Re: GBlist: condensation question

["mac12" <tomthomas@uswest.net>]

KG,

   This is a very common occurrence.  It seems to me that the degree of 
condensation depends on 3 things, the relative humidity of the room, the 
temperature of the inside glass surface relative to the room and the 
amount of air passing over the glass surface (affects relative 
temperature and provides opportunity for evaporation of condensation.

Closing curtains affects the latter two factors.  The curtains insulate 
the glass surface from the room, allowing a greater temperature 
difference.  They do not isolate the window from the humidity present in 
the room however, so moisture can migrate from the room to the window to 
replace that which has condensed.  Also, by restricting air movement 
over the glass, the closed curtains retard evaporation.

Tom Thomas
Macurco, Inc.
"Gas Detection"



KG wrote:

> Greetings One and All,
> 
> When my double-glazed windows are uncovered (no curtains), I see very little
> condensation.  When the curtains are closed, however, I see more -- even if
> the air feels dry.  I've been using the window condensation as a rough
> guide to when I should turn on the ventilation fans, but now I'm wondering if
> that's such a good idea.  Why do I get more condensation when the curtains
> are closed?
> 
> Thanks for your thoughts and for the stimulating reading!
> 
> Kevin Giansante
> Veliko Turnovo, Bulgaria  
> 
> 

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