Originally Posted by
Jerry Peck
Stuart,
One thing you did not define (or I missed it).
The room the water heater is in, is its floor raised or at garage level?
If the floor is at garage level, the water heater will need to be raised.
If the floor is raised, it 'might' be okay, depending on 'how high' the floor is raised - the ignition source (lowest flame or spark) needs to be 18" above the 'garage floor', so it might be okay if there is a 9" step and the burner is 9" above the raised floor (both unlikely).
The floor isn't raised. The slab for the garage and the "closet" look like 2 different pours. The garage floor is about 9" inside the door/wall and has a curb that is about 1/2" high and 1-1/2" wide. The inside slab is below the top of the curb about an inch making it a little below the garage floor.
The whole thing looks like it could be a "fix" to a design error (shown in wrong place), installer error ( put in wrong place), or "Stupid" error and maybe was a compromise to make the AHJ happy enough to let the builder finish. A hot housing market here in 2002 and very overloaded building inspectors. A lot of incompetent builders around then and unfortunately, they're still here.