Condensation how do I deal with it?

Question

I have had double glazing and loft insulation in my house, the damp proof course has been checked and is ok but now I have damp patches half way up my walls what do I do. Are there any devices other than a standard dehumidifier that I can use.

Answer 1

In Britain it is part of the building regs. that double glazing comes with internal vents. The only way to cure condensation is to ventilate.

Answer 2

Basically you don't have air circulating and the room is sweating.

A short term solution - simply open a window.

You need some form of ventilation so the room can breathe.

Answer 3

Lots of ventilation.

Answer 4

I would expect that you did not have this problem before the insulation went into place.  Insulation also requires ventilation.  The space that it is installed into cannot be completely packed and should have a moisture barrier between the living space and the insulation space.  This is especially true in cases of cathedral ceilings.  Moisture rises in the house and will go through the walls especially if the vapor barrier is incomplete.  Once in the insulation space it will gently be removed if there is a space above the insulation with ventilation.  If there is no space or if the ventilation is limited it will condense on the underside of the roof and then drip back into the house.  This will tend to cause some damage to the ceiling and walls and might be confused with condensation coming directly from the room.  

The solution is a vapor barrier below and ventilation above the insulation that is not packed in too tightly.   The need for ventilation is one important reason why you often see ventilation devices on the top of our houses.

Answer 5

Sometimes double glazing is so tight it cuts out  ventilation. All houses need ventilation, since merely breathing generates moisture vapour. The there is in the moisture vapour generated in the bathroom and kitchen. In quantities we are talking a condensate production  in litres. You normally would need  at a minimum of 4 air changer per hour. Have an extraction system fitted, put lids on pans when cooking, keep the kitchen door shut, open your windows. Incidentally when you wake up in the morning is there condensation on your bedroom window. If there is is then its the moisture vapour for the rooms occupants. If there is no condensation you got the windows open or there is another way air changes are occurring.