Mould in 3 bedrooms

nickbaker66

I live in a semi-detached house and the 3 bedrooms upstairs that face the outside walls have white mould not the dark black stuff over the walls i have cleaned it with bleach but it just keeps coming, its not so bad in the summer but the winter it's worse which then gets in the wardrobes and all sorts

So i am after some advise really -

The windows in 1 of the bedroom's are really old they are wood frame double glazed windows that have a lot of condensation on which i try to wipe up as best i can.

In bedroom 1 it has a 600mm high radiator by 900mm wide, the size of the is room is approx 13ft by 14ft with brand new windows (not much condensation on them) or mould on that wall but the side wall collects a lot of mould.

In bedroom 2 it has a 600mm high radiator by 1200mm wide, but this room as a stud wall in it to create 2 bedrooms the window wall (old windows soon to be replaced in Jan) has spots of mould on it but

In bedroom 3 it has no radiator loads of mould in the corners of the room, each side of window wall (again old windows soon to be replaced in Jan) and the external side wall as well has loads over it.

sorry to drag on, now my question is once i have the new windows installed if i put a bigger radiator on the external wall's in bedroom 1 & 3 will that keep the wall's warm in the cold weather and stop mould spores collecting on the wall or put plasterboard on both side wall's so it does not get too cold or both radiator & plasterboard in both rooms or maybe another solution

i am stuck for answers on this issue and its really getting me & my wife down.... Thanks for reading

Nick

muckybutt

Could well be dry rot if its white in colour, have you peeled back some of the wall paper in the effected areas to see if its behind there as well ?

nickbaker66

yeah i did and i did not see any just the plaster

themacster

It could be efflorescence caused by soluble salts contained within the plaster coming to the surface when the plaster is damp and the later evaporating leaving the crystallised salts (the white "mould") on the surface. Check to see if the wall is getting damp from the outside due to leaking eaves gutters or other defect.

Would be worth checking in the loft to be sure there is no dry rot in the timbers just to be sure.

ariba10

Could be condensation. Have a read of this.

http://www.harfordsonline.com/downloads/condensation%20info.pdf

nickbaker66

i ve checked the guttering just to be sure and thats all clear ill have a look in the loft tonight thanks

nickbaker66

thanks ariba10 thats a good read.... putting a radiator on that external wall would stop the moisture settling and cooling on the wall what do you reckon ? and maybe a re-plaster as well

themacster

Is the mould a powdery crystalline substance that brushes off with your hands (efflorescence) or is it a softer organic matter?

ariba10

nickbaker66 wrote: »

thanks ariba10 thats a good read.... putting a radiator on that external wall would stop the moisture settling and cooling on the wall what do you reckon ? and maybe a re-plaster as well

I would make sure I had cured the problem before I had it re-plastered.

nickbaker66

themacster wrote: »

Is the mould a powdery crystalline substance that brushes off with your hands (efflorescence) or is it a softer organic matter?

its more like a white dust but if i leave it a while it starts to turn a yellowish

themacster

It really sounds like efflorescence to me, in which case its caused by damp walls. What are the walls made of and how old is the house? If its a solid wall, has the pointing between the bricks perished allowing the wall to get saturated when it rains? If render, maybe its cracked or not adhering properly allowing water behind it to get trapped and soak into the wall.

If its a cavity wall, you really shouldn't be getting damp wall problems inside unless the wall was poorly constructed and the cavity has been bridged. Are there any similar issues in other rooms with external walls (I'm assuming its the external walls that have the "mould" problem, though internal ones could suffer if water soaks through to where they abut the external walls)?

I don't think condensation will get the wall wet enough to cause efflorescence - with condensation what you get is usually black mould. Interstitial condensation is where the water vapour penetrates the wall from inside the house and then condenses within the thickness of the wall as it reaches its dewpoint - it is possible this is the cause but it shouldn't cause as much of a problem as you appear to have. Are the walls painted or papered?

You need to find out why the walls are getting wet, cure the cause, then dry the wall out - the efflorescence will then stop.