In mouse exclusion, my understanding is that when blocking the entrance/exit hole the most important objective is to stop all air drafts. With no air drafts the rodent doesn't realize that a hole exists. If this is correct, what about pheromones? Don't pheromones attract the rodents as well? I use foam to do exclusions and sometimes the rodents chew through, but most of the time they do not.
I think that foam is a good immediate way to close off entry points or to fill large holes, but once it dries rats and mice will easily gnaw through it again. Better would be to permanently close that opening as soon as possible with some more impermeable material like metal flashing or caulking or concrete, depending on where the hole is. You might even shove a wad of copper or stainless steel mesh (Univar sells both) into the hole before then filling it with the expanding foam, as mice and rats appear to be deterred from gnawing by the wire materials.
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