I am a landlord and my tenant has told me there is damp in the upstairs bedroom and now has appeared  in the living room what could course this? How to fix it?

get some one out to locate the cause,could be any number of reasons. lack of proper ventilation, bad pointing ,roof,windows,leaking gutter. without looking at the problem it is impossible to say what is the cause.

it cud be your gutters are back filling or blocked and the water is working it way down the wall. if its in your living room damp wont go more than meter and a bit high. or if you want go to b an q for a damp tester there about 10 pound hope this helps e mckeown

Gutters / downpipe blocked causing overflow onto porous masonry. Water entering cavity wall. Never underestimate poor ventilation and inadequate heating. One of my tenants complained of mould on a north facing 1st floor wall that has never had problems before. It was due to them drying damp clothes in the room with no windows open and window trickle vents closed. Buildings must be able to breathe.