Chimneys and parapets
Nothing on the visit sampled a corbelled breast, opened the hearth trimmer or tested joists notched around the hearth. What has to stay undecided?
The corbel, the hearth trimmer and the notched joists all stay undecided. Nothing on the visit sampled the corbelled breast, opened the trimmer, or tested the joists notched around the hearth. A corbel is the brickwork that steps out to carry the breast where the stack reduces. The trimmer frames the hearth in the floor, and notches cut joists to clear that hearth. The survey has recorded the limits of the visit. It has not decided those timbers are sound, and it has not decided the corbel is cracked or intact inside.
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?
Corbelling is projecting brick that lets a breast narrow or widen as it rises. A plastered face hides whether that projection is cracked. At the hearth, a trimmer frames an opening so ordinary joists do not run under the slab. Notches cut timber out of those joists, and what is left was not seen. Strength, decay and any split at a notch stay unknown because nothing was opened on this visit.
Tell the solicitor that the breast, the trimmer and the notched joists were not opened and remain undecided. If the hearth is to be altered, or if the rooms show distortion, a structural specialist can inspect those timbers by opening up, which this home survey did not do. Do not read a decorated hearth as a sound floor. The lender has the same limit in the report: no test of the joists and no sample of the corbel. Leave any opening-up as a separate instruction.
What should you ask your surveyor?
- Did you leave the corbelled breast unsampled behind the finishes?
- Was the hearth trimmer left unopened on this visit?
- Were the notched joists named but not tested?
What are the typical next steps?
- Leave the corbel, trimmer and notches undecided.
- Ask a structural specialist if those timbers need opening up.
- Tell the solicitor the hearth was not proved sound.
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 level hearth slab mean the trimmer is sound?
No. The slab is the surface you walk on. The trimmer is the timber framed around it, and it was not opened. A level finish can hide a notch, decay or a poor bearing. The survey did not test those joists. The slab does not decide the floor around the hearth.
If the breast plaster is uncracked, is the corbel proved?
No. Corbelling can be cracked in the brick bond and still carry sound-looking plaster. The visit did not sample the breast. An uncracked face is not a test of the projection. The way the stack is carried stays undecided until someone opens it or calculates it from what is actually there.