Damp and moisture meters
A solid floor is damp at the skirting and the middle of the slab reads dry. What edge detail is the likely note, and what membrane under the slab was not seen?
The likely note is the edge detail at the skirting, and the membrane under the slab was not seen. The solid floor is damp at the perimeter and the middle reads dry, which points at the junction of slab, wall and skirting rather than at a failure across the whole floor. A damp-proof membrane under the slab, if it exists, was not visible from above. The survey has recorded the edge damp and the drier middle. It has not seen that membrane, has not decided it is missing, and has not decided the slab is saturated. The pattern localises the note to the edge.
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?
Solid floors damp at the skirt often do so where the wall's damp course, the floor membrane and the plaster meet, or where a later screed bridges them. The middle staying dry is the clue that the slab surface is not uniformly wet. Nobody has lifted the middle to see a membrane, so dryness there is a surface reading, not a view of the plastic or the bitumen underneath. The survey should say the edge is the note and the membrane was not seen.
Ask a damp specialist to look at the edge detail: the skirting, the plaster, and how the floor meets the wall. Tell the solicitor the membrane under the slab was not seen, so no one should claim it is continuous. Do not fund a new floor on the theory the whole membrane has gone when the middle reads dry. The inspection has not opened the slab and has not produced that theory.
What should you ask your surveyor?
- How wide is the damp band at the skirting compared with the middle?
- Did you see any membrane, upstand or damp course at the edge?
- Are you limiting the note to the edge rather than the whole slab?
What are the typical next steps?
- Treat the edge detail at the skirting as the likely note.
- Record that the membrane under the slab was not seen.
- Ask a damp specialist to look at the floor-to-wall junction.
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 middle reads dry, is the membrane proved intact?
No. A dry middle is a surface reading of the slab. It does not show the membrane underneath, which the survey did not see. The likely note remains the damp edge at the skirting, not a certificate for a hidden sheet.
Does a new skirting mean the edge detail has been repaired?
No. A new skirting covers the junction. It does not show the membrane under the slab, and it does not explain the damp the survey found at that edge. Replacement timber is not a view of the floor build-up. New timber at the edge is a cover, not the slab membrane.