Crack in plaster board and dampness

tevion

My bedroom at the front of the house (6 year old terraced house) has a crack in the wall just above the left side of the window and goes to the ceiling, where there is mold/dampness forming.
The mold runs along the length of the ceiling edge above the window.
The room is kept ventilated, and the mold cleaned off regularly, but keeps returning.
The right side of the window also has a smaller crack on the wall, that also goes close to the ceiling.
I have attached a picture, which shows the plaster board splitting, and continuing up to the ceiling where the mold is.
Is this a major problem, or how can this be sorted?

beyondpassive

Tevion,

Can you tap the plaster or plasterboard on either side of the cracks, just see if it sounds different.

The surface temperature is below dew point where the mould is forming, this is likely to be due to having a cold bridge above the window. The wall is likely facing north. See by tapping on it, if you can determine what materials are used, can you take a pricture of the outside.

I test a lot of buildings for defects, most of the defects that are surfacing are buildings between 3 and 8 years old. Your problem is typical for celtic tiger era buildings. Our construction industry and regulators never address the issue of surface condensation risk due to cold bridging. Many builders are still building to this standard. Being a contractor must be the only job you don't need any qualification for. Its nuts that one off house builders build to minimum standards with no conception of what problems they will encounter in the short term.

tevion

beyondpassive wrote: »

Tevion,

Can you tap the plaster or plasterboard on either side of the cracks, just see if it sounds different.

The surface temperature is below dew point where the mould is forming, this is likely to be due to having a cold bridge above the window. The wall is likely facing north. See by tapping on it, if you can determine what materials are used, can you take a pricture of the outside.

I test a lot of buildings for defects, most of the defects that are surfacing are buildings between 3 and 8 years old. Your problem is typical for celtic tiger era buildings. Our construction industry and regulators never address the issue of surface condensation risk due to cold bridging. Many builders are still building to this standard. Being a contractor must be the only job you don't need any qualification for. Its nuts that one off house builders build to minimum standards with no conception of what problems they will encounter in the short term.

Yes the wall is facing North alright.
I will do a tapping test and take a picture of the outside of the wall too.
Thanks for your help

tevion

Did the tapping test, about 3 inches to the left of the bigger crack, it sounds hollow, and it doesnt sound hollow to the right of the crack and all along the area above the window.
As far as i know, it is just plaster board on the inside walls and it is tape and joint, the walls are not skimmed.
I took 2 pictures from outside as well, I just noticed there is a crack on the external wall too that I hadnt noticed before.
Another thing I just noticed, the vent on the external wall, doesnt go through to the internal wall, maybe this is normal..

beyondpassive

Sorry Tevion I'm stumped. I could guess it is a ring beam over the window, but then the crack would be about 4 or 6 inhes left of the window reveal. The vent is very odd indeed it should go through to the room.
Is one of the vents for the neighbouring bedrooms?
Is there a flatpack duct running to am ensuite? unlikely but I'd like to rule it out.
How deep is the window from the inside face of the plaster on the inside,
Is it hollowblock with plasterboard lining?

Also have you a drill?
If you dont want to go the destructive testing route, I can get a thermal imaging camera to have a look if we have someone in the area. what corner of the country are you in?

sinnerboy

I see a lot of growth in the gutter ( looking closely ) . The top of the facia board behind the gutter is badly stained . So I would suspect your gutter is clogged and now an imperfection in the sarking membrane ( above rafters, below tiles ) is at last being found out - i.e. resulting in a "slow" leak

The crack in the plaster is probably a joint in the plasterboard failing now with the damp conditions causing the gypsum to swell and therfore strain the joint . Notice that the crack is in compression not tension ( pushing together not pulling apart )

So hire an insured maintenance guy to clean the gutters . And local to the problem - push back some tiles .

Lets know whats you find ( vicariously , of course don't get up there yourself )


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