Age and type of house
What should a survey of a barn conversion keep separate from the planning papers?
The survey describes the building it could see: damp walls, the roof, the floor, the services that were visible. Planning permission and building-regulations approval are council records. GOV.UK treats building-regulations approval as its own process. A home survey does not search that file and does not grant the change of use.
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?
A converted barn can be dry and well built, or it can hide a concrete floor with no damp protection and a roof that was never relined. Those are survey comments. Whether the use as a house was authorised is a solicitor’s search. You can have papers and still have a leaking roof. You can have a sound roof and still have a planning problem.
Ask the solicitor for the permission, the conditions, and any completion certificate. Ask the surveyor which parts of the conversion they could not see, such as the floor void or the inner face of a lined wall. Do not let one document stand in for the other when you talk to the seller about price.
What should you ask your surveyor?
- Which defects are about condition, regardless of the paperwork?
- Which limits are because the conversion is lined out?
- What should the solicitor obtain that you did not check?
What are the typical next steps?
- Read the permission and the survey side by side with your solicitor.
- Do not treat a pretty interior as evidence the change of use was signed off.
- If papers are missing, ask the solicitor what the council can still say, and do not invent a fine.
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 completion certificate prove the barn is dry?
No. It records a building-control outcome at the time. It is not a survey of today’s roof or damp.
Is a barn conversion non-standard construction?
Not by the word conversion. The survey should say what the walls and roof actually are.