Getting rid of Damp

baegan

I have a problem with damp in my house (<10 years old)
It occurs in black patches in my windows
(back windows, upstairs bedroom and bathroom
and on my front windows downstairs)
around the edge where the wall meets the window.

I have cleaned off the black patches only for it to reappear a few days later
I have checked all the obvious stuff, leaks etc
and the house is heated by gas and its on quiet a bit, but not excessively
The house also gets aired out

Any thoughts?

pipers

Check to see if your heating system is pitching.

for more info look here

scroll halfway down the page

Cal

The house also gets aired out

But does it have adequate permanent ventilation? Are you running an open gas fire? Is this mould only forming on the windows? Have you single or double glaze?

Not saying I have the answers but more info may isolate the issue.


Cal

Fudger

Is the front of the house North or South facing?

Silicate Gel bags might be a short term solution. They basically absorb damp/water that is in the air. If you put them on your window ledge it may help a bit. There are also silicate based paints, the link below is to 'industrial paints' but if you ask in a hardware/DIY place they should be able to help you with some sort of 'silicate based internal paints' that are available. I never had to buy the stuff myself so i can't say exactly where but they should be available its a pretty common problem.

The link below will give you an idea of what its can be used for

http://www.techno-preneur.net/timeis/apctd2/silicate.htm

baegan

thanks for the replies

some queries answered

Is the front of the house North or South facing? front facing eastwards

Does it have adequate permanent ventilation? windows opened a little every day

Are you running an open gas fire? no

Is this mould only forming on the windows? i have noticed some on at the air vent in the bedroom also

Have you single or double glaze?double glazed windows

Victor

Originally posted by baegan
I have a problem with damp in my house (<10 years old)

Do you have "Homebond" or some similar guarantee? It sounds like the jambs of the windows are a "cold bridge" where there is inadequate insulation. As this is then the coldest surface in the room, any condensation will occur there. Depending on the design / construction of the window jamb, you could strip of the plaster and fit insulation. It would however appear that you are producing a lot of moisture inside the house or that the moisture produced has no means of escape. Especially in the bathroom, make sure it is adequately vented after people use it for showers and baths.

Originally posted by baegan
It occurs in black patches in my windows. I have cleaned off the black patches only for it to reappear a few days later I have checked all the obvious stuff, leaks etc

It sounds like mould. Most moulds need moisture and a particular temperature to grow. When you clean it off, use a cloth in some diluted bleach (use cold water and gloves). This should inhibit the growth, but doesn't solve the problem.

Originally posted by baegan
and the house is heated by gas and its on quiet a bit, but not excessively

Are you happy that the boiler vents to the outside adequately? There should be at least one air vent in the boiler room in addition to the flue / exhaust.