Posted by Harry on August 10, 2006, 7:00 pm
There are two solutions to condensation problems. Condensation is
caused by warm miost air being cooled to its dew point.
So you can ventilate as already said. Ie extract fan in kitchen and
bathroom to get rid of moisture generated by showering/bathing/cooking.
This is where most moisture comes from. Don't forget air has to be
allowed to come in to replace what you've extracted.
Or you can isulate the area where condensation is occurring. The
insulation will have to be non-vapour permeable. However this could
just transferr the problem to elsewhere.
You will need a fungicide to kill the mould. It's hard to get rid of
once established. Srtong bleach is quite good, but smelly. Or you could
go out and buy the proper stuff.
A de-humidifier will certainly work but ventilation is cheaper to buy
Jeff Palmer wrote:
Posted by daestrom on August 12, 2006, 3:06 pm
The one thing that all the 'venilation advocates' have to keep in mind, is
that basement temperatures, and humidity levels vary around the
In my area for example, my basement usually is about 60 - 65F in the summer.
This makes it a nice place to 'hide' during the heat of the day. But in
July, the dewpoint has routinely been over 70F, even at night. Under those
conditions, ventilating would just aggravate the problem by bringing in more
As Nick has said, it is desirable to keep the RH below 60% to avoid
problems. To keep the RH that low in a 65F basement, the incoming air needs
to have a dew-point of 51F or lower.
Before going down the 'ventilation' road too far, figure out what the
basement temperature is and look up 60% RH at that temperature on a
psychrometric chart. Then read off the dew-point for that condition. If
the dew-point of the outside air is often higher than that, then you might
re-think the whole ventilation idea.