We moved into a detached property which is about 30 years old nearly 3 years ago. The moment we moved in and started putting stuff up into the loft it stank a horrible musky smell. I recently got the Christmas decorations out from the loft (before the snow) and it was its usual musky smell with slight wetness on the loft ladders. Went to put the decorations back in the loft water was dripping everywhere from the felt. Having looked a bit closely and what I initally thought was ice on the felt was infact a white mould. I can advise we have 2 brick air vents, either side of the house, it has the normal amount of insulation with a few old pieces of wood so we can rest items on for storage. The insulation does not go right up to the eves, there is ventilation in the facias, there are no down lights or extractor fans. A roofer has been to have a look and says the felt is ok and is fitted correctly. I've checked the pipes from the airing cupboard to the loft are sealed and they are ok. The reserve hot water tank for the heating I've checked and thats not hot. The only thing I can see is a very slight gap in the loft hatch which I can't believe is the cause of such condensation. Oh and we dry our clothes indoors but not on the radiators and use a dehumidifier. For it to be that smelly I'd imagine this is happening every year, but this is the first time we've ever witnessed it. I know we're not alone but what else could the problem be and how can we stop it happening again? Hope someone can help.

DIYClare, January 2010

Our loft condensates only when snow sits on the roof,2nd year on the trot,any reason why the snow is causing this?

mouldy, December 2010

May be of use
http://www.projects.toolvolt.co.uk/listing.php?id=001

But make sure the vents are clear in the soffit and that thay do go right throu into loft and not there just for decoration.

If you have small round vents in your soffit that are right throu, then increase the amount, manufactures recommend every 200mm all the way round. Which equates to a 20mm slot vent all the way round.

If you have a high pitch roof, fit 2 tiles two thirds the way up on all sides of the roof.

www.toolvolt.co.uk, February 2010

ensure that there is a cross-flow roof eaves ventilation front to rear and make sure all loft hatches are properly sealed so no heat escapes to loft area from floor below.

jaan, January 2010

you need to fit some ventilation in your loft area either at the edges or with vent tiles. If your roof has had under felt fitted this will agrivate the condition because the ventilation has been stopped. if this problem is not fixed your woodwork will all rot. the same problem happens in bathrooms or kitchens unless there is a ventilation vent or fan fitted. hope this helps Terry

Terry Howell Manchester, January 2010

i have the same happin 2 me now the loft is very cold and keeps dripping and mouldy and the rooms below r damp and mouldy but i been told wash it with bleach and it keeps comin back

dean, January 2010

You need to check and make sure that the vents are clear, builders cheat some times.

des, January 2010

had this once, had to bin everything in loft all ruined. somebody had insulated loft and covered the cavities with insulation so air not circulating. this in turn led to whole house being damp. packed up and left after that.

ste, January 2010