Is your Dog House Legal?
The law requires provision of "sufficient" shelter in order to maintain an animal in a state of good health.
Use hard plastic or painted wood (metal rusts and conducts heat and cold). Make sure it does not leak and it faces south in winter, north in summer.
Raise the house off the ground several inches.
Put a flap over the door (old rug or rubber mat with strips cut vertically).
The roof should extend 8" over the door to help keep the rain out.
Use straw, newspaper or cedar shavings for bedding; nail a strip of wood at the bottom of the doghouse door to keep them from spilling out. Don't use rags or rugs, they absorb water and can freeze.
Put water in a sturdy, tip resistant bowl or bucket inside a rubber tire to prevent tipping, and check for freezing several times a day during winter.
Humane Society of the United States
Mich. Dept. of Agriculture Animal Health