As a Building Official In Connecticut I am constantly confronted by builders choosing to use kraft faced fiberglass insulation. As we are now enforcing the IECC 2009 installation methods and practices that were wrongly accepted for thirty years need to change. Tabs stapled to the inside of framing members is unacceptable and has been wrong for 30 plus years but acce[ted as common practice and approved. Technically this also does not pass the "continuous vapor retarder required by the IBC and IRC. In reality the tabs are not vapor proof because they do not have the asphalt glue that binds the fiberglass to the paper and acts as the vapor retarder in conjunction with the paper facing. Most builders choose the fiberglass because of product cost and ease of installation which reduces labor costs. Is using unfaced fiberglass insulation properly installed, with a continuous poly vapor barrier a better way to handle the situation. It covers the code and properly installed and sealed should prevent moisture vapor from entering the wall cavity through the sheetrock. What are the negative aspects if any that you see. Many insulation contractors do not believe in poly vapor barriers, but these are the same people who continue with sloppy installation and stapling the facing to the inside of the framing members. If we are going to still accept fiberglass insulation is unfaced with poly a better choice.
Ed Palma, Town of North Haven, Connecticut Building Department, LEED, NAHB CGP,
Connecticut Contractor HIC #561267
Posted Jul 19, 2012 10:06 AM ET
Other Questions in GBA Pro help
Can unvented roof assemblies be insulated with fiberglass if I use rigid foam on the exterior of the sheathing?