Timber decay and woodworm
Flight holes of a deathwatch type are in one oak beam, and the sapwood there is gone. Why has the survey not ordered a house-wide spray?
Not flight holes of a deathwatch type in one oak beam, where the sapwood has already gone, are an order for a house-wide spray. The holes are exits in that beam. Spent sapwood on one member is not a live attack mapped through the house, and the survey has not ordered a chemical treatment of every timber. Flight holes are not dust falling today. A visual survey records the beam it saw. It does not name a pesticide, and it does not send a spray through rooms with no such holes.
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?
This sort of damage is tied to damp hardwood, and it is the sapwood that is lost. When that sapwood has already gone, the holes can be old history in a beam with little left for an insect to use. Activity is a separate question, read from fresh bore dust, not from holes alone. This note does not claim that fresh dust. It claims holes, and sapwood already gone, in a single oak beam.
A timber specialist can look at that beam and say whether anything active remains, or whether the lost sapwood has reduced the section enough to matter. It is one member until evidence says otherwise. Do not accept a quotation that sprays the loft, the floors and the stairs because one oak beam has flight holes. The survey did not ask for that. It described the beam, and treatment is a later decision.
What should you ask your surveyor?
- Which oak beam has the holes, and was fresh bore dust present or absent?
- Is the damage limited to sapwood that has already gone from that beam?
- Are you ordering a treatment, or recording holes in one member?
What are the typical next steps?
- Limit the first specialist look to the oak beam named in the report.
- Do not commission a house-wide spray on the strength of flight holes alone.
- Ask whether any fresh dust was present before treatment is discussed at all.
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
Do these flight holes mean insects are active in the house now?
No. Holes show that insects left that oak beam at some time. Without fresh dust the survey has not called the attack active, and it has not ordered a spray.
Must every timber be treated because one oak beam has holes?
No. The holes are in one beam, and the sapwood there is already gone. The report does not name a pesticide or a house-wide treatment.