Hi everyone,
Looks like a great forum!
Basically In one of the outbuildings on my house, I have a bathroom with a brick outside wall, without a cavity. Previously I have had a water leak from the roof which has lead to the plasterboard and polystrene insulation behind it becoming very soggy and creating black mould. I have now stripped the wall back to the brick and have fixed the water ingress and it seems to be ok. I think there could also be condensation developing to some extent however. Do you have any recommendations of products which I could apply to the bare wall to try and avoid the walls going mouldy when they are redecorated? Also what type of insulation do you recommend between the brick and the plasterboard?
Sorry for the long post, but any help will be much appreciated!
Newbie here, please help with damp proofing question!
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leebwk
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Hi 117,
solid brick walls in bathrooms can often be problem areas firstly you need to keep the area well ventilated and make sure you have a good extractor fan fitted ie 150mm so it removes condensation when the bathroom is in use also it does help to keep the windows open on vent all year round.
secondly ther really isn't anything on the market that will prevent black mould forming as this is down to condensation and air flow so eradicate that and you should be ok.
Thirdly i like to use celotex or kingspan as insulation beneath p/board.
Hope this helps
solid brick walls in bathrooms can often be problem areas firstly you need to keep the area well ventilated and make sure you have a good extractor fan fitted ie 150mm so it removes condensation when the bathroom is in use also it does help to keep the windows open on vent all year round.
secondly ther really isn't anything on the market that will prevent black mould forming as this is down to condensation and air flow so eradicate that and you should be ok.
Thirdly i like to use celotex or kingspan as insulation beneath p/board.
Hope this helps
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Stoday
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Houses that were built in the past with 9" brick walls were perfectly satisfactory in the conditions of yesteryear.
Then, there was no central heating nor draught-proofing. You'd light a fire every day in the winter and that would draw lots of air from outside to ventilate the house. Fires would warm the air somewhat, which would make it able to absorb moisture, which would then be sucked up the chimney. You'd have a bath in a tin bath in front of a fire, even in summer, otherwise you wouldn't have any hot water.
Today these houses have central heating, and are draught-proofed. It's the lack of ventilation that's causing a problem which was not envisaged when the house was built.
Then, there was no central heating nor draught-proofing. You'd light a fire every day in the winter and that would draw lots of air from outside to ventilate the house. Fires would warm the air somewhat, which would make it able to absorb moisture, which would then be sucked up the chimney. You'd have a bath in a tin bath in front of a fire, even in summer, otherwise you wouldn't have any hot water.
Today these houses have central heating, and are draught-proofed. It's the lack of ventilation that's causing a problem which was not envisaged when the house was built.
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Perry525
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please help with damp proofing question!
117,
You have cured the leak, but the wall is still damp and cold!
As long as its cold any humidity in the room will diffuse into it.
The first thing is to get the wall dry.
If you raise the temperature of the room, the water vapour in the wall will move outwards, moving towards the cold outside.
The worst thing you can do is let the temperature of the room drop, a drop in temperature will cause the moisture in the air to condense into the wall.
Installing waterproof cladding on the outside, with a two inch or more gap between it and the wall will stop the rain from soaking the wall and will enable air to circulate upwards, this dry air will then absorb some of the moisture.
Once the wall is dry, insulate on the inside, with at least two inches of polystyrene direct to the wall, cover with a waterproof plastic sheet, seal all gaps and holes and plaster over.
Perry
You have cured the leak, but the wall is still damp and cold!
As long as its cold any humidity in the room will diffuse into it.
The first thing is to get the wall dry.
If you raise the temperature of the room, the water vapour in the wall will move outwards, moving towards the cold outside.
The worst thing you can do is let the temperature of the room drop, a drop in temperature will cause the moisture in the air to condense into the wall.
Installing waterproof cladding on the outside, with a two inch or more gap between it and the wall will stop the rain from soaking the wall and will enable air to circulate upwards, this dry air will then absorb some of the moisture.
Once the wall is dry, insulate on the inside, with at least two inches of polystyrene direct to the wall, cover with a waterproof plastic sheet, seal all gaps and holes and plaster over.
Perry