Damp on in living room wall possible from Gas meter box Damp can be a major issue in the home. Find answers to questions or post your own here.

[linton149]

Hi Guys,

Over the xmas break I noticed a patch of damp the size of a human head on one of our living room walls.

I have indentified that this patch is exactly on the opposite side of the gas meter box outside.

I have had a little look and cant see how damp is getting in as the gas box is dry and there seems to be some putty on the pipe that comes into the house.

The patch gets worse when we have been cooking and it starts dripping down the wall but the next morning when the heating is off the wall has dried.

Intererstingly the kitchen seems to be perfectly fine when cooking.

Any ideas on how I should proceed?

Thanks in advance!
Mark

[Stelf]

The fact that the damp patch is opposite the external gas meter is a little suspicious. If the hole which the gas supply goes through has been made good with putty I would scrape it out and fill the hole in with a mix of quick setting cement, usually better than ordinary cement for making waterproof, and building sand. You can get this mixture in ready mixed small bags from DIY stores.
Best wishes

[the specialist]

Hi - the fact that you notice this damp patch whilst cooking (which incidentally is a time when you are producing more moisture) and then it dries up again by morning would indicate that it is a condensation problem. At the moment it is very cold outside. I am presuming that the gas meter box is recessed into the wall. This means that there is a cold spot behind the cupboard - that is to say the cold spot is inside the house behind the cupboard. Cold spot means in relation to the area surrounding it.
Ok so how do you cure it? The best solution is to try and remove the excess moisture to the outside whilst you are cooking. Do you have an extractor in the kitchen?

From the way you describe the damp patch it is not water penetration which would also take longer to dry out. Next time you observe this problem take note of the weather.

Hope this helps.

Aidan

[linton149]

[quote="the specialist"]Hi - the fact that you notice this damp patch whilst cooking (which incidentally is a time when you are producing more moisture) and then it dries up again by morning would indicate that it is a condensation problem. At the moment it is very cold outside. I am presuming that the gas meter box is recessed into the wall. This means that there is a cold spot behind the cupboard - that is to say the cold spot is inside the house behind the cupboard. Cold spot means in relation to the area surrounding it.
Ok so how do you cure it? The best solution is to try and remove the excess moisture to the outside whilst you are cooking. Do you have an extractor in the kitchen?

From the way you describe the damp patch it is not water penetration which would also take longer to dry out. Next time you observe this problem take note of the weather.

Hope this helps.

Aidan[/quote]

Hi Aidan,

What you say makes perfect sense.

Its not wet outside when I notice the problem however it is very cold and the problem only occurs after the heating has been on for a few hours.

The gas box is recessed into the wall which im guessing is why the area feels colder than the rest of the wall in the living room.

Last night I noticed the patch after about 3 hours of the central heating being on but we didint cook so im guessing thats why the problem wasnt as bad at it normally is.

I have had a look in the gas box and they have packed it with bubble wrap in an effort to dry and "warm the wall"?

If the problem is steming from the difference in outside vs inside temperature on the specific wall spot causing condensation how should i proceed, insulation in the gas box etc or do I need to pack the cavity behind gas box with something?

Thanks all again
Mark[quote][/quote]

[the specialist]

Hi again. Yes if you can insulate behind the meter box do it. But beware if the rest of the cavity is uninsulated you could cause another problem. If the only insulation is one specific point it naturally has a top. If any rainwater penetrates the outer leaf it could run down the inner face of the outer wall and may track across the insulation which will act like a bridge. Ideally you would either fill all the cavity or introduce a cavity tray above the insulation - tricky one.

Aidan

[Stelf]

Hello again,
Re my last post I must confess I had not considered the fact that the gas meter would be recessed into the wall in which case I agree totally with the reply from Aidan that the problem is almost certainly condensation. Well done Aidan. If it is possible to pack the gap between the meter and the wall with suitable insulating material I would do so, perhaps some polystyrene sheeting but don't let it bridge the damp proof course.
Best wishes.

[the specialist]

Thanks stelf.

I am a timber and damp specialist so I may have an advantage over you. I am 50 this year so also very experienced, although, I must confess I am still learning.

Aidan

[TheDoctor5]

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