I wonder if there is a more sustainable way of dissuading rodents from ever entering a building.

I once had a terrible ant problem, they would always find their way into the kitchen. I tried a variety of products either intended to kill off the actual ant nests directly or trap the invaders, but there was always some quantity of ants remaining that would persist. Then I tried one product that was to simply be sprayed around the entrances like an invisible barrier, the ants would encounter it and just turn around. This turned out to be far more effective, and I felt like less of a jerk by not carpet bombing all the local ant nests.

I guess it might be harder to induce such behaviour in a rodent, I think the spray exploits the fact that ants leave chemical trails, so even if one of them figures out a path the rest wont follow. But the constant game of killing and collecting invaders must be exhausting.