FIELD-EVALUATION OF WATER PENETRATION INTO SPRAYED-ON POLYURETHANE FOAM INSULATION

A field study of seven potato storage buildings and six hog barns insu lated with sprayed-on polyurethane foam insulation (PUFI) was carried out and compared with laboratory tests that showed that water will mig rate into PUFI when subjected to a high water vapour pressure. Samples from one of the potato storage buildings were examined for moisture c ontent using gamma spectrometry, visual inspection, and by drying and weighing. Samples from all other buildings were only tested by drying and weighing and by visual inspection. None of the hog barns had insul ation that had become wet, although all structures were older than ten years. Two of the potato storage buildings had PUFI that was very wet to the point that the insulation value had reduced by about 50%. Two others had insulation with an average water content over one percent b y volume, a significant amount of water. The remaining three potato st orage buildings did not appear to be affected by the high moisture con ditions inside.