Re: Attic Condensation
Some things come to mind --- while placing the rigid foam on the attic side of the knee wall is a good idea to increaase the insulation performance with a continious thermal break , I'm thinking the 1/2 inch isn't really much benifit. I would recommend at least 1 inch or more.
Originally Posted by Kansas Farmer
The rigid foam itself does have an acceptable air permance value but it's the seam joints that unless are sealed will leak air.
The insulation in the 2X6 rafters --- R21 is designed to fill that spacing however, you have the vent chutes that set back from the roof sheathing 1 inch which means you have a void in the ceiling insulation. If the vent chutes extend into the attic space this void will have a negative impact of that ceiling insulation by allowing moving air within the insulation --- which is not good.
The North side is not benifiting from solar heating as the South side does. The solar heat gain creates more active convective air currents which also helps with carrying the moisture out.
Also. depending on what spaces are below on the North side ( like a bathroom ) --- if there are any penetrations from plumbing stack vents , electrical , etc., that aren't properly air sealed --- these could be causing more moist warm air netering the attic and condensing on that side.
"" an ounce of perception -- a pound of obscure "