Windows, doors and glazing
What does rot in one timber sash tell you about the other windows?
It tells you that sash has been wet long enough for the timber to soften. It does not condemn the rest of the elevation. A home survey should say which frames it could probe and which it only saw from the ground. Splicing a rotten bottom rail is a different job from replacing every window because the house is Victorian.
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?
Timber windows fail where water sits: the bottom rail, the cill and the joints. One bad sash on the weather face is common. The matching sash on the sheltered side may be sound. The surveyor does not remove the window to see the hidden joint. If they say “soft”, ask whether that was a hand test or a look at flaking paint.
Listed houses and conservation areas add a consent question the survey cannot answer. Even on an unlisted house, a quote to “uPVC the front” is a choice, not a finding. There is no RICS price for sash repair. Ask a joiner who repairs sashes to look at the ones named in the report.
What should you ask your surveyor?
- Which sashes are soft, and which did you not reach?
- Is the rot in the cill, the bottom rail, or the frame where it meets the wall?
- Would you expect a repair of those pieces, or are you saying the openings have distorted?
What are the typical next steps?
- Do not accept a whole-house window price based on one soft rail.
- If the house is listed or in a conservation area, ask the solicitor about consent before anyone specifies plastic frames.
- Keep paint failure and rot as separate sentences when you speak to a joiner.
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
Are sash cords a defect?
A broken cord means that sash will not stay open. It is ironmongery, not rot, unless the timber has gone as well.
Does new paint prove the timber is sound?
No. Paint hides soft wood for a while. The survey should say if it could not probe painted timber.