Page 18 - GB Building Science Ebook 2019
P. 18
02 NEW INSULATION AND THERMAL BRIDGING TOOLS
HOW RIGID FOAM REDUCES CAVITY MOISTURE
Test show that insulated sheathing results in higher temperatures in the stud cavity,
which increases moisture evaporation and drying to the interior.
Insulated Sheathing Housewrap Alone Over OSB
PHOTO: ENERGY STAR
PHOTO: ORNL
WANTED: AFFORDABLE VACUUM PANELS
ACUUM INSULATED PANELS have been rolled out in Laboratory (ORNL) is working on a new way to reduce the cost of
recent years, as a way to pack more R-value into thinner this technology. Their version of the vacuum process results in
panels. So far, these products have not achieved the price something called modified atmosphere insulation. Performance is a
V parity with existing building products to win wide appeal. respectable R-12 per inch, far less than the R-30 per inch achieved
The cost of one commercial brand, Optim-R, for example, hovers by true vacuum technology, but still twice that of most comparable
around $10/sq. ft. The Department of Energy’s Oak Ridge National foam products.
18 BUILDING SCIENCE SPECIAL REPORT: SIX WAYS CONSTRUCTION IS CHANGING
