Age and type of house
The report places a gauged brick arch, the fanlight head and a slight sag in the voussoirs in one paragraph. Which of those were inspected, and which were merely named?
The gauged brick arch and the fanlight head were inspected as masonry and joinery that could be seen. The slight sag in the voussoirs was named as the look of the curve, not measured. Gauged work is soft brick rubbed to fine joints, and voussoirs are the wedge-shaped units. The survey has not calculated a deflection, has not opened the arch, and has not decided that it is failing. A slight sag in the wording is an appearance, not an instrument reading.
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?
Gauged arches are cut from soft brick so the joints are very fine. The fanlight head is the frame and glass under the arch, which is separate joinery. Voussoirs should follow a smooth curve. A slight sag means the line looked a little dropped to the eye, with no level in the note. The arch was not opened, so any iron bar and the bearings stay unseen.
Tell the solicitor the arch and the fanlight were seen, and that the sag was not measured. If the opening looks distorted in the flesh, a structural specialist can decide whether the arch needs calculation or opening-up. The home survey has not done either. The lender has no deflection figure. Do not rebuild a gauged arch because the curve was described as slightly out. Any work to it needs its own specification.
What should you ask your surveyor?
- Was the gauged arch inspected only as a visible face?
- Was the slight sag named rather than measured?
- Did you leave the fanlight head unopened behind the brick?
What are the typical next steps?
- Separate the visible arch from a sag that was not measured.
- Ask a structural specialist only if the opening is genuinely distorting.
- Tell the solicitor there is no deflection figure in the report.
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 gauged arch with fine joints have an iron bar inside?
Often these arches were built with a secret iron bar, but this visit did not find one and did not look for one by opening the soffit. Fine joints describe the face. They do not reveal a bar, a shoe or rust jacking. The survey has not said a bar is there, and it has not said the arch is sound without one.
If the fanlight glass is intact, is the arch true?
No. Intact glass says the fanlight has not broken. The arch is the brick over it, and the sag in the voussoirs was only named. The joinery can look fair while the curve looks slightly off, or the reverse. The survey did not use the glass as a test of the brick.