Damp and moisture meters
Is a damp patch at the top of an internal wall usually rising damp?
Rarely. Rising damp is discussed at the base of walls that are in contact with the ground. A damp patch at the top of an internal wall is far more often a leak from above, a pipe, or a roof junction. Calling it rising damp ignores the height.
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?
An internal wall can be a partition with no contact with outside ground at all, or a party wall that only meets the ground at its base. A patch at the top, near the ceiling, points upstairs or into the loft: a failed flashing, a bathroom, a tank, a pipe in the floor void, or condensation on a cold ceiling junction. Water does not rise from the skirting to a high patch and leave the middle of the wall dry. A surveyor should say where on the wall the mark sits.
The inspection is visual. It does not open the floor above and does not guarantee the void. If the room over was not accessible, the report should say so rather than rename the stain. A stain that starts high and runs down is still not rising damp. Keep the seller conversation on the high-level cause. An injected course at skirting level does nothing for a leak at the ceiling line.
What should you ask your surveyor?
- How high is the patch, and is the wall a partition or a party wall?
- What sits on the other side: a bathroom, a loft, or another room?
- Is the skirting on this wall dry?
What are the typical next steps?
- Do not call a high patch on an internal wall rising damp when you write to the seller.
- Look at the room above, or the loft, before you look at the ground.
- If that room was not entered, treat the cause as still open.
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
Can a pipe in the floor above wet only the top of the wall?
Yes. A leak at the edge of a floor can show as a high patch and nowhere else.
Does a party wall have a damp-proof course you should blame?
Only if the pattern is at the base. A party wall can also be wet from the neighbour's side, which the survey may not have entered.