Does anyone have tips for designing an outbuilding to deter wild animals like groundhogs, mice, squirrels, snakes, etc. from entering the building? I already have a barn with a dirt floor and have experienced all of these creatures in my barn--don't want to repeat these experiences again in a new building. I would like to have a garage door in the new building. Will I have to build entirely out of concrete block--I hope not! Any ideas?