My tub/shower combo in the basement has a gap at the top for floating slab considerations. The rest of the walls have a gap at the bottom, but the tub needs to sit on the concrete. Anyway, If solid pipes are used and the floor does shift up or down, the pipes would have problems.

Can I use flexible copper connectors (like those used with water heaters), or any other type of flexible hose? I'm not sure what flex pipe sections can be sealed up in the wall...

Thanks