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Discussion Starter #1
Hello,
I have some questions for anyone familiar with the foil-faced "bubble wrap" type insulation. (I'm not sure of the correct name for it but hopefully you know what I mean.) I have a cabin I'm refurbishing which has very little insulation. The walls have some fiberglass insulation with vapor-barrier paper between the studs, but there seem to be quite a few gaps. The outside currently has vinyl siding, but it is broken/cracked in several places. I'm planning to pull it off and put 1" rigid foam board insulation (w/o vapor barrier) up and cover it with board and batten. A friend has been raving about the bubble wrap insulation, and suggested I place it over the rigid foam before putting up the board and batten. He seems to feel this would greatly improve the effectiveness. I have 2 questions: Do you feel this is worth doing? And, given that there is the insulation between the walls with a vapor barrier, would putting this on the outside trap moisture between the two? There seem to be enough gaps in the insulation between the studs that I don't think this would be a problem, but I don't want to find out the hard way. Any advice from someone experienced with this stuff - and insulation in general - would be appreciated. Thanks.
 

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Why board and batten?
Your trying to tighten up the building envelope, then add a form of siding that will have gaps across the whole wall on the outside.
It also will be far more manitaince then other options.

I'd skip the bubble wrap under the siding. And in fact the foam also.
Your going to end up with several layers of vaper barrier.
Just add some Tyvek house wrap.
 

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Discussion Starter #3
Two reasons for the board and batten: part of the cabin is already done in it, and I like the rustic look. The cabin is deep in the woods, 1 1/2 miles off the paved road. It just seems out of place to put vinyl siding on it.

I freely admit I don't know much about the subject, but I thought Tyvek was just a vapor barrier. Would it do anything to improve the R-value?
 

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Welcome to the forums!

Where are you located?

If
in a heating climate, the paper-faced batt insulation is variable perms, exactly what you want on the inside (though it can be omitted when using foam board, if thick enough); http://www.buildingscience.com/documents/reports/rr-0004-air-barriers-vs-vapor-barriers

Most the housewraps are vapor permeable to different degrees. They let moisture through, and if sealed= stop air flow. The radiant foil bubble wrap is not effective without a 3/4" air space next to it. I'd pass on it and use the foamboard to stop the thermal bridging and keep the cavity warm to deter condensation; http://www.greenbuildingadvisor.com/blogs/dept/musings/are-dew-point-calculations-really-necessary

Don't believe everything you hear: http://www.energyvanguard.com/blog-building-science-HERS-BPI/bid/29497/The-Foil-Faced-Bubble-Wrap-Sham-Understanding-Radiant-Barriers

And: http://www.healthyheating.com/Page 55/Page_55_o_bldg_sys.htm#MNEC
You will reap more with better insulation, air seal the walls/ceiling/floor, and ADA the drywall: http://www.buildingscience.com/documents/information-sheets/air-barriers-airtight-drywall-approach/

Have you looked at "rain-screens"? http://www.nchh.org/Portals/0/Contents/Article0440.pdf

Gary
 

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Discussion Starter #6
The cabin is located near Coudersport, PA. I'm getting ready for work now and don't have time to check out all the links you sent, but I'll definitely give them a close look when I get home. Thanks for your reply!

Bob
 
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