From: B-P Golden Oldies: "Is this the list with all the ivy haters?"
[mailto:[log in to unmask]]On Behalf Of John Leeke,
Sent: Thursday, April 27, 2006 10:33 AM


Leland:

I'd be concerned of cases where foam insulation installed in stud walls 
forces all the vapor migration through the wall, to pass through the 
studs, overloading the studs with moisture causing decay in the studs. 
I've seen two case where it looks like that was happening, though we did 
not have the budget to investigate and prove it.


John Leeke, American Preservationeer


>
John:

Can you sketch in what the conditions might have been to cause this problem such as 50% RH in the space, general or specific outdoor climate (your neck of the woods?), general wall constuction (drywall, poly vapor barrier (or none), 2/4 studs with closed cell foam between (cavities well filled?), outer moisture plane, then vinyl siding, etc. or was this information to be determined by the further study?  Any macro or micro climate issues such as being close to the ocean, wind-driven rain, bad downspouts, etc.

Do you think the stud-rot problem could be solved by using a poly vapor barrier under the drywall?  Would the screws to secure the drywall present too many penetrations of the vapor barrier (or would they be tight enough to not be a problem)?


Bruce

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