clothes getting damp near ext wall

Hi

I have all my clothes near an external wall, its touching the wall, and my clothes have become damp. does anyone know why?

thanks

//www.diynot.com/wiki/building:condensation_in_houses

Open windows regularly, and crank the heating for an hour in the evening to 'drive out' the dampness.

This isn't a basement wall is it?

no,

its 1st floor bay window. we dont have ventilation in the room.

thanks

move them away from the wall simples

done that already.


i think i need to have ventlation put it in. where would i put that? On the external wall, one high level and one low level?

Any trickle vents/slot vents at the top of the window frame? Keep them open, otherwise just open the window for a bit every day.

Hi

Your problem is being caused by condensation/thermal bridging. Adding ventilation to the room is unlikely to help your situation as the relationship is between the clothes and the temperature of the external wall within the built-in wardrobe.

The problem is caused by warm moisture laden air (warm air holds more moisture than cold air, and when the warm air is cooled the air can reach dew point where its becomes saturated and deposits as either surface and/or interstitial condensation. In your situation the clothes are still in a sufficiently close proximity to the external wall to be cold enough to become affected by condensation.

The solution is double barrelled: 1. Use a PIR insulated panel to the affected wall/s, insulation thickness would need to be a minimum of 25mm and in combination increase the room temperature in order that the temperature within the wardrobe is kept above the dewpoint of the air. Add high and low ventilation grilles to the wardrobe to encourage the circulation of warm air.

If your pockets are deep enough you should consider removing the wardrobe in its entirety and cladding all the external facing walls, given the intruisive nature of this work it would be reommended that the minimum thickness of PIR insulation should be around 50mm BUT you will need a PIR with plasterboard finish which either adds or takes away 12.5mm from the overall thickness. And refitting the wardrobe - you will still need ventilation to the wardrobe in order to retain the temperature within the wardrobel above its dew point.

Others may have alternative remedies, but the above thread should at least make you aware of the nature of the problem, which is half of the battle!

Regards

alittlerespect said:

Adding ventilation to the room is unlikely to help your situation

Click to expand...

I'm not so sure about that. Ventilation will drop the moisture content in the room air closer to that outside and should reduce condensation. I suggest leaving a large ventilation gap (50mm is often used in building structures) between large furniture (or even a rack of clothes) and external walls.

You need to keep the plaster temperature above dew point to prevent damaging condensation. This requires both heating (to raise the plaster temperature) and ventilation (to lower the dew point).

A trickle vent on a double glazed window is one option. A single room vent through the wall is another and is usually about 300mm below the ceiling. Opening windows also helps; I think the Swiss traditionally opened their windows after they got up and aired their duvets over the window sill. In a bedroom, you need to get rid of moisture that builds up overnight.