AT-90-07-2 -- An Evaluation of the Representativeness of Glazing Product U-Values in the ASHRAE 1989 Fundamentals Volume

First, glazing products and features that are not included in the ASHRAE product listing are identified. Second, the glazing product U-values in the ASHRAE and Seattle product listings are compared on a general basis. Third, U-values are calculated using the ASHRAE product listing procedure and are compared with tested values in the Seattle product listing for individual products. Also, an assessment is made of the representativeness of the generic glazing products in the ASHRAE product listing. Finally, based on the previous evaluation, recommendations are offered for future research to improve the accuracy and ease of use of the calculation procedure.

KEYWORDS: thermal resistance, calculating, comparing, glazing, heat flow, USA, windows, double glazing, triple glazing.