Condensation?? (merged threads)

webwalker

IWantToBeFree wrote: »

Woke up this morning to the sound of dripping in the bedroom, was the condensation from the window gathering on the ledge and then running down the walls...

The upstairs windows in the house ALWAYS have condensation on them, its becoming to be a real problem as its leading to wet walls and also mould.

What could be causing the condensation and whats the best way to tackle the problem? My dad seems to think its due the house being too well insulated...

Are the windows single glazed? If so thats your problem.

IWantToBeFree_2

No they are double glazed.

richardw

If you are getting condensation on double galzed windows then look at the ventilation situation which may need improving.

ariba10

Warm air holds a lot of water. Cold air holds very little.

When the warm moist air cools, on reaching a cold surface it condenses out as water.

You either have to have a colder surface for it condense out on (A dehumidifier) or you change the air by ventilation.

27col

While I can understand that mechanical ventilation can remove damp air. I do not see how opening a window in a room can do any more than let in cold air at night. There is no reason to suppose that the air in the room is more likely to flow out than it is, that the air outside will flow in.
The answer is not ventilation, it is insulation, and some heat to keep the fabric of the house warm. Coupled with taking steps to reduce the amount of condensation produced. One of these ways is to use a bath mixer tap and not having steaming hot water flowing into the bath, before it is cooled by adding cold water. If it is mixed in the tap, then the resulting bath water has virtually no steam coming off it. Unless you like really hot baths. It took me quite a while to discover this, but now I get only the slightest film of condensation on the mirror.
I do not get condensation so I can only assume that I am doing something right.
I have just this week increased the roof insulation from100mm to 250mm. This is not against condensation but simply to keep the gas bill under control.
I could not disagree more with the opinion of dougk about the 'green' approach to heat losses.
I do appreciate the problems that people in old and /or rented accommodation can have, but I know what works for me.
By the way, I forgot to mention that as my bathroom does not have a window, it has a fair sized extractor fan which runs all the time that the room is being used. I suppose that this bears out my earlier comment about mechanical ventilation.

colin13

having thick curtains does not help,, this stops the heat getting to ur window,, there fore causes condensation,,but as u say a quick wipe in morning or leaving window slighty open will help a great deal

27col

I refer you to the merged condensation thread. I certainly don't think that you can have too much insulation. However, if there is not much heat going into the building then, the insulation will not be doing very much. Obviously, it can stop heat loss, but any if there is some heat to lose.

webwalker

27col wrote: »

While I can understand that mechanical ventilation can remove damp air. I do not see how opening a window in a room can do any more than let in cold air at night. There is no reason to suppose that the air in the room is more likely to flow out than it is, that the air outside will flow in.

Both happen, the warm damp air flows out and the cooler drier air flows in which when heated can hold more moisture and flow out again. Mechanical ventilation does the same thing only quicker, if the air isn't replaced you die and the air lives outside in the cold lol.

27col

For anyone who might be interested, and going on the number of post on this thread, I imagine that is a lot of people. I have just Googled, " reasons for condensation". I recommend it to all posters. There is a wealth of information available, have a look.