Roofs and Foundations Revisited

Revisited with new knowledge: A home inspector/engineer told me while we were discussing the viability of a roof structure in Dallas near Mesquite in the vicinity of the Dallas Athletic Club, that the expansive clay used around the foundation acts as a seal to keep water from infiltrating under the home. So watering your foundation does help to keep the flood out during a drought. If the builder placed soil is kept moist the rainwater can't seep under the house in droves (water droves?). The foundation ventilation needs of a pier and beam foundation are similar to a roof's but slabs work on a system of near constant moisture underneath to keep the slab firm and constant.
I still maintain you really don't want your yard contracting and a dry yard might interfere with the natural migration and equalization forces of nature. The famous law of averages makes moisture and heat move to the nearest location where they are in lesser quantity. A dry yard must have some effect on the dirt under your home.
I wouldn't take a chance.
Another foundation nemesis is the dying/drying root. Sure roots can lift a building. But they'll try to take the path of least resistance to where they want to go until forced to rip the steel and concrete structure apart for the water they know is under your home. The conundrum is that not watering your foundation, which is not necessary if you water your yard, breaks the expansive soil protection and when the forty days and nights come, or just ten might do it, you'll get a pool under your home.
Years later, after the killer root who broke your home's base has met the end of its life cycle, the decay of this giant forbidding behemoth of power that lifted your home a half inch will start to return to dust. You know the dust left after you burn a big chunk of wood that might composed .005% of volume.
Welcome to Carlsbad Caverns, or is it Inner Space?
As the world turns and spins around Sol, this departed organic matter allows your home to settle up to a foot. You see, the root has buddies. Millions of them, from capillary size to the thigh of Lou Ferrigno during his prime after he pumped up or maybe double or triple that along side all the others, that could theoretically make up half the fill under the northwest corner of your home.
You'll never hear "crack" or "boom" but you'll feel the pain when you try to sell your home and the foundation, sheet rock, plumbing, roof, and structure of your home needs to be rebuilt before any mortgage or insurance company will touch it.
If you can't bring yourself to torch it, turn it into a rental and don't give the renters their deposit back. They might torch it for you I've heard.
www.jonwrightroofing.com