What might be happening
Old exit holes are permanent marks and may not indicate insects are still active.
Before agreeing to treatment or extensive replacement, it is reasonable to ask what has actually been found, how far the damage extends and what is allowing it to happen.
What you can look for
Seek evidence such as fresh frass, new holes or beetles at the relevant season, and identify the likely species.
You do not need to start taking the building apart yourself. If access is difficult, ask the person inspecting it to explain what needs to be opened up and why. Photographs of hidden defects are useful, especially when you are comparing quotations.
Putting it right
If activity is confirmed, use appropriately targeted treatment and repair structural timber only where necessary.
Be wary of a quotation that deals only with the damaged wood and says nothing about the water or building defect behind it. Once the cause has been dealt with, the remaining timber can be checked and the necessary repairs planned.
When to call someone in
Indiscriminate spraying may cost money without addressing an active problem.
A carpenter or joiner may be right for a local timber repair. If the problem involves a leak, you may need a plumber or roofer first. Where supporting timbers have moved, sagged or seriously weakened, get advice from someone qualified to assess the structure.
Questions worth asking
- What evidence supports the diagnosis and proposed treatment?
- Which parts of the work are essential and which are optional?
- Will you put the findings, scope and exclusions in writing?