Help! Damp appearing on ceilings and wall

Amerie

I bought a house last year. The bedroom I sleep in is always cold but with no noticeable condensation etc. It does have a vent but also has two external walls. In the join of the external walls the is black mouldy looking stuff forming and the whole way down the wall to the floor. I washed it off but now it has come back. Can anyone tell me how this can be treated? The walls are not insulated and the house is over 25 years old. It has double glazed windows and some attic insulation. We had a surveyor/engineer come out and do up a report before we bought the house and he checked the walls with a little device and said there was no dampness. I don't even know who I get to look at the problem... a builder or who?

...Yes I am a woman but I do alot of DIY and because this could be a major problem I didn't want to attack the problem myself in case it worsens. Any help would be appreciated.

mynameis..

I have the same problem so am interested to hear replies, you may need to insulate the walls are they cavity walls?

donaghs

Could the gutters be clogged, and are leaking lots of water onto the exterior wall when it rains?
I've a bit of damp forming in one of walls every so often. Came back after cleaning it off, and painting it. I assumed it was the gutters overflowing, just had them cleaned. Hope it helps, to early to say yet.

mynameis..

hi donagh, what made you think of this? is it easy to clean or do i need a professional? are your walls insulated?

Dexterm99

Amerie wrote: »

I bought a house last year. The bedroom I sleep in is always cold but with no noticeable condensation etc. It does have a vent but also has two external walls. In the join of the external walls the is black mouldy looking stuff forming and the whole way down the wall to the floor. I washed it off but now it has come back. Can anyone tell me how this can be treated? The walls are not insulated and the house is over 25 years old. It has double glazed windows and some attic insulation. We had a surveyor/engineer come out and do up a report before we bought the house and he checked the walls with a little device and said there was no dampness. I don't even know who I get to look at the problem... a builder or who?

...Yes I am a woman but I do alot of DIY and because this could be a major problem I didn't want to attack the problem myself in case it worsens. Any help would be appreciated.

Are there any cracks on the outside of the joining walls? Is the mould worse at the top or bottom of the join? Is the bedroom part of an extension?
If it's not the guttering that was already mentioned, I'd get the surveyor back out because it sounds like he didn't notice a potential structural defect.
Exposure to mould will make you really sick. You need to get this fixed soon.

Amerie

There are no visable cracks on either wall but the walls are dashed so maybe they are not visable? The bedroom wasn't part of an extension. They are cavity block built walls with no insulation. I don't see the point in getting insulation put in when there is damp. I thought of the gutters alright but can't get to it. I'll try get the hubby out this weekend. I'll have to scrub the ceiling and walls and probably paint it. The mould seems to be worse on the bottom.

I'll try clear the gutters and clean off the mould... then if it returns then I'll get after the surveyor for sure.

Thanks btw for all the replies.

dubtom

I know you said there is a vent in the room but is it open.Do you open windows every day to vent the room. I know this seems obvious,but you would be surprised at how many people have 'damp' problems which are due to lack of fresh air. Only last week I sent in a tradesman to a property to fix a damp problem and it turned out they had the vents blocked with cloths and never opened a window. You could smell the dampness,but yet the walls are insulated and there is no leaks,it should be the first thing you check.

Amerie

The vent is open and I've tried leaving the window open but it doesn't seem to work very well.... justs makes the room unbearable (cold wise). But I'll give anything a go at this stage!

ART6

If the mould is in the corner of the adjoining walls and is all the way down, then water is getting in at that point, and almost certainly at the top (water is controlled by gravity and goes downwards!). It's unlikely that it is getting across the cavity between the outer and inner walls unless the builders left some mortar or rubble in there to do that (and you would have known that well before 25 years). Gutters are normally clear of the walls by the soffit boards, so even if they overflow they will not so wet the outer wall to the extent that water can migrate through to the inner across the cavity.

Since the room is a corner, then I guess the roof above is not a gable end but has a sloping tiling in two directions -- one slope to wall A and one slope to wall B. Where the two slopes join they do so with ridge tiles (the half round thingies), and if the mortar under those has failed then it can let water through inside the cavity. There should be roof felt underneath them to stop that, but the felt used under roof tiles 25 years ago was often cheap crap (sorry!) and it is known to leak.

The first check I would do would be to look at the ridge tiles and see if the mortar is missing in places, and then to go into the attic and look at the liner and see if it's got any holes in it. If it has, buy some thick bitumen mastic from your DIY store and trowel it over the hole.

Oh, and definitely send yer man up the ladder but don't tell him I said so:D

RKQ

It could be a leak but it sounds like condensation.
Moist warm air condensating on a cold uninsulated external wall.

Black mould forming in the external corner of a room, at ceiling level and slowly working its way down. Is it dry "dusty" black / grey in colour?
Try a dehumidifier to see if that improves the problem - if it does then consider dry-lining the wall internally. There are SEI grants to help with this work. Also increase ventilation.

Is the corner of the wall north or north east facing?
Is there an en-suite in this bedroom?

donaghs

We decided to pay a guy to clean and paint our gutters. It's a 2-storey former Dublin Corporation house in a terrace. No problem doing it yourself if you have a tall enough ladder and feel confident.

Not 100% sure that this was the cause of the damp patches on my walls, but it was a job that needed to be done anyway.

Amerie

The corner is east facing just about and the roof goes in a V shape on the whole house and it's the end of the roof in the corner where the damp is showing (if that makes sense)....

It is the black/ grey dusty type mouldy damp... It seems to be spreading over the ceiling now along the wall... it's wrecking my head...