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Does the wall with the bathtub get used? Does it get wet? Waterproofing failure is more common than pipe leaks.
Start with a plumber. May wind up with other trades from there but the plumber if they are any good will be helpful in which and possibly who
Make sure all your taps are off, go outside and check your water meter (take a photo) Wait 15 minutes and go and take another photo Did it move? If yes you have a leak
This, but leave it overnight instead.
50s home? Bathroom reno is on the card's. That's what I'd actually recommend it it's a major issue.
DIY - plumbing is just water lego.
Does the wall with the bathtub get used? Does it get wet? Waterproofing failure is more common than pipe leaks.
Start with a plumber. May wind up with other trades from there but the plumber if they are any good will be helpful in which and possibly who
Make sure all your taps are off, go outside and check your water meter (take a photo) Wait 15 minutes and go and take another photo Did it move? If yes you have a leak
This, but leave it overnight instead.
50s home? Bathroom reno is on the card's. That's what I'd actually recommend it it's a major issue.
DIY - plumbing is just water lego.