Non-standard construction
Rust staining shows at skirting level where a steel might sit. Has the survey measured that steel?
No. Rust staining at skirting level is a mark on the finish, not a measured steel section. The surveyor can note colour, blistered paint and a damp board. They cannot give a thickness, a remaining section or a corrosion depth for metal that stayed inside the wall. Skirtings and fitted carpets were not stripped. A stain is a reason to investigate, not a certificate that a frame has failed or that it is intact.
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?
Steel stanchions in some post-war houses sit just behind the plaster at the corners and at the skirting. Orange stains, blown paint and a crack that follows a vertical line are clues that something ferrous is nearby and that water has reached it. Clues are not callipers. The visit does not cut the plaster, does not ultrasonic-test the steel, and does not say how much of the original section is left. A dry day can hide a leak that returns in winter.
Ask for the stain to be located: which room, which corner, how far up the wall. Then decide whether you need a specialist who is allowed to open that spot. Do not tell a lender the frame has a measured loss of section if all anyone has is a colour on the paint. Do not ignore the colour either. Rating 2 means repairs are needed but are not serious or urgent. Rating 3 means serious or urgent. The report should pick from what was seen, not from a guessed thickness.
What should you ask your surveyor?
- Where exactly is the stain, and does it line up with a corner or a joint?
- Did you expose any steel, or is the comment based on the finish only?
- Are you calling for investigation rather than stating a remaining thickness?
What are the typical next steps?
- Photograph the stain and keep that photo with the report.
- Do not quote a steel thickness the survey never measured.
- If you need the metal seen, arrange an opening-up inspection before you commit.
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
Is orange paint always a steel frame?
No. It can be a pipe, a bead, a fixing or an old leak. The survey should say what it could see, not force a system name.
Does a clean skirting elsewhere clear the whole frame?
No. One sound length of board does not measure steel in other corners. Each stain stands on its own.