Is there a law that the bathroom can't be enlarged and reduced?

There are laws, although there is no express provision in the law. And the property should also disagree:

What the property here should think of is: the problem of load-bearing wall, the problem of waterproofing, the problem of complaints next door, and the problem of pipes. These problems are very troublesome. There is no relevant provision in the law, but the load-bearing wall must not be moved, so it is estimated that your business is hanging by a thread. The only way is: write a relevant guarantee responsibility letter to the property, and make it clear that it is not their responsibility. I guess so.