I can remember way back when I was just a wee lad, my dad going to the local lumber store and constructing our irish setter a custom made dog house from scratch. Made from drawn out sketches, the accommodations inside were spacious enough for our rambunctious cone-headed flame red pooch and a small child to all fit inside...
These days, it seems dog houses aren't as common with many pets, small and large, kept indoors. But if I was a dog owner, I think I'd follow my father's footsteps and build something similar to these unique doghouses from Sustainable Pet Design, which incorporate a rooftop garden into the house plans.
These dog homes consists of a roof structure with a growth medium, filter membrane, a drainage layer, and waterproof coating so Fido doesn't get wet inside his Green Roof home. Sustainable Pet Design
even recommends collecting the water filtered from the roof for drinking water for your pet, but this might only be advisable in certain non-polluted regions.
Some of these designs are pretty unique and difficult in shape/finished to easily emulate. But there are plenty of resources to make your own design from an assortment of plans online
of much simpler plans, including your own Sod Roof doghouse
very similar to the Greenrrroof designs.