A quantitative aerial infrared thermographic method for the determination of residential roof top heat loss is studied utilizing data gathered on over 1000 homes in the city of Plattsburgh, New York. The aerial infrared thermographic technique used as the basis of this study accounts for atmospheric and emissivity effects on the thermogram data as well as convective and radiational losses from the roof surface. The strength of the method is tested on the basis of a multivariate first order linear regression analysis using the aerial heat flow measurements as the dependent variable and parameters derived from ground survey data as the independent variables. This analyses shows that using relatively simple models, a large portion of the variance in the dependent variable can be explained using the ground survey data. Results indicated that a value of R2 = 0.83 for the regression model can be obtained at a standard error in the dependent variable of less than 7 w/m2 over a range of heat flow values from 22 to 82 w/m2. The models constructed use insulation level, inside temperature, attic ventilation, and roof condition as parameters in the predictive equation. The modelling process was structured such that parameter inclusion was based on minimizing the standard error in the predictive equation. The quantitative thermography method was found to make significant errors in heat loss classification (based on a five class heat loss rating system) only one percent of the time based on an analysis of 90 residential structures. To contrast the results of the state of the art method with more commonly used technology, a classical (qualitative) interpretation method indicate that the classical approach has a tendency to deliver misleading results. The classical method was found to be in agreement with the more sophisticated method only 36% of the time. Indeed, the image interpretation approach traditionally employed placed 21% of the nearly 1000 homes studied two or more classes away from the class defined by the quantitative techniques, indicating the superiority of the advanced technology.
Library of Congress Subject Headings
Remote sensing; Thermography; Roofs--Thermal properties--Evaluation
Imaging Science (MS)
Department, Program, or Center
School of Photographic Arts and Sciences (CIAS)
Biegel, Joseph, "Evaluation of a quantitative aerial thermography method for the determination of roof top heat loss" (1986). Thesis. Rochester Institute of Technology. Accessed from
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