Timber decay and woodworm
Flight holes are in the sarking boards and the rafters beside them look clean. Why should the rafters not be condemned with the boards?
The rafters should not be condemned with the boards, because the flight holes are in the sarking and the rafters beside them look clean. Sarking is the boarding on the slope. Holes in those boards are an insect note on the boards. Clean rafters next to them are different timber, and the survey has not moved the attack from one to the other. The report records where the holes are. It has not probed every rafter and it has not called the roof structure infested.
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?
Insect damage is judged on the piece that shows the holes, the dust and any softness, not on a neighbour that shows none. Old holes in sarking can be historic and limited to a lining that can be replaced without condemning the rafters. They can also still be active. The survey has not settled which, and a clean look is not a laboratory result. The reason not to condemn the rafters is the split actually recorded: holes in the boards, rafters looking clean.
Ask a timber specialist whether the holes in the sarking are active, and to check the rafters as the separate timbers they are. Tell the solicitor the flight holes are in the boards. Do not accept a price that replaces the rafters merely because the sarking is holed, unless a further look finds the rafters affected. The survey has not condemned the structure along with the lining.
What should you ask your surveyor?
- Are the flight holes in the sarking boards rather than the rafters?
- Do the rafters beside those boards look clean?
- Has the survey refused to condemn the rafters with the boards?
What are the typical next steps?
- Keep the insect note on the sarking, not on the clean rafters.
- Ask a timber specialist if the holes in the boards are active.
- Do not replace rafters unless a further look finds them affected.
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
If fresh dust is on the sarking, are the rafters infested too?
Not by that dust alone. Fresh dust would matter to the boards it lies on. The rafters beside them were recorded as looking clean, which is why they are not condemned with the boards. A specialist can check both. The survey has not transferred the attack from the sarking to the structure.
Are clean-looking rafters a guarantee against woodworm?
No. Looking clean is what the survey recorded, not a lifetime clearance and not a laboratory result. It is the reason those rafters are not condemned alongside the holed boards. Active attack can still be found if someone probes them. Until that happens, do not write the structure off, and do not pretend it was tested.