Back-Boiler Log Burner Installation Cost (UK 2026)
A boiler stove heats your central heating system as a side effect of being lit. It's the most expensive log burner scenario in the UK at £5,000–£8,000+typical, but it's also the only scenario where the stove pays you back in gas/oil savings.
The short answer
UK 2026 typical: £5,000–£8,000total installed for a back-boiler integration. That's £2,000–£4,000 over a standard install, driven by the boiler stove (£1,200–£3,500+ vs £950 baseline) and the plumbing integration (£2,000–£3,500 for pump, mixing valve, expansion vessel, safety pipework, and commissioning).
Get your back-boiler estimate
Pick "Back-boiler (heats central heating)" on step 5. The calculator applies the scenario multiplier and assumes a HETAS+plumbing competent installer.
Open the calculator →How a back-boiler stove works
A boiler stove (sometimes called a "back-boiler" stove) has an integral heat exchanger sitting inside the firebox. As the stove burns, hot water circulates from the heat exchanger into your central heating system, typically feeding radiators and/or domestic hot water.
Most boiler stoves split their output: e.g. 5kW to the room + 10kW to the water side, or 3kW to the room + 12kW to water. They supplement rather than replace a main boiler — output isn't typically enough to heat a full UK house in winter without the gas/oil boiler also running.
Plumbing scope and cost
A modern (pumped) back-boiler integration in the UK in 2026 requires:
- Circulating pumpon the stove's flow circuit (£100–£250)
- Thermostatic mixing valve to prevent return water below 65°C from shocking the firebox (£150–£300)
- Expansion vessel or feed-and-expansion tank, depending on sealed vs open-vented system (£150–£400)
- Safety relief pipework — discharge to outside, sized correctly (£200–£500)
- 22–28mm pipework from stove to existing manifold or cylinder — adds £400–£1,200 depending on run
- Labour and commissioning — 1–2 days plumbing work on top of the standard stove install
Total plumbing element: £2,000–£3,500 on top of the standard stove install. If you have a sealed (pressurised) central heating system, add a thermal buffer vessel (£400–£800) to protect from overheating.
HETAS access — specialist
Fewer than 40% of HETAS-registered installers carry the dual solid-fuel + plumbing competencies needed for back-boiler work. Use the HETAS Find Installer search and filter for "boiler stove" or "central heating" capability specifically. A Gas Safe engineer may also need to interface with your existing gas boiler.
Pumped vs gravity-fed
- Pumped (modern standard): circulating pump moves the hot water through the system. Responsive, works in smaller-diameter pipework (22–28mm), easier to integrate with existing central heating. Default for new UK installs.
- Gravity-fed (open-vented, older): relies on the convection difference between hot and cool water. Needs 28mm fat pipework, very large feed-and-expansion tanks, and the cylinder positioned higher than the stove. Rarely fitted to new installs in 2026.
Recommended boiler stoves
- Hunter Herald 5 Eco with back-boiler — best UK value at this price point. Established design, strong dealer network. Hunter guide →
- Stratford Ecoboiler EB12HE+— Arada's boiler-specialist line, 12kW total output.
- Clearview Solution 500SB — 6kW room + 10,000 BTU integral boiler. Premium UK-made (note OPSS context). Clearview context →
Get 3 quotes from HETAS specialists in back-boiler installs
Boiler-stove integration needs combined HETAS + plumbing competency. We match you with installers who do both.
Find an installer →Frequently asked questions
How much does a back-boiler log burner cost to install?
UK 2026: £5,000–£8,000 total installed. The stove itself starts around £1,200 and rises to £3,500+ for higher-output boiler models, plus £2,000–£3,500 for the plumbing integration (pumped circulation, thermostatic mixing valve, expansion vessel, safety relief pipework).
Will a back-boiler stove replace my central heating boiler?
Usually no — it supplements it. Output is typically 5–15kW to the water side; not enough to heat a full UK house in winter without the main boiler running too. Best for cutting gas/oil consumption when you're using the stove anyway, not for full off-grid operation.
Can any HETAS-registered installer do back-boiler work?
No — fewer than 40% of HETAS installers carry dual solid-fuel + plumbing competencies. Use the HETAS Find Installer search at hetas.co.uk and specifically look for "boiler stove" or "central heating" capability. A Gas Safe engineer may also be required for the central heating interface.
Pumped vs gravity-fed system — which is better?
Pumped is now the modern UK standard. It requires a circulating pump, thermostatic mixing valve (to prevent cold return water shocking the firebox), and a small expansion vessel. Gravity-fed needs fat 28mm pipework and very large feed-and-expansion tanks; rarely fitted to new installs.
Do I need a thermal store with a back-boiler stove?
For a sealed (pressurised) central heating system, yes — typically a small thermal/buffer vessel (£400–£800 parts alone) to protect from overheating. For an open-vented system, the feed-and-expansion tank performs that role.