Accession Number : ADA298686

Title :   Roof Blisters: Cause and Cure.

Descriptive Note : Special rept.,

Corporate Author : COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH

Personal Author(s) : Korhonen, Charles ; Charest, Brian

PDF Url : ADA298686

Report Date : JUL 1995

Pagination or Media Count : 13

Abstract : Blisters are a major problem of built-up roof membranes. They are caused by voids built into the roof during construction. They develop into the characteristic dome-shaped humps by a breathing action driven by thermal cycling. A small pressure relief vent was patented by CRREL as a cost-effective way to repair blisters. Though these vents cannot prevent blisters from forming, they can lengthen a roof's service life by repairing the blisters before they break. Two demonstration projects were conducted to transfer the blister vent technology to the military community. Most participants in the demonstration projects found the vent easy to use and that it performed as designed. The main objection to the vent was its price. (MM)

Descriptors :   *VENTS, *ROOFS, *BITUMENS, COST EFFECTIVENESS, AGING(MATERIALS), LIFE EXPECTANCY(SERVICE LIFE), EMBRITTLEMENT, VOIDS, GASES, DEFECTS(MATERIALS), REPAIR, THERMAL EXPANSION, BUBBLES, MEMBRANES, RESPIRATION, THERMAL STRESSES, WEATHERING, CYCLIC LOADS, BITUMINOUS COATINGS.

Subject Categories : Air Condition, Heating, Lighting & Ventilating
      Structural Engineering and Building Technology

Distribution Statement : APPROVED FOR PUBLIC RELEASE