Condensation on internal wall of downstairs toilet

[king.inter]

Hello all,

I have a condensation problem on the walls in the downstairs toilet. From what I can gather the previous owners converted this toilet from an outside storage area. It is brick built & attached to the house, the 2 walls that have condensation on are both external & single skin. The roof on this is flat felt, there is two air vents in there which are closed. It has a small double glazed window. One thing I will say is, that this toilet is REALLY cold. One last thing dare I say it... We use the room next to it to dry clothes on a couple of clothes horses. Is this such a bad idea as everyone say?

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[topbanana]

firstly most things which are cold on one side and warm on the other will have condensation on the warm side. think of those lovely old windows we all had which were drenched if you managed to stop the draughts throthem and were lucky enough to have some form of heating.
even though you say its cold in there,i bet its colder outside.
2. drying clothes will create dampnessin the air and could add to the problem. if i do it i try tokeep a window open to create a balance.
number 1 is the major prob id say. you need to create a cavity wall inside or out, to regs to cure this.