No insulation (and no space for it) = damp

MouldyOldDough

in_my_wellies said:

My house has this sort of roof. The blurb called it 'galleried ceilings', it's 1908.
When we moved in in 1883 the ceilings were black with mould in 4 of the bedrooms, mostly behind 1950's style hardboard built-in wardrobes. 
We striped out the wardrobes and installed an airbrick in each bedroom and the problem has never returned even in the rooms which are largely unheated. I thought the airbricks would be drafty but TBH I don't even notice them now

We still have airbricks in each room but they make no difference
We also use an electrical dehumidifier every time that we have a shower

ThisIsWeird

Photo, MOD?

GDB2222

MouldyOldDough said:

in_my_wellies said:

My house has this sort of roof. The blurb called it 'galleried ceilings', it's 1908.
When we moved in in 1883 the ceilings were black with mould in 4 of the bedrooms, mostly behind 1950's style hardboard built-in wardrobes. 
We striped out the wardrobes and installed an airbrick in each bedroom and the problem has never returned even in the rooms which are largely unheated. I thought the airbricks would be drafty but TBH I don't even notice them now

We still have airbricks in each room but they make no difference
We also use an electrical dehumidifier every time that we have a shower

Are you saying that you get damp on the ceiling/walls after it rains?  How about when it's cold and dry?

MouldyOldDough

GDB2222 said:

MouldyOldDough said:

in_my_wellies said:

My house has this sort of roof. The blurb called it 'galleried ceilings', it's 1908.
When we moved in in 1883 the ceilings were black with mould in 4 of the bedrooms, mostly behind 1950's style hardboard built-in wardrobes. 
We striped out the wardrobes and installed an airbrick in each bedroom and the problem has never returned even in the rooms which are largely unheated. I thought the airbricks would be drafty but TBH I don't even notice them now

We still have airbricks in each room but they make no difference
We also use an electrical dehumidifier every time that we have a shower

Are you saying that you get damp on the ceiling/walls after it rains?  How about when it's cold and dry?

No - we get condensation on the ceiling on the outside 2 or 3 feet when it is cold - the roof itself is fine

I never mentioned rain...

ThisIsWeird

Insulated p'board, applied directly to the underside of your sloping roof = cure.

GDB2222

MouldyOldDough said:

GDB2222 said:

MouldyOldDough said:

in_my_wellies said:

My house has this sort of roof. The blurb called it 'galleried ceilings', it's 1908.
When we moved in in 1883 the ceilings were black with mould in 4 of the bedrooms, mostly behind 1950's style hardboard built-in wardrobes. 
We striped out the wardrobes and installed an airbrick in each bedroom and the problem has never returned even in the rooms which are largely unheated. I thought the airbricks would be drafty but TBH I don't even notice them now

We still have airbricks in each room but they make no difference
We also use an electrical dehumidifier every time that we have a shower

Are you saying that you get damp on the ceiling/walls after it rains?  How about when it's cold and dry?

No - we get condensation on the ceiling on the outside 2 or 3 feet when it is cold - the roof itself is fine

I never mentioned rain...

Ah, you said: "We also use an electrical dehumidifier every time that we have a shower", and I misunderstood what you meant!

MouldyOldDough

GDB2222 said:

MouldyOldDough said:

GDB2222 said:

MouldyOldDough said:

in_my_wellies said:

My house has this sort of roof. The blurb called it 'galleried ceilings', it's 1908.
When we moved in in 1883 the ceilings were black with mould in 4 of the bedrooms, mostly behind 1950's style hardboard built-in wardrobes. 
We striped out the wardrobes and installed an airbrick in each bedroom and the problem has never returned even in the rooms which are largely unheated. I thought the airbricks would be drafty but TBH I don't even notice them now

We still have airbricks in each room but they make no difference
We also use an electrical dehumidifier every time that we have a shower

Are you saying that you get damp on the ceiling/walls after it rains?  How about when it's cold and dry?

No - we get condensation on the ceiling on the outside 2 or 3 feet when it is cold - the roof itself is fine

I never mentioned rain...

Ah, you said: "We also use an electrical dehumidifier every time that we have a shower", and I misunderstood that!

Ha Ha - no I meant a shower in the bathroom !!

MouldyOldDough

@Doozergirl

@ThisIsWeird

Here are photos of the mould, showing the sloping ceiling - with no insulation (or space for insulation) above the sloping bit.. the mould lines up with beams above

As can be seen - an airbrick

ian1246

As others have said... insulated plasterboard is the answer.

Basically any moisture in your room is condensing on the coldest surface - the sloping bit, causing the mold.

By insulating it, it ll be less cold & therefore less condensation/mould. Remove the existing plaster & plaaterboard, apply new insulated plasterboard - you'll loose a few inches in height but should solve the problem.

Make sure the insulated plasterboard has a vapour barrier so no vapour gets through to the timber of the roof - and tape the edges of the plasterboard etc... to where it joins the rest of the ceiling/wall to maintain the vapour barrier.

MouldyOldDough

ian1246 said:

As others have said... insulated plasterboard is the answer.

Basically any moisture in your room is condensing on the coldest surface - the sloping bit, causing the mold.

By insulating it, it ll be less cold & therefore less condensation/mould. Remove the existing plaster, apply new insulated plasterboard - you'll loose a few inches in height but should solve the problem.

You mean on the inside of the ceiling ?