Water Damage - Is this considered tenant responsibility?

[Jon A.]

Hello everyone, I'm looking to get some advice on this situation with a tenant in my property. 

I own a condo unit and this tenant has been living there for a few months now. Soon after they moved in, they asked me if I can replace a faucet handle in the bathroom because it was hard to turn on/off. I did not have any issue using it before they moved in and so I told them the replacement wouldn't be needed. The tenant asked me if I could get a material to fix the issue using a lifetime warranty I had, so I did and they received it not too long after.

The issue happened when they decided to replace the handle by themselves. They told me they had shut down the water first (I had told them how to when they moved in, in case if they needed to do,) but apparently it did not shut off the water pipe that was connected to the faucet. They called me when the water started to leak and it took a few hours to have a plumber come in and stopped the leak. The incident caused damages on walls in my unit and a unit below.

The tenant has a renter's insurance so it covered the damage unit below mine, but it did not cover for my unit.

In order to fix the walls it required a partial demolition, drying process, and restoration. In total it's almost $20k.

I believe my tenant should be responsible for the cost because the incident happened when they tried to fix the faucet without getting a professional's help. However the tenant thinks I should use my property insurance for structural repairs, that I should have offered to fix the faucet at the first place that it was supposed to be a landlord's responsibility.

Would you please share your thoughts and advices please? The bathroom has not been restored yet and it's been a few months the tenant has not been able to use it (they have another bathroom to use in the unit, at least.) I really appreciate for your time and help.