Not sure if this should be here or in the property thread.
DH owns a ground floor flat in a two flat house which he lets out to tenants. The problem is with the upstairs flat - every few weeks or so there is leak that drips (or pours) into his flat, causing quite a lot of water damage and disruption to his own tenants.
Whenever there is a leak, DH or his tenants contacts the upstairs landlord's mate, who is dealing with the property. The mate says he sends someone round to fix it but it has happened about 6 or 7 times now so either he doesn't actually send someone round or whoever does go round can't fix it or does a bit of botch job that doesn't address the problem properly.
It's so frustrating for DH, he's even managed to get his plumbers to go upstairs to have a look. They said the whole shower/bathroom was a bit of a mess, and it wasn't clear what the problem was because everything was really damp and shoddy and needed proper investment/replacing.
There is a shared freehold between the two flats, but DH isn't even sure who owns the upstairs anymore, as we think it's changed ownership since DH bought the downstairs. He struggled to upstairs owner to pay his share of the insurance, and I think he's now given up and just pays it all himself (DH, that is).
From a legal point of view, is there anything he can do to get the upstairs landlord to fix the problem properly, pay for the water damage and possibly even compensate DH for lost rent. (DH gave his tenants a discount on rent for a month because of the hassle they've had).
Was hoping for some of the usual brilliant mumsnetter advice, (and justify to DH why I spend so much time on here )