Condition ratings
Staining directly under a window is called penetrating damp. Why is that not the same box as a tide mark at skirting level?
Not the same box. Staining directly under a window, which the report calls penetrating damp, is water at the opening. A tide mark at skirting level is a low horizontal line on the wall. They can both be damp and still be different elements, different paths, and different ratings. Do not file the sill stain in the skirting box because both involve moisture.
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?
Penetrating damp, as this report uses it, is moisture coming through at the window: the sill, the frame joint, or the wall around the opening. The stain sits directly under the window because that is where the water arrived. A tide mark at skirting level is a low line, often along the base of a wall, and it is a different pattern. The surveyor has already chosen different words. Those patterns can carry different ratings. The opening might be rating 2, a repair that is not serious or urgent, while the skirting line is rating 3 if they call it serious, or the other way round. One moisture family does not force one number.
Do not merge them into a single damp scheme in your note to the agent. The what to do now note advises you about whichever element is rating 3, and it asks for written quotations before legal commitment for that element. It does not invoice the seller for both, and it does not rename penetrating damp as something else. Concealed cavities and the back of the plaster are not guaranteed sound in either place. Ask which box in the table holds the sill stain, and which holds the skirting mark, if either is rated. A builder who prices one treatment for both has not followed the report.
What should you ask your surveyor?
- Which rating is on the staining under the window?
- Is the skirting tide mark a different row?
- Did you keep penetrating damp as the name for the opening only?
What are the typical next steps?
- Keep the sill stain and the skirting mark in separate notes.
- Do not ask for one remedy to cover both unless the report links them.
- Quote the element that is actually rating 3.
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 both be rating 2?
Yes, if neither is serious or urgent. Two rating 2s are still two defects.
If the sill stain runs down to the skirting, is it one box?
Only if the report says the two marks are one path. A continuous stain should be described, not assumed.