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severaltypesofnerd | Posted in GBA Pro Help on

I’ve just found beetles (see picture). I know the signs, little holes in the wood all over.
This is on a 1925 stucco home in the San Francisco Bay Area fog belt. The evidence was found on a open foundation vent that’s not protected from weather (apparently never painted since 1925).

Similar beetle damage appears on a decades old stored wood pile on the other side of the house, which cannot be moved because of the owner.

I’m considering painting over this, then recommending monitoring for additional holes appearing. Your thoughts? In the picture the plywood is a modern shear wall, outside is the other direction.

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  1. walta100 | | #1

    That looks like powder post beetle damage this insect is only second termites for the damage to homes.
    I recommend having a pests control company identify your insect.

    It would not surprise me if the recordation was to have the home tented for treatment.

    If you neighbor insists on keeping infected wood try getting the city to declare it a public nuance and force it removal.


  2. Expert Member
    Peter Engle | | #2

    That photo is crisp enough that you can see the interiors of the holes are weathered. This means that the damage is most likely very old. A close inspection of all the damage can usually determine whether there are any signs of current activity. The current standard treatment for local damage is a water-borne borate spray (no VOC's). Widespread activity requires tenting and nasty gassing of the whole house.

    A second opinion from a licensed pest control company would be a good idea, specifically one with powder post beetle expertise. of course be careful of recommendations for unnecessary and expensive treatments.

    These critters do their damage relatively slowly. A paint, watch and monitor approach is not a bad idea.

  3. severaltypesofnerd | | #3

    Here is some more on powderpost beetles:

    My only concern with the paint approach is if the beetles will just exit another way, avoiding the newly painted surfaces. Maybe I'll do the borate spray deep into the old holes, then patch and paint..

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