are your windows realy draughty if so where from,as prob could be anything from the silicone sealent around your windows or gasket on sashes not making a seal or your hinges have broke and not pulling sash in far enough, also might not be your windows as water could be coming through bad brickwork or hanging tiles if you have them on your house or through the roof of your house and moisture settling on your cold window panes.to check if its your windows,seal around all your sashes and around your windows onto plaster with marsking tape and see if it gets any better,if its just the same i think it one of the other probs mentioned.if need to ask anything e-mail me through contact page on website if you need a fast response.hope this helps
shaun www.sdwupvcrepair.co.uk
February 2008