This is a brand new door/double glazing installed two weeks ago.
This morning there was condesation/dew on the outside of one glazing unit but not on the other (or any others in the house) – this may mean something or nothing. Is this unit faulty or are the rest duff??

you sure the condensation was on the outside not in the central void?

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Nice garden. You need to clear up those leaves though, else you may end up with too much moss.

[/obligatory]

If it is on the outside I suppose it means that that pane of glass is colder than the other, causing the water to condense.

One is cleaner than the other or has some sort of dressing on it.

Defo on the outside.
Should have been up earlier sorting lawn and leaves… sorry
Windows where cleaned yesterday. Actually Mrs SB was grumbling that the window cleaners didn’t do a very good job and went out with the spray to do it herself – maybe she only did one sde!

Condensation will be forming on the colder bit of glass – so if the warmth is coming from the inside of the room then the misted glass is in the glazing unit that’s giving the better insulation. If they’re supposed to be Argon filled (which is used to improve the insulation) then it could be that one has been filled properly, and the other not.

It might also be simply down to one of the panels being warmer because its been in the sun more than the other which might have been in shade ?

Is there a sniffer vent above the LH door open? I get condensation like that if I leave certain vents open overnight.