I've just had a new window put in the bathroom and there are white patches appearing between the double glazing...this appears and then disappears. Is this the silica that hasn't been removed properly and is it partly due to condensation and improve sealing?

Alison, October 2008

You have a failed unit which means the actual double glazed glass unit has a broken seal, most units are guaranteed for 5 years so contact the company who fitted your windows and request a replacement.

Evolution Window Repairs

evolutionwindowrepairs.co.uk, November 2008