Filling Gap between sill plate and slab
I'm working on building a new shower. I have a knee wall that is on top of a slab. There is about a 1/4" gap between the sill plate and slab that runs for about 6 inches or so. I would like to fill this but am not sure what to use. i am more concerned about it being structural ok then with stopping any air flow etc.
I will be creating my own mortar bed for the shower. Can i simply just "push" some dry pack under here when I put down the morter bed?
Are there any other suggestions? Maybe some cement patch?