Age and type of house
Render on a timber-frame house is cracked and stained. Has the survey seen the sheathing behind that render?
No. Cracked and stained render on a timber-frame house is a comment on the outside coat. Sheathing, studs and any membrane behind that render were not opened. A stain can mean water reached the coat, or only that dirt has stuck. The surveyor is not an asbestos inspector, and a cement-looking coat is not a sample. Timber behind an unopened render face has not been shown to be dry or rotten.
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?
Modern and older timber frames often sit behind a render carrier, mesh and a coat that is meant to keep rain off the sheathing. Cracks, hollow patches and green staining tell you about that coat and about water on the surface. They do not show the board or the studs. The survey can tap and look. It does not cut a window in the render to photograph the sheathing, and it does not send a sample to a lab as part of the ordinary visit.
Treat a rating on the render as a rating on the render. If the report recommends a specialist, that person needs to be told the frame was not seen, so they do not quote as if the timber had already been inspected. Do not call the coat asbestos because it is grey and hard. The surveyor is not an asbestos inspector, and breaking the coat to find out is not a buyer's job on a viewing. Note the stain, the crack pattern and the limit.
What should you ask your surveyor?
- Which faces of render were cracked or stained, and which faces looked intact?
- Did any opening, meter box or damaged patch let you see sheathing or studs?
- Is the rating about the coat only, with the frame recorded as not exposed?
What are the typical next steps?
- Quote the render comment to a renderer, not as a timber report.
- Do not drill or break the coat to sample it.
- Ask the firm to state clearly that the sheathing was not seen.
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 crack through render mean the studs are wet?
Not by itself. It means the coat is cracked. Wet studs are a further question that needs the coat opened or another sign the survey could already see.
Can the surveyor clear the coat of asbestos by looking?
No. Looking is not sampling, and the surveyor is not an asbestos inspector. Do not break the material to check.