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Title: Surface reflectance degradation by microbial communities

Building envelope, such as a roof, is the interface between a building structure and the environment. Understanding of the physics of microbial interactions with the building envelope is limited. In addition to the natural weathering, microorganisms and airborne particulate matter that attach to a cool roof tend to reduce the roof reflectance over time, compromising the energy efficiency advantages of the reflective coating designs. We applied microbial ecology analysis to identify the natural communities present on the exposed coatings and investigated the reduction kinetics of the surface reflectance upon the introduction of a defined mixture of both photoautotrophic and heterotrophic microorganisms representing the natural communities. The result are (1) reflectance degradation by microbial communities follows a first-order kinetic relationship and (2) more than 50% of degradation from the initial reflectance value can be caused by microbial species alone in much less time than 3 years required by the current standard ENERGY STAR® test methods.
 [1] ;  [1] ;  [1] ;  [2] ;  [3] ;  [3] ;  [4]
  1. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
  2. L&N STEM Academy, Knoxville, TN (United States)
  3. Univ. of Tennessee, Knoxville, TN (United States)
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Building Physics
Additional Journal Information:
Journal Volume: 47; Journal Issue: 2; Journal ID: ISSN 1744-2591
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Building Technologies Research and Integration Center (BTRIC)
Sponsoring Org:
Work for Others (WFO)
Country of Publication:
United States
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; building envelope; microbial degradation; coating; biokinetics
OSTI Identifier: