Probably a leak, wasps in the attic

Hello,

our house was completed in 2013. A few weeks ago, I noticed wasps in the attic. When I look at it from the outside, they come in on the upper right under the dormer, at the point where the dormer roof transitions into the "normal" bay. I haven’t checked it thoroughly yet because I’m waiting until it gets cold enough that all the wasps are gone. I assume they have built their nest somewhere there.

I see this as a classic construction defect, since the spot is obviously not sealed properly. Therefore, I intend to request the developer to make repairs, as I believe this is a warranty case. It is probably the sealing and possibly some "signs of wear" somewhere, where the wasps have sourced their nesting material.

What do you think?

Thanks and regards,
StarAce

just as a layman: I don’t know how far you get with a hole the size of a wasp as a construction defect, and whether it’s worth the effort. I would probably – if I get to it – seal it myself and that’s that.

The problem will be getting access, and with a new building, I think I can expect a tight house.