1. Dear Mat, yes the owner of the flat above is liable for the entering of water from his flat into your flat. Essentially, this water constitutes a nuisance in law and both an owner and an occupier of property is liable for the emission of water from their flat premises into an adjoining flat or the flat below. It does not matter how the emission of water occurred. Here, the flat owner is liable for the water from his washing machine entering your flat and causing damage to your ceiling. The flat owner is also liable for all other damage caused by the water. It makes no difference that there is only ground rent payable. The principles are the same. So here, you should contact the flat owner and seek recompense for the damage.
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