Remodel vs. repair bathroom slab on grade
I have been a long time lurker to this forum and have always found great advice from different perspectives. I like the "DIY" philosophy but there are times when I am happy to pay the premium for someones knowledge and experience. I just need a starting point. Here is my problem.
My southern California (near Disneyland) single story home has a "moist" area next to the slab. Even on dry days there is a area butting up to the outside of my slab (about 24" wide and spreads out onto the yard) that stays wet. The bathroom is near this wet spot, but about 3 feet over. There is no evidence of moisture in the bathroom (silverfish, though) or next to the bathroom in any direction. My copper feed pipes were re-routed to the attic years ago.
I stopped using the bathroom 3 days ago and the wet area immediately started drying out. I think I have a sewer leak under a on-grade concrete slab floor.
My wife said "We want to remodel and move the bathtub as well as the sink. Why not just break out the slab and have a plumber re-pipe and repair any problems."
It makes sense, I do want to move the bathtub and that will entail breaking out the slab in order to put in a new p-trap. I have to tear the bathroom down to the studs in order to re-pipe, run electrical, and prepare for the tile. Why not?
The bathroom is TINY! 68" by 99".
I called a local remodel contractor (a carpenter) and another (a tile installer) and both said "no problem, we move drains all the time". The quoted me a total remodel cost of around $15,000
Problem is, neither one of them is a plumber. And I believe I need to solve my drain issue before picking out tile or deciding on what kind of pocket door I want.
I spoke with a concrete cutting contractor, he said "If you tear the bathroom down to the studs and eliminate any plumbing protrusions, I will cut the whole floor out up to 3" from the floor plates. I will also haul away the concrete. I can do it for $900. You can call in your plumber to fix your problems and re-pipe for your remodel."
I guess I would still need to get another concrete contractor out to lay a new slab after the plumber is done.
I would like to ask the experts in this forum. Am I going in the right direction?
I know I should call in a master class plumber for advice, and I will. I am trying to combine the below-slab repair with the remodel relocation of plumbing drains and save me some costs. Is cutting out the ENTIRE floor dangerous? Or is it a reasonable alternative?
Any suggestions would be greatly appreciated.