Rigid foam insulation over Bildrite during remodel/reside?
I have a recurring question / situation that comes up in my east central MN location (6b-7a border). There are many 1970's homes undergoing remodeling and looking to add insulation for improved comfort and energy effciency. Miost common construction is drywall, kraft faced R13, 2x4 walls, 3/4" Bildrite (asphalt fiberboard sheathing).
Can one add an inch or two of unfaced rigid foam to the exterior with out creating a vapor problem? How much foam is needed to be effective, without making the home too tight? Proposed is foam over current sheathing, then 1x3 strapping and cement board siding. Is this a good idea and would it be wise to put a 'raindrop' type house wrap over the asphalt sheathing - before the foam or after. New windows are generally part of the plan and obviously the flashing details are important. I am materials dealer, often asked for my advice or opinion by DIY homeowners who are trying to sort through all the information out there. Any advice would be appreciated.
Posted Thu, 04/17/2014 - 14:39
Edited Thu, 04/17/2014 - 15:19
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