Hi!
I live on the 2nd floor and my neighbor from 5th floor had his sink pipe burst and flooded all 4 appartements bellow. Since I am in the lowest appartement and have wood floors, it affected me the most. All the floor is damaged. I do not have insurance and neither has she. The leak was big and we called 911 to the rescue. My building has sent some blowers to dry the walls and the floors, however the damage is there. Nobody seems to be responsible, and now I have to pay for replacing my floors. Is there any help for me in this situation? It is not my fault but now I have to pay from my pocket?

It is the landlord's responsibility to pay for the floors unless you own your unit. I would also suggest renter's insurance. It will not cover the unit, but will cover your belongings, so if this happens again and ruins something that's of value to you the insurance company will replace it. I pay $8 a month for renter's insurance.

Like CM said, if you don't own the apartment and are just renting, your landlord is the one who must replace your floors. If the floors were there when you moved in, he must replace the flooring. If you put the flooring down, then you are the one to replace the flooring.

Unless the 5th floor occupant was negligent to the point where they caused the stoppage, the building owner is responsible for repairs.

I don't see any clear info where you rent or own. Additional details would make my answer more to the point. If you own do you have a mortgage?

Whether the OP rents or owns, insurance would help in this situation. Because even if it's not your fault, the insurance can get your damages repaired first and go after the other person for repayment. Seeing that it was a situation where a pipe suddenly burst and no one is truly at fault, the landlord's insurance should cover the structure of the building. You should have your own insurance in place to cover your personal belongings (furniture, clothing, etc.) as the landlord will not be held responsible for replacing your things. As CM said, renter's insurance is very cheap and a worthwhile investment because of the number of things that can happen outside of your control.