I purchased a 4 year old house in Washington State that was built with one corner 2 1/2 inches higher than the other 3 corners. The house is built on a steep hill with a stair-cased foundation that is flat and level, but the pony walls between the foundation and house were built uneven. There are pony walls of varying heights under three sides of the house, and two of them ramp up to a high corner in the back. Each subsequent 2x6 stud outward from the high corner is 1/8 inch shorter than the next. I believe the moron who framed the house marked the length of each stud with the one he just cut, which subtracts off an 1/8th inch of saw kerf each time (i.e., blade thickness).
Is it possible to lower the high corner by cutting the pony wall studs down appropriately, or is a framed house stiff enough to remain cantilevered up without ever dropping?
The entire back wall needs to be lowered across its full 30 foot length, but the adjacent side wall only needs to be lowered out about 17 feet from its corner. I've considered relieving the weight of the house from the pony wall studs with screw jacks placed between each stud. Then detach the siding and wafer board from the sill plate and cut the bottom of the studs down as needed. But would the house come down by lowering the screw jacks a little each day? With the bottoms of the studs removed the house would no longer be tied into the foundation until it dropped back down far enough to toe nail the studs and wafer board back into the sill plate. Is there any chance of it falling over while unsecured from the foundation?
I'm concerned that the shear strength of the waver board tied into the wall studs all the way up from the crawl space to the attic two floor above might act like a torque box and resist lowering. But if the house drops 2 1/2 inches will the cement based siding all crack off, or just the drywall if I'm lucky? Any concerns with windows along those walls?
Perhaps an easier way to level the house is to lay a new layer of sub floor over the existing, with custom taper shims directly over the floor joists. But this would be a bandaid and require cutting off the bottoms of doors, raising toilets, etc.