If you are in the market for a hot tub look at Arctic Spas, They are mfg'd in Canada and designed specifically for cold weather climates, best insulated tub on the market. They have a self supporting hull, meaning you could take the fiberglass tub completely out of the enclosure, set it on the ground and fill it with water. They also have an available option called a forever floor which is completely impervious to water, insects, rodents, & rot. I own the Timber Wolf model and it is great! For more info click:
www.arcticspas.com.