This paper presents the results of a study aimed at quantifying the change in the U-factor caused by glass plate curvature in sealed, insulated glazing (JG) units. The curvature may be caused by a number of factors, two of which will be studied in this paper-barometric pressure and gas space temperature variations. In the first part of this paper, the equations governing glass plate deflections and heat transfer through JG units are briefly reviewed Then, glass plate deflections and the resulting change in the U-factor of several JG units are examined for ASHRAE-type winter conditions.

Proceedings of a mini-conference held on 516 February 1997 at Abingdon, Oxfordshire, UK