Listed buildings and conservation areas
The report mentions a cob wall next to a hard cement plinth. Has damp held at the base been tested, or only named?
Damp held at the base has only been named, not tested. A cob wall is an earth wall, and a hard cement plinth is a dense skirt against its foot. The report puts those two side by side. It does not give moisture readings through the cob, and it does not show that water is actually held there. The survey has not decided the plinth must come off. Listing covers the wall, and this visit does not grant consent to cut it back.
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?
Cob is a mass earth wall that needs to shed water and then dry. A hard cement plinth does not dry in the same way and can hold splash against the earth, which is why the junction is named. Naming is not a meter profile or a run of readings. The base may be wet, or the skirt may sit on cob that is currently dry. This visit did not separate those.
Tell the solicitor the plinth was named against the cob and the damp was not tested. A cob specialist can advise if the junction needs a closer look, without this report specifying that the cement comes off. Altering a listed cob wall can need consent, which the survey does not grant. The lender has no moisture profile. Leave the plinth in place until someone who understands cob has actually investigated it.
What should you ask your surveyor?
- Was damp at the base of the cob only named?
- Did you leave the cob without moisture readings?
- Has the visit avoided deciding that the plinth must come off?
What are the typical next steps?
- Treat damp at the plinth as named, not tested.
- Ask a cob specialist if the junction needs a real investigation.
- Tell the solicitor no consent to alter the wall was given.
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 cement plinth always trap water in cob?
The survey has not said always. A hard plinth can hold moisture against earth, which is why the junction was named. This wall was not tested, so the mechanism is not a result. Some plinths sit against cob that is currently dry. The report does not choose for this house.
If the cob face looks even, is the base dry?
No. An even earth face can hide a wet foot behind a cement skirt. The survey looked at the pairing and did not take readings. A fair render or a fair cob surface above the plinth is not a test of the junction. Damp at the base stays only named.