Subsidence, settlement and heave
The bottom timber sleepers of a garden wall are rotten and the house plinth is dry. Which structure is the rot about?
The rot is about the timber sleeper wall in the garden, not about the house. The bottom sleepers are rotten, which is decay in that retaining wall where the timber meets the ground. The house plinth is dry, so the inspection has not carried the rot across to the house. The survey has recorded a failed or failing garden wall of sleepers, and a dry plinth. It has not decided that the house is subsiding, and it has not decided that the sleeper rot is a damp path into the building. The structure in the sentence is the garden wall.
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?
Timber sleepers used as a low retaining wall sit in damp soil and rot from the bottom. That is a grounds defect: the wall that holds the garden may be losing the section that does the holding. A house plinth is a different structure, and here it was dry. Dry masonry does not prove the sleepers are sound, and rotten sleepers do not prove the plinth is damp. Mixing them would turn a garden wall into a storey about the house the survey did not tell.
Tell the solicitor the rotten sleepers are the garden retaining wall, and that the house plinth was dry. If the wall holds up a bank that could affect a path or a neighbour, say that as a grounds issue, not as subsidence of the house. Replacing sleepers is a garden repair someone may specify later. The survey has not specified it and has not priced it. Do not notify an insurer of house movement on the strength of timber that is rotting in the garden.
What should you ask your surveyor?
- Which sleepers are rotten, and is that the garden wall rather than the house?
- Was the house plinth dry on the day you saw it?
- Have you linked this rot to movement or damp in the house?
What are the typical next steps?
- Keep the rot on the garden sleeper wall.
- Do not report the dry house plinth as part of that decay.
- Do not notify house subsidence from rotten garden timber.
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
If the sleepers hold a bank near the house, is the house moving?
The survey has not said so. Nearness is not movement. The rot is in the bottom sleepers of the garden wall, and the house plinth is dry. No link to subsidence of the house has been made. A bank and a rotten wall are a grounds note until someone shows an effect on the building.
Does a dry plinth mean the sleepers can be ignored?
No. The plinth being dry keeps the rot off the house. It does not repair the sleepers. The bottom timbers of the garden wall are still rotten. That wall is the structure the note is about, whether or not the house itself is dry.