Age and type of house
If a survey says “steel frame”, is the house a BISF?
Not necessarily. BISF is one post-war steel system. Other steel frames exist, including modern ones. The survey should say what it could see and what it is inferring. “Steel frame” without a system name is a prompt to ask more, not a designated-defective label and not a mortgage refusal this page can issue.
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?
Cladding can be steel sheet, render or a brick skin. The frame may be hidden. A surveyor who has not seen the frame should not name a repair scheme. Designated defective types are a legal list your solicitor checks when a concrete system is alleged. Steel is not that list by default.
Ask the lender what they need once the construction is described honestly. Ask the surveyor what would confirm the system: openings, drawings, or a specialist. There is no RICS price for naming a frame. Do not pay for a PRC concrete certificate on a steel house.
What should you ask your surveyor?
- What did you see that made you say steel?
- Are you naming a system or only a material?
- What further step would identify it?
What are the typical next steps?
- Tell the lender the words the survey actually uses.
- Do not accept a concrete-house repair quote for a steel frame.
- If the system matters, instruct someone who will identify it, with a written scope.
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 a steel beam in a loft a steel-framed house?
No. A single beam is an alteration. A framed house is the structure of the walls. The survey should not confuse them.
Does a brick skin mean the frame is protected forever?
No. The skin can look fair while the frame needs comment. If they could not see the frame, they should say so.