damp internal wall

[dad40otter]

hi i live in a old house (200 yrs ) in one of the upstairs bed rooms on the wall ( gable end)at this time of the year i keep getting wet patches ,like someones just wiped it down with a wet clothe,not all over just in patches ,can anyone please give me some advice

[raysparx1]

Is there a chimney on the gable end? if there is it could be that the flashings need attention, if you do not have a chimney the damp is either seeping through the rendering or brickwork, if it is brickwork, you could coat the wall with a waterproofer like "thomsons water seal" if it is the rendering, it will need looking at by a builder, good luck, Ray

[The Builder]

...as Ray has said....it could be a number of things............impossible to tell from here I'm afraid :o)
Not likely to be anything major though.............best to just get someone reputable to look at it for you