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Hello mwkozlowski,

My guess is that this is the work of a Hymenoptera of the superfamily Vepoidea. In the Netherlands Odynerus species of the subfamily Eumeninae produce similar constructs in walls. They are called (freely translated) Chimney wasps.
But I´m a Dipterist, not a Hymenopterist so hopefully someone comes along who knows what it actually is.

Greetings,

Ectemnius