With building damage the other party is liable if they are negligent but otherwise not.
There was a tail in the press a few years ago about a little old lady without insurance. Her neighbours chimney fell down through her roof. She couldn't afford to fix her roof and next door were not liable.
If I drove a car into your bedroom and smashed it to pieces, you'd go and speak to your insurer?
I mean, I guess that's a thing, but I'm going to start with the cunts upstairs that caused the damage first.