Boiler Bolt-On · Flue components
Extra flueing and additional bends
Some boiler positions need more flue pipe, direction changes or specialist components to reach a suitable outdoor terminal. The route must be designed for the selected boiler—not simply extended until it reaches a wall or roof.
Compare the routes
Short exit versus extended route
The examples are alternatives, not two flues fitted together. A longer route and bends affect the manufacturer’s permitted flue calculation, so every component must be checked for the chosen model.
Example A · short wall route
Example B · extensions and bends
How we work out the flue scope
Choose the boiler position
We assess safe siting, access and a suitable wall or roof terminal location.
Measure and calculate
We plan each section and bend against the selected manufacturer’s flue instructions and permitted effective length.
List every extra
The written quote identifies extensions, bends, terminal and any opening or making good beyond the standard pack scope.
What is involved
- Planning the approved flue route to a suitable external terminal.
- Fitting the specified extension pieces, bends, supports and terminal.
- Making the agreed wall or roof penetration and completing its finish.
- Checking the completed flue as part of boiler commissioning.
What we check at survey
- The selected boiler’s compatible flue system and maximum effective length.
- Each bend’s effect, route access, support and inspection requirements.
- Terminal clearances, nearby openings and property boundaries.
- Wall or roof construction and any related building work.
What affects the quote
- Number and type of manufacturer-approved extensions and bends.
- Flue diameter or system changes required for the chosen appliance.
- Access, supports, wall or roof penetration and weathering.
- Associated making good and any change of boiler position.
What your written quote includes
- The agreed route and all specified flue components.
- Which components are in the boiler pack and which are added.
- Installation, access, penetration, finishing and commissioning checks.
- Clear exclusions and conditions if survey changes the route.
Extra flueing questions
Can you add as many bends as needed?
No. The selected boiler’s instructions set limits and account for bends in the permitted route. We calculate the proposed arrangement before agreeing it.
Is one metre included as standard?
We will confirm the included flue kit and any allowance in your specific written boiler quote. This page does not promise a universal length.
Can I reuse my existing flue?
Only if it is compatible with the new appliance and the manufacturer permits it. The quote will identify the approved components to be fitted.
Would a vertical flue be better?
It may be an alternative where a suitable wall route is not available. The roof path, terminal, access and weathering are assessed separately.
Will longer flueing change the cost?
Extra approved parts, access and making good can affect the quote. We set out the actual scope and price after survey rather than offer a universal figure.
Ask about your flue route
Tell us your postcode and boiler location, plus photos of the nearby outside wall or roof. We will confirm the suitable route at survey.
Prefer the website form? Contact MPH Boilers and mention “Extra flueing and bends”.