Electrics and gas
The boiler flue terminal looks close to a window. Has the survey measured that?
No. The survey does not measure the clearances a Gas Safe engineer uses, and it must not invent a distance. “Looks close” is a reason to have a registered engineer check it. It is not already a fail, and it is not a pass.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Terminals sit on walls near windows, doors, corners and boundaries. From the ground, foreshortening makes distances hard to judge, and a home survey is not a measured combustion check. The surveyor can say the terminal is beside an opening and that they did not measure it. They should not quote a clearance they did not take, and this page will not supply one. HSE expects the inspection of gas appliances to be done by an engineer on the Gas Safe Register. Ask that engineer whether this terminal position is acceptable for this boiler. Their answer replaces the glance.
A plume blowing at a window is worth mentioning to them. It is still not a measurement. Do not renegotiate from a number you have made up. Do not ignore the note because the boiler lit on the day. Lighting is not a siting check. Service papers may record the installation, and they may not mention the terminal at all. An owner-occupier seller is not automatically holding a landlord gas safety record for you. If the engineer says the terminal must be moved, that is a later quote from them, not a figure hidden in the survey.
What should you ask your surveyor?
- Which opening does the terminal sit near, and did you measure anything?
- Are you telling me to get a Gas Safe engineer, rather than stating a distance?
- Did you see damage to the terminal, as distinct from its position?
What are the typical next steps?
- Do not write a clearance figure into an email to the seller.
- Ask a Gas Safe registered engineer to check the terminal position.
- Keep their finding separate from the survey’s “not measured” sentence.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Does a plume prove the flue is in the wrong place?
No. It proves you can see a plume. Position is a measured check the survey did not do.
If the terminal is far from any window, has it passed?
No. Looking comfortable is not a Gas Safe inspection either.