by spinynorman »
Fri Sep 17, 2010 4:08 pm
We have a brick-lined well outside, in a courtyard, which we also covered with a thick glass plate. The well is dry and is ventilated, with an old drain inlet at the top on one side and a narrower pipe we put in on the other side to try to create an airflow across the glass. It still gets covered with condensation.
I bought anti-condensation self-adhesive sheet (the sort used for shop windows or greenhouses, but that didn't work at all.
Shaving foam, the cheap white stuff, not gel, works for about 2 weeks - the water forms a film across the glass which you can see through and on a warm day it quickly evaporates. For several weeks after that, condensation forms, but doesn't obscure the glass. To apply the foam, squirt a little on a cloth and rub all over the inside of the glass, until it is clear again. A little goes a long way.
I haven't tried the heater idea. The problem would be where to put it so it doesn't spoil the look of the well. An expensive alternative would be to replace the glass with an iron grating.