When Top Gear did it's 'trip to the North Pole one guy went by dogsled. The dogteam ran better at night because it was colder and the dogs didn't overheat so easily. So sled dogs can overheat when working even when it is -10 below. Put sleddogs out at -60 and the'll curl up with nose under tail and be fine.
Of course these aren't sleddogs, but I am using it to illustrate that dogs can handle being outside in very tough conditions.
So what about animals with shorter coats? Well, horses don't have long coats, and they are 'energy neutral' right at freezing. The old rule of thumb is that if the horse's water was crusted over with a thin film of ice then the horse was at perfect temperature...any warmer or colder and the horse would have to spend energy cooling himself or warming himself.
White tail deer don't have thick coats either and they are living out in canadian winters just fine. Oh, the coat thickens up a little but in comparison to true arctic animals it is still pretty short.
For dogs, the key is that they are acclimated to it. If the plott hounds are outside all the time then they are going to be able to stand a lot colder temperatures than a dog that lives in your 72 degree home. Heck, a short coated dog that lives outside in the cold is going to be better able to handle the cold than a long haired breed that lives mainly in the house.
I'd make sure the dogs have some small shelter to go into from the wind. A 'Dog-gloo' is perfect IMHO. You want something with the entrance facing south to keep the wind out, and something small enough that a dog or two will quickly fill it with their body heat. A Dog-gloo heated by a pair of plott hounds is probably better than being in the garage.
dogloo
that plus a flap for a door and some carpet remnants or blanket or straw on the bottom and your dogs are going to be set for even the coldest weather.