarely confused about the boiler itself. What they’re really trying to understand is why one quote comes in at £1,900 and another at £4,200 — for what looks like the same job.
This page explains that gap honestly — based on what actually happens on real installations across London homes (not brochure pricing).
In many installs, the boiler is ~35–50% of the total — the rest is labour & compliance.
Gas checks, flushing, controls and commissioning are where good installs separate.
Access, parking and older pipework can turn a “simple” job into a full day+.
If you’re building a clearer picture of what drives boiler prices in London, these tie in well:
The common assumption that causes confusion
Most homeowners assume the boiler is the expensive part: a metal box, some pipes, a few hours of fitting.
So when someone sees “Boiler only £899”, it’s natural to think installation should be a small add-on.
The boiler is only one piece. The real value (and the real risk) is the work around it: sizing, safety checks, system health, controls, commissioning, and legal documentation.
The real cost split: boiler vs labour
On most London installations, the boiler unit itself accounts for roughly 35–50% of the total installed cost.
| Item | Typical share of total | What it covers |
|---|---|---|
| Boiler unit | ~35–50% | The appliance itself (model, output, warranty tier) |
| Labour + safety + compliance | ~50–65% | Removal, gas work, upgrades, flushing, controls, commissioning, registration |
Total installed cost: £3,200
Boiler unit: ~£1,200
Labour, safety, compliance & setup: ~£2,000
That ~£2,000 is not “fitting time”. It’s everything required to make the installation safe, legal, efficient, and reliable for years — not months.
What installation labour actually includes
Comparison sites rarely explain this clearly. Installation isn’t just connecting a boiler and leaving.
1) Removing the existing boiler properly
- Draining the heating system safely
- Dealing with seized valves and fragile pipework
- Disposing of old components legally
In older London properties, what looks simple can unravel quickly once work starts.
2) Gas safety and pipe sizing
- Checking existing gas pipe diameter
- Upgrading undersized supplies (very common)
- Pressure testing and safety checks
This work is non-negotiable and takes time to do correctly.
3) System flushing and protection
- Powerflushing or chemical flushing
- Installing a magnetic filter (where appropriate)
- Balancing radiators
Skipping this is one of the main reasons “cheap” boilers fail early.
4) Controls and efficiency setup
- Thermostat installation and configuration
- Programmer setup
- Boiler modulation and efficiency tuning
Many low-cost installs skip optimisation — so bills stay high despite a new boiler.
5) Legal compliance and documentation
- Gas Safe registration
- Benchmark log completion
- Manufacturer warranty activation
Miss any of this and warranties can be void, sales get complicated, and insurance claims can fail.
If a quote feels “too cheap”, send photos of the boiler + pipework and we’ll explain what might be missing. Call 07727 154746 or use our contact page.
Why cheap boiler installs usually cost more later
We see a common pattern: someone chooses an install advertised as “New boiler fitted from £1,999”.
- Basic boiler supplied
- Flush rushed or skipped
- Old pipework left untouched
- Minimal commissioning
- Warranty not fully registered
Within months, problems start to appear: noise, pressure loss, uneven heating. The boiler wasn’t cheap — the work around it was.
Why labour costs are higher in London
London installations come with challenges that don’t exist elsewhere:
- No parking or restricted access
- Congestion delays
- Flats above shops
- Shared flues and communal services
- Victorian / Edwardian pipework and layout quirks
A job that might take half a day outside London can easily stretch into a full day (or more) here. That isn’t inefficiency — it’s reality.
For the wider picture, this sits inside our hub: boiler installation costs across London (full guide) .
Boiler cost vs labour FAQs
Is labour really more expensive than the boiler?
Often, yes. The boiler might be 35–50% of the total. The rest is the work that makes it safe, compliant and reliable.
What’s the biggest “hidden” labour cost?
Gas pipe upgrades, safe testing, and doing the system prep properly (flush/protection/commissioning) are the usual big ones.
Why do online “from £X” deals rarely match real quotes?
Because they assume a best-case property: suitable gas supply, clean system, easy access and a straightforward flue route.
How can I get a realistic quote quickly?
Send photos of the boiler, the pipework underneath, and the flue route (if visible). That usually removes most uncertainty.
Want a realistic breakdown for your home? Call 07727 154746, email info@aragas.co.uk, or send photos via our contact page.
ARA Services Ltd • Durning Hall, Suite 14, Hyat Hub 14, Earlham Grove, London E7 9AB • Hours: Mon–Sat 24 hours; Sunday 6:00am–5:00pm.