Foam board insulation insect damage in attic

This foam board has some type of insect damage in the attic. Has anyone seen this type of damage and been able to determine the cause. There was no insect-damaged wood found in the home and no evidence of wood destroying insects. The only thing I found was mud dauber nests in the attic. Would mud daubers lay eggs in the foam board?

Don’t rule out termites. I’ve seen them burrow through drywall in the same manner. They aren’t limited to wood.

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Was the board against a gable end?

I have seen ants. But not in an attic


Thanks, Thomas,
I haven’t ruled out termites but I couldn’t find any other evidence of them. I returned to the attic a second time after I was done with the inspection and still couldn’t find any damaged wood.

Yes, Mark, it was foam board against a gable end.

Thanks Bryce,
I searched the attic a second time and couldn’t find any ant evidence. The only insect evidence I could find was mud daubers.

The second picture, with my finger in it, has some residue in the foam that feels and looks like sand.

There may be termite activity on the gable end siding.
What you’re viewing is when they lose their way.
Or… it’s a wasp.
I tend to go towards the wasp thingy.


Marc’s one of the best in the business in these situations. I would take his word over mine, but don’t rule out termites… :stuck_out_tongue: :wink:

Thanks again Marc,

The gable end siding is vinyl, the home is brick. Crawlspace is encapsulated and conditioned with treated sills. I couldn’t find termites or ant evidence anywhere. I am going to send the pic to the Indiana State Chemist Investigator just to cover all bases.

Keep in mind the vinyl siding is fastened to something. Doubt it’s brick.
It may be covering wood siding or furring strips for attachment.
Good luck :cowboy_hat_face:

While it may be frustrating to you personally, you can defer to a pest professional.

Note that it could be termites who live in the wood, but traverse the foam. Termites leave very little visible damage on wood, preferring to munch on the inside.

How much access do you have to this attic for return visits?

All I can say is O M G

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I understand Marc, I have previously found termite damage in the center of the rafters in a home built on a slab. The buggers had apparently made their way up an old chimney (previous leak at the roof flashing), and into the attic.

If this is termite activity, they must have crawled up the wood studs inside the exterior wall, but it is possible, I’ve seen it before.

I have deferred this one to the office of the Indiana State Chemist.

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Will you be able to report back on what State Chemist finds? Inquiring minds…