Damp and moisture meters
Can a flat over a shop be wet from the shop below rather than from its own roof?
Yes. A flat over a shop can be damp from the unit underneath: a leaking pipe, a cold shop ceiling, or steam, showing on the flat's floor or lower wall. That is not the flat's roof. A survey of the flat usually cannot inspect the shop.
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?
The floor of the flat is the ceiling of the shop. Water from a shop kitchen, a WC, a refrigeration line or simply very cold, humid air can mark the flat from below. The stain is then on the floor edge, the skirting or the bottom of a wall, which people misread as rising damp even on an upper floor. The roof of the flat is a different element and may be sound. The surveyor instructed on the flat sees the flat. They do not have a right to inspect the shop just because it is downstairs.
A home survey does not guarantee concealed parts and does not lift fitted carpets as standard, so the deck between flat and shop may be hidden. Say clearly if the shop was not entered. Legal questions about the lease and who repairs the structure are for the solicitor, not for a moisture meter. Do not ask a roofer to retile because the bedroom floor over the shop is stained, until someone has separated the shop from the roof.
What should you ask your surveyor?
- Was the shop entered, or only the flat?
- Is the damp on the floor and lower wall, or at the ceiling?
- Which defect is the roof, and which might be the unit below?
What are the typical next steps?
- Do not treat a floor stain over a shop as a roof leak without looking at the height of the mark.
- Ask the solicitor who repairs the floor between the shop and the flat.
- If the shop was closed, write that limit into any decision. Do not invent what is below.
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 ground-floor flat over a basement shop differ?
The idea is the same. Moisture from the unit below can mark the flat. The survey still only covers what was entered.
Is steam from a takeaway a failed damp-proof course?
No. It is moisture from the use below. It may need ventilation and a repair to the separation, not a new course in the flat.