ᐅ Missing waterproofing in bathrooms discovered after 16 years.

Hello dear forum members,

During the renovation of our basement, we discovered that the bathroom in the basement was missing waterproofing — both underneath and on the walls. This is now being properly installed.
At the same time, I am wondering what has been done about the bathrooms on the upper floor and the toilet on the ground floor.
Water would drip from one of the bathrooms on the upper floor into the hallway below after using the shower (cross-laminated timber ceiling). So I assume no waterproofing was applied there either. Only the silicone seal prevented water damage so far, but it was no longer perfect and we recently redid it.
Well, the house was built over 16 years ago with a general contractor who went bankrupt shortly after. So there is no warranty anymore.
What are our options now? Replace everything at our own cost, or is there any liability on the part of the tile installer, even though it was done through a general contractor? I still need to review the construction specifications in detail, but if waterproofing was state of the art back then, I don’t understand why it wasn’t applied here.
I really don’t want a legal dispute. We just don’t want to bear all the costs ourselves and want a proper installation so that no more water can penetrate the timber house.
Sorry if I have not provided enough details. I’m a bit overwhelmed at the moment and I’m happy to answer further questions. However, I would really appreciate avoiding any negative remarks, which I’m sure you understand.
Thanks in advance for all the helpful answers.
Good luck, Alena

Ibdk14 schrieb:
Well, the house was built over 16 years ago with a general contractor who went bankrupt shortly afterward. So there is no longer any warranty.

That already gives you your answer. Unfortunately, you will have to pay out of your own pocket, as there is no one left to hold accountable.

No leverage; the costs are your responsibility.

Okay, that was somewhat expected.

But is it actually advisable to renovate the bathrooms on the upper floor as well, or can they be left as they are since they somehow worked without waterproofing? I’m reluctant to undertake the work, but now knowing that water could be accumulating somewhere, I can’t feel completely at ease either.

I realize as I’m writing this that none of you can really give me a definite answer. We’ll have to make the decision ourselves.
Thanks anyway for your quick responses.

Where should the water in the bathroom come from?

Ibdk14 schrieb:
Water was already dripping from a bathroom on the upper floor into the hallway of the ground floor after using the shower (cross-laminated timber ceiling). So I assume no waterproofing was applied here either. Only the silicone seal prevented further leakage so far. It was no longer perfect, so we redone it ourselves.

I’m not an expert in this field, but if everything is already damp and you apply waterproofing now, where will the moisture go? How long was everything slightly leaking before you even noticed the damage? It’s possible that it feels sealed now, but mold might already be unstoppable.

You need a skilled contractor to inspect the situation on site.