Smell from polyiso roof insulation

Log Out | Topics | Search Moderators | Register | Edit Profile

Author Message Louis Medcalf, FCSI, CCS Senior Member Username: louis_medcalf Post Number: 32 Registered: 11-2010 Posted on Friday, September 26, 2014 - 09:18 am:    One of our clients started experiencing an obnoxious odor that appears to be coming from polyiso insulation under an adjacent lower metal roof during hot weather. The building is 11 years old, but the problem did not start until about 5 years ago. The insulation is installed over polyethylene sheets on metal deck, and there is layer of 30 lb asphalt felt on top of the insulation. The metal roofing is industrial type with trapezoidal seams that may provide a channel for off-gassing to move to the wall of the building. A sample taken from the roofing is very friable. IAQ testing indicates the smell is not a health hazard, merely unpleasant. Has anyone had experience with a similar situation? Is it normal for 11-year old polyiso to turn into dust when the exposed edges are rubbed by hand? Because the roof system has top and bottom vapor barriers, would moisture build-up somehow exacerbate outgassing and the 'plasticy' smell? Direct e-mail or calls also appreciated. Scott Piper Senior Member Username: spiper Post Number: 7 Registered: 08-2014 Posted on Monday, September 29, 2014 - 12:24 pm:    I have seen polyiso board that has been wet and then dried out and it did get powdery so the top and bottom vapor barriers could be an issue. However, while there may have been an odor but I did not detect one.