We are a commune of inquiring, skeptical, politically centrist, capitalist, anglophile, traditionalist New England Yankee humans, humanoids, and animals with many interests beyond and above politics. Each of us has had a high-school education (or GED), but all had ADD so didn't pay attention very well, especially the dogs. Each one of us does "try my best to be just like I am," and none of us enjoys working for others, including for Maggie, from whom we receive neither a nickel nor a dime. Freedom from nags, cranks, government, do-gooders, control-freaks and idiots is all that we ask for.
I guess we don't have hornets here. We have wasps, mostly yellow-jackets, which make a papery kind of nest, and then we have mud-daubers, which make a clayey-looking next, usually smaller than the one in your picture. Mud-daubers almost never sting, and they prey on spiders, especially black widows. Wasps sting like crazy, of course, and from what I read hornets have a particularly bad sting.
I saw my younger sister get stung by a whole nest of them on our farm when we were under six. I've practiced indiscriminate genocide on all hornets, yellow jackets, everything except bumblebees and honeybees ever since....
The number of nests varies a lot here year to year. Some years the yellow jackets have nests in every little overhang, cranny, and all over the eaves. Other years there are very few. I usually leave them alone and watch their comings and goings. One year I think there was a big fight or plague because dead and dying wasps and larvae were falling onto the ground from a nest behind some siding. Honeybees can be worse, I once saw an old house where the bees had taken over the inside of a whole wall. The honey was just oozing through and dripping down the wall.
That said, if I get stung I clean them buggers out. Darwinian selection in action.
Smart move! I had a bumble bee nest within 5 feet of my truck park spot last year ... I let them go because they are pollinators and we had an agreement, you don't sting me, I don't kill your community. Hornets... YIKES... I don't even kill them around the house when they fly by and hang around, the pheromone thing, heard the community would come get you!! FYI, use wasp killer on any paper nesting wasps, even if they aren't there... I kills the pheromone and they won't come back to that spot. Move em off and out in the winter.
We have a local business where the founder figured out a way to freeze nests of stinging insects, and using centrifuges isolate the venom, which the company then sold to pharmaceutical companies for antivenom purposes. They had crews that would come around at night with liquid nitrogen, freeze and remove the nests gratis, and depart with their booty. It was real helpful to a lot of folks who had nests where they didn't want them.
It's nice to be an animal lover but if I were you I would have a professional exterminator destroy that nest immediately. The wasps use the wood from the shakes as material for their nests. Eventually they will spread all over your roof by finding cracks and other places under and near the shakes. Last August my wife (the gardener) spent a very bad night in the hospital because of a serious reaction from a paper wasp sting. You guessed it, we had an older shake roof that was infested with wasps. We now have a new composition roof.