MOISTURE IN THE ROOFS OF COLD STORAGE BUILDINGS

The low-slope roofs of 10 cold storage buildings in the Dallas area were examined visually and thermographically from above and below. Cores were taken to verify infrared findings, and 12- x 12-in. (30 x 30-cm) specimens of many of the insulations were removed for laboratory studies of their thermal properties. Insulations included fibrous glass, fiberboard, perlite, wood fiber, expanded and extruded polystyrene, isocyanurate, and phenolic. Areas of wet insulation were found in 8 of the 10 roofs. Some wetness was due to leaks caused by flaws in the roofing membranes and their flashings, but some was associated with infiltration of warm, moist outside air at roof-wall intersections without effective air seals. Of all the insulations examined, permeable fibrous glass was the most susceptible to wetting by air infiltration. Sustained one-way vapor drive, the sealing-in of moisture at the base of insulation in roofs of cold storage buildings by freezing, and the limited opportunities for drying wet insulation in such roofs provide incentives to use insulation that is very resistant to wetting. Its very low rate of moisture gain by vapor diffusion and its resistance to wetting in the presence of freeze-thaw cycles make extruded polystyrene insulation particularly appealing for use in the roofs of cold storage buildings.

• Corporate Authors:

  U.S. Army Cold Regions Research and Engineering Laboratory

  72 Lyme Road
  Hanover, NH  United States  03755-1290

  Owens Corning

  One Owens Corning Parkway
  Toledo, OH  United States  43659
• Authors:
  • Tobiasson, W
  • Greatorex, A
• Publication Date: 1998-11

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: 42 p.

Subject/Index Terms

• TRT Terms: Building; Electric insulating materials; Extrudates; Freezing; Infrared analysis; Insulating materials; Leakage; Moisture content; Polystyrene; Refrigeration (Structures); Refrigeration (Vehicles); Refrigerators; Roofs; Storage facilities; Styrenes; Thaw; Thermal properties
• Uncontrolled Terms: Freeze thaw cycles; Wet conditions
• Old TRIS Terms: Cold storage; Freezers
• Subject Areas: Construction; Geotechnology; Highways; Materials; Terminals and Facilities; I35: Miscellaneous Materials;

Filing Info

• Accession Number: 00758933
• Record Type: Publication
• Report/Paper Numbers: Special Report 98-13
• Files: TRIS
• Created Date: Jan 14 1999 12:00AM