On Sep 23, 5:31*pm, "Hugo wrote:
"Any original filling has been lost and replaced by air many
times over long before the condensation became visible."

I am looking at making a set of patio doors - but I don't like the idea of
sealed DG units that will probably or definitely go off in 5 years time or
even less.. didn't windows used to last for a century?

I was thinking of installing two panes of toughened glass to each door as
with a DG unit, but with the panes not sealed. The interior facing pane on
its own frame with spacer fixings. This would be to give ventilation between
the panes to reduce condensation, but be able to close them up tight when it
gets really cold during the winter. Are there reasons why this wouldn't work?

url:http://myreader.co.uk/msg/1391145585.aspx


air exchange would result in condensation. That would rot a timber
frame, if used, and require regular wiping.

The way to solve this is to vent the space to the outside rather than
inside, then no condensation occurs. Maybe use a plug of 9:1 sand and
cement to keep insects etc out


NT