Treating woodworm with a cat in the house

[Tom9989]

Hi everyone.

We recently moved into an old stone cottage and discovered some woodworm. Most serious issues are in the basement, so we have been treating there with permethrin-based products. Also found a bit up in the ceiling/rafters (photos below), however, and wondering what to do. The main beam (top photo) is sweet chestnut so, I've heard, largely resistant to woodworm at its structural core. Our issue is we have a cat in the house, and so have been slow to treat with permethrin in the living space itself.

Also relevant here is that for last 10+ years, the house was only used as a summer holiday home. It was locked up and presumably very cold and damp in autumn/winter/spring. There were a couple of leaks in the roof (the woodworm problem overlaps with where the leaks were, for the most part), which we have been trying to fix up. We have now moved in for year-round living, and installed a wood stove, which we are using nightly and heating the space, alongside the oil heating. We also open windows and air the place out when we can. However, due to the old stone construction, our relative humidity is still high (usually above 70), fluctuating a lot with the weather.

Some specific questions:
1. If we were to treat with permethrin in the living space, how long do you think it would be until it was safe for the cat? We will be treating areas in the ceiling/roof where he won't be physically touching, though he will be in proximity.
2. What are the chances of us moving into the place year-round helping with this problem, without the need to use permethrin?
3. Is there anything else I can do to disrupt the life cycle of these beetles, without using toxic chemicals? A neighbour even suggested that painting with diesel is an old-school method of dealing with woodworm.





Thanks for any advice or suggestions!

 

[Cubist]

Your best defence against woodworm is to keep all timbers as dry as possible. Your heating and ventilation systems are vital in this regard and regular occupation of the property will be a major boon. Ensure that any and all leaks are properly repaired and that kitchens and bathrooms are equipped with extractor systems to minimise condensation accumulating and resting against exposed timbers. Keep an eye too on any ceiling voids immediately above kitchens and bathrooms as joist timbers there can prove problematic.

Theres some truth to the suggestion that when you find woodworm exit holes then theres no longer a problem. Personally I don't subscribe to this view as I see no reason to believe that beetles arriving later will not find such timbers attractive. That said, clean all surrounding areas of a previously affected timbers, and all others, and watch for any accumulations of frass - the sawdust like excreta nearby.

In terms of woodworm killers, some here will say they're pointless and dangerous but again, I personally disagree and will on occasion use it. Once it is throughly dry it is safe for pets and people so keep the cat out of the treated rooms until you're happy.

 

[Matt Green]

Ug. giving advice versus the risk of harming your cat.


I sought expert advice:

Fig. 1. Sir Duskington Bunns.

Dusk reckons I could be crazy to suggest using permethrin in a house with a cat even if you were brush treating only teh affected areas and they were out of contact with where a a cat would normally be. He also asks if you happen to have any Dreamies...?*

Some specific questions:
1. If we were to treat with permethrin in the living space, how long do you think it would be until it was safe for the cat? We will be treating areas in the ceiling/roof where he won't be physically touching, though he will be in proximity.
2. What are the chances of us moving into the place year-round helping with this problem, without the need to use permethrin?
3. Is there anything else I can do to disrupt the life cycle of these beetles, without using toxic chemicals? A neighbour even suggested that painting with diesel is an old-school method of dealing with woodworm.

1. That depends how much the cat likes rubbing up against and licking the affected areas.
2. Good, it will certainly help and it's not as if this is a structural issue.
3. Use of chemicals off label is not advised etec, etc. I would be inclined to fill the holes with beeswax and wait a few years to see if there is any new activity.


M.
*Just a couple to get him through the evening- he promises me he's going clean in the new year.

 

[paulc]

Have cat too. My first thought when I saw the thread title was "I wouldn't dream of using a cat to treat woodworm"

Had a major problem with fleas earlier in the year and was spraying an industrial strength permithrin spray everywhere. I would wait for his lordship to go outside before spraying, and it would be dry by the time he came in. No ill effects to report, and in conjunction with regular dosing of the cat, no sign of the fleas. Can't see spraying ceiling timbers will be an issue - Just keep the cat out of the room for a few hours to let the spray settle and dry.