A doghouse should protect your animal from the elements and keep him warm. Use weatherproof plywood exterior panels to build the outside walls. Then insulate the walls, floor and ceiling with 1.5 inch Styrofoam sheets. For inside paneling, use hardboard or similar material. Paint the doghouse black.
Black doghouses absorb heat and stay warmer in winter.
Make sure the doghouse is portable. You might not want the doghouse to sit in the same spot during the winter as it does during the summer. With a moveable doghouse, you can protect your dog from the effects of sun, shade and wind. Elevate the doghouse on bricks or cement blocks to keep the floor dry, but don't forget to insulate the floor as well. You might want to get house design plans before starting to build your doghouse.