What important factors should I consider when building a dog house?
I usually build people houses, but have built a dog house or two.  My research says that the size should be adjusted to the size of dog. It wants to be just big enough for the dog to lay down stretched out, and not too tall. A raised insulated floor is good. The reason for this is that the only heat source is the dog's body heat and too big a house will be too cold in winter.  Of course, it should be insulated and have a safe sheathing on the interior to cover the insulation. It should also have some type of flap door that the dog can easily pass through, but will reasonably seal the opening from the elements. I have seen several books with designs and decors for your pet's condo at building materials stores and book stores online. Don't forget to put it's name on a plaque over the door!

PS: If the weather is really bad, let the poor thing indoors, have a heart.