foil backed foamboard /attic barrier
I want to put 2 layers of foil backed foamboard 1/2″ thick on upstairs walls that are exposed to attic heat.
Thinking that I would face foil to inside on first layer then over lap seems with foil backing facing attic on second layer.Should make for an R-6 factor.
Infrared thermometer shows the walls reading almost 90 degrees with the upstairs a/c running all the time.
Are there any studies or testing results out there on this and what are your real world results?
ANDYSZ2
WHY DO I HAVE TO EXPLAIN TO FRIENDS AND FAMILY THAT BEING A SOLE PROPRIETOR IS A REAL JOB?
REMODELER/PUNCHOUT SPECIALIST
Replies
Greetings Andy,
This post, in response to your question, will bump the thread through the 'recent discussion' listing again which will increase it's viewing.
Perhaps it will catch someone's attention that can help you with advice.
Cheers
This past winter I added 2" foil faced Thermax to the exterior of knee walls on the 2nd floor of my house. The material was expensive but I wanted the piece of mind because it is rated to be exposed for fire rating. It has foil facing on both sides. The area ware I was working was tight and wanted to only go in there once and get the best bang for my efforts. Made a big difference.
Yeah, lots of recent discussions per rez.
May be no point in going through trouble of 2 layers ... just use polyiso ... it has foil both sides. (maybe I missed something in your description?) Remember, for the foil to work the best, it has to face an air space. If you put e.g. sheetrock right on top, it significantly reduces its ability to perform.