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Author
Burch, D. M.
Title
Infrared Audits of Roof Heat Loss.
Coporate
National Bureau of Standards, Washington, DC
Journal
ASHRAE Transactions, Vol. 86, No. Part 2, 209-226, 1980
Report
No. 2600,
Keywords
roofs | heat loss | infrared thermography | thermal resistance | mathematical models | radiance temperature | roof emittance | local outdoor temperature | wind velocity
Abstract
The paper investigates whether a comparative roof survey using aerial infrared thermography can be used to rank the roofs of residential and commercial buildings according to their thermal resistance. Mathematical models are presented for predicting the apparent radiance temperature of these roof systems. These models are used to investigate the differences in apparent radiance temperature between roofs having various thermal resistances. These predicted differences are then compared with predicted differences in apparent radiance temperature caused by typical variations in roof emittance, local outdoor temperature, and local wind speed throughout the macroclimate. The required dew-point spread for preventing dew or frost formation on a roof is examined.