Completely understand this issue as we're undergoing it as well in our (rented) newbuild townhouse. Thankfully it was under Builders Warranty. hey first fixed it over 6 months, finishing July 2022. They said it was a leak from the A/C. So when we started to use the A/C again in December, it started again, only heavier.
The upstairs kids bathroom had the ceiling and back of toilet cut out to find the pipes and found the leak from a pipe which has been “fixed” - although I question the efficacy of the fix
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Then they re-cut the ceiling downstairs to find the leak “highways”
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One of them is the fan/light which has filled with water both times. Will be replaced again as it has siezed.
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