Re: [GBlist] Re: Big Green: Radiant Floor Heating

[Norbert Senf <mheat@mha-net.org>]

At 01:08 PM 2001-10-26 -0400, Mike Rogers wrote:
>(snip).  The physics says moisture wants to flow from hot to cold, so 
>moisture in the slab will what to flow from the warm slab through the 
>semipermeable insulation to the cold ground.  Poly would prevent this 
>flow. (snip)

and

At 03:23 PM 2001-10-26 -0400, Frazer Dougherty wrote:
>(snip)
>  and since moisture vapor flows from warm to cold, isn't poly, possibly 
> as Lstiburek says, 'counterproductive' ??

Heat flows from hot to cold. Vapor (gas) diffuses from regions of high 
concentration to regions of low concentration. Vapor can also be 
transported by gas flow.

Why does moisture flow from warm to cold?

Curious ........ Norbert



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