Damp and moisture meters
How should a buyer separate a string course, an open joint and a damp patch on the bedroom lining below when all three are mentioned together?
Separate the string course, the open joint and the damp patch on the bedroom lining. A string course is a projecting band on the outside wall. An open joint is a gap in that band or beside it. The patch is an internal mark below, on the lining. The survey has named the three in one place. It has not shown that the joint feeds the patch, has not water-tested the course, and has not decided the cause of the mark 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?
A string course is meant to throw water off the face, and an open joint can hold water on its top. That is a plausible path, which is why the three notes are written together. The bedroom lining can be marked by condensation, a spill or a leak, and those can look alike once dry. The visit did not open the joint, spray it, or trace a path down to the lining.
Tell the solicitor the outside joint and the inside patch were not linked by a test. If you need the cause, a damp or roofing inspection can look at the course and the lining together, which this survey did not complete. Do not rebuild the string course solely because a bedroom has a mark. The lender has three observations, not a leak diagram. Any repair waits on a proper link between the joint and the patch.
What should you ask your surveyor?
- Did you keep the string course, the joint and the patch as three notes?
- Was any path from the joint to the lining left untested?
- Have you avoided naming the cause of the bedroom mark?
What are the typical next steps?
- Keep the course, the open joint and the patch separate.
- Ask for a damp inspection if the mark must be linked to the joint.
- Tell the solicitor no water path was proved.
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 projecting course always protect the wall below?
No. It is meant to throw water clear, but an open joint can hold water on the top of the projection. The survey did not test which is happening here. A string course is not automatically a damp-proof detail. Protection was not demonstrated, and failure was not demonstrated either.
If the bedroom patch is small, can the joint be ignored?
Size does not decide the link. A small patch can have a local cause, and an open joint can be irrelevant to it. The survey did not measure the patch or test the joint. Ignoring the joint, or blaming it, would both go beyond the three notes. The cause stays open.