Damp Patch - Suggestions?

[SadieLovatt]

Hi,

We have recently moved things around in our main bedroom and noticed a damp patch on one of the walls. This is a 1st floor room in a two floor house and the patch is towards the lower left corner as you look at the window in the room. Currently the patch is not very big, less than the size of a carrier bag and roughly the size of the what was in that corner. Obviously we don't want it to get any bigger and the chances are that it has been caused by sleeping with the windows and door closed. ie we believe it has been caused by something internal.

Anyway, we've started leaving the window open slightly each night but is there a simple solution to clear up what has already amassed. ie is it a simply case of stripping the wallpaper, coating the wall with something then re-wallpapering? and if so... what exactly?

Sadie.

 

[JohnD]

Damp patches in bedrooms are usually caused by condensation, especially if they are inside or behind furniture placed against an outside wall.

I think when you say "the size of the what was in that corner. " you might mean there used to be furniture or something against the wall, and this is typical of condensation. If you ventilate it well it should dry out with no stripping or redecoration required.

//www.diynot.com/wiki/building:condensation_in_houses

however if it is under a window, look for any sign of rain penetration round ther frame.

 

[Deluks]

Used to get this in our small spare bedroom.
Our dg windows have no 'proper' trickle vents, rather the 'slightly open' option handle. Leave this window slightly ajar now, permanently, and rad is on the lowest setting. Prob solved.

 

[SadieLovatt]

In our old house this we had something similar and there were black patches (mould I assume) as well - lets face it, you generally dont see whats behind a wardrobe until you move it and therefore won't see the problem develop.

We never really got around to treating this properly as we only noticed it just as we were about to sell the house.

Just to put everything into context, am I right in assuming that this is just an extension of just being damp? and if so, should that happen again, would we need to do anything different (ie is that the stage that we would need to treat the walls and redecorate)?

Sadie.

 

[JohnD]

In case of condensation, ventilate. If that doesn't cure it, ventilate some more

If you have had it in two homes, then probably your lifestyle and domestic habits are causing it.

Never drape wet washing around the house or over radiators. If you do, the house will always be damp and no-one can help you.

Read this link:
//www.diynot.com/wiki/building:condensation_in_houses

 

[SadieLovatt]

...If you have had it in two homes, then probably your lifestyle and domestic habits are causing it....

Yep, you're probably right and that's why I am insisting that the upstairs windows are opened slightly during the day - something that wasn't always happening, especially at our old house and all washing (bar tights, socks etc.,) are put in the tumble dryer.

But, there are always times in which you don't ventilate enough and something happens in an area that you don't always see or a room that you don't go in often.

So, if we did get mould, ventilating is not going to get rid of it (I assume) so what should be done at that stage?

Sadie.

 

[JohnD]

no wet washing

extractor fans in bathroom and kitchen

that's the major sources dealt with.

Then ventilate.

Many modern window frames have trickle vents, but if not, you can add them by drilling holes.

 

[SadieLovatt]

...and that gets rid of the mould?

 

[JohnD]

the mould depends on damp to grow. stop the damp and it will stop growing, then you can use bleach and clean it off.

clean it without curing the damp, and it will come back again and again.

 

[noseall]

...and that gets rid of the mould?

Not always entirely.

The other thing to consider is removing the potential for condensation to form upon cold surfaces.

This can only be achieved by insulating the wall in question.

 

[SadieLovatt]

...This can only be achieved by insulating the wall in question.

Something I have been looking at but as we have a 1930s solid wall house, and the rooms aren't that big then it narrows our options.

Sadie

 

[^woody^]

You need to define if this is a damp patch (yellow stain) or a patch of black mould

By the sounds of it, you have had something by the wall, which was blocking air flow around an already cold bit of wall, and this has allowed a small area of condensation to settle and form subsequent mould

If you can more things around to keep this area of wall exposed, then it may correct itself ... but you will need to treat the existing mould with some fungicide and if the wall is papered, remove this too as mould feeds of the old paste

Even with additional ventilation in these older houses, a cold wall, blocked by an item in the room will always be susceptible to condensation problems. So look at the room arrangement before considering extra ventilation

 

[SadieLovatt]

...Many modern window frames have trickle vents, but if not, you can add them by drilling holes.

Obviously I don't want to damage the windows and so made some enquiries about the latter point earlier.

Out of 20 or so companies I contacted, only 3 were prepared to do this. The others (that I managed to get through to) said that this was not something that they did and a good proportion of these cited the reason of being that some dg windows have reinforced frames which would make life difficult as well as make a messy job.

Sadie.

 

[JohnD]

true. Opinions differ about how difficult or easy it is.

 

[noseall]

Fitting trickle vents retrospectively can be a nightmare.

It is possible to ruin a perfectly good window for the sake of a £20 trickle vent.