Only property that borders us with animals is to the south, 6 horses & 30 chickens on 10 acres of pasture, 4 indoor dogs & 2 barn cats.
They claim to have rat problems in their coop, so my plan is a deep concrete footing w/2' high walls as the floor of my chicken coop, corrugated metal sides. Plan to backfill over the concrete footing with dirt, and install some 1/4" tubing or pipe (stainless steel) vertically through the foundation footing before it sets so worms and bugs can still enter the coop via underground and water can drain out, but rodents cannot. My understanding is rats can fit through a 1/2" diameter pipe no problem, but anything smaller is too tight for them.
I have been purposefully trying to over design the coop for the better part of a year to keep rodents & wild weasels out...the damn weasels pups love to play in the stalls behind our barn for some reason, I suspect it's because the insulated tack room was infested by mice due to neglect from the previous owner.
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