How to protect sill plate from water when slab is bigger than the structure sitting on it?

Question

I am building a small garage extension. I want the walls in plane with the existing walls, but the existing slab in this area extends 3" beyond where the sill plate will sit.

What is the proper way to deal with this? I was going to use pressure-treated lumber for the sill plate with a sill gasket underneath and caulk the edge. I was thinking of creating a small sloped curb out of stucco and lathe to help move water away from the sill. Or maybe I could use flashing but that would be ugly and possibly sharp.

I haven't been able to find what the "correct" solution for this scenario is.

Answer 1

Not sure if this is "correct", but one solution would be to lay one course of block underneath the sill plate. This would keep the plate plenty high above the concrete. You would probably still want to slightly taper the outer edge of the slab away from the building, to avoid water sitting there and seeping in through the block.