I've seen many photos of exposed comb built by bees but this is the first time I've ever actually seen it and wouldn't expect to have seen it built in a Northern climate.
I was told of a church just up the road from me with a huge honey bee problem. Yesterday, we took a ride up and found bees going in many openings in the attic gables (front & rear,) through the attic vents and the steeple. On the front of the church, just by the gable vent, the bees built enough exposed comb to perhaps fill a medium super. Too high for me to see brood or honey, but it is still very light in color so I'm guessing it was a recent swarm that found no place to go.
I'm not interested in climbing a tall ladder to do a removal of the exposed comb. (My days of working tall ladders are behind me,) but it would be interesting to get inside the attic and see just what this colony or likely multiple colonies have created. From the traffic going in and out, it must be huge. Removing comb from the interior could be a possibility. If nothing else, it would be a prime location for swarm traps. (Being the lazy beekeeper that I am, this is my preference.)
This is a small, seasonal church so I'll have to track down a contact person. If I get a chance, I'll try to get a photo of the exposed comb.