Home is slab on grade, no evidence of post tensioning, nor any existing cracks in drywall.
We need to remodel the master bathroom. There is an existing garden tub and an adjacent shower stall.
We would like to remove both the tub & shower, and convert it to a large roll-in shower.
One contractor wants to cut out a 39" x 89" section of the slab, excavate a few inches, move the drains, then pour concrete into the opening, so that the top of the sunken area would be a few inches lower than the existing slab. He claims he will use rebar to anchor the new "sunken" area slab to the existing slab. He then wants to use a prefab, pre-sloped, pan which he will drop into the sunken area, with the entrance area at the level of the existing slab.
Then based on using Schluter Kerdi for the walls, extend the kerdi over the prefab pan, with 2x2 tile over.
The long dimension of the cut would be parallel to the exterior wall, and about 7'6" from the edge of the slab.
Other contractors advise against cutting the slab as they say it could lead to major cracking of the main slab in the future. They say that cutting the rebar that's in the floor is not a good idea. They also say it would be difficult to prevent leaks where the main slab meets the sunken area. Basically, they don't want future liability for slab damage.
:confused: What say you all? Is it acceptable to cut the section out or should we look for a better plan, possibly doing away with the roll-in concept and using a conventional curb?
Thanks in advance.