Paper Conference

Proceedings of eSim 2002: 2nd Conference of IBPSA-Canada


Evaluation of critical factors affecting the thermal performance of metal curtain walls by simulations

H. Ge, P. Fazio

Abstract: An integrated method is employed in this paper to study the relative influence of certain design details on the thermal performance of metal curtain walls. Results from the programs FRAME/VISION, used to simulate the heat transfer across the wall systems, show that varying the configurations in the frame, can significantly improve the thermal performance of curtain walls. For example, the U-factor of the frame can be reduced as much as 60% by using a larger thermal break. The impact of the stainless steel screws is significant as well, and can reduce the Ufactor of the frame by up to 16% when the standard spacing of 152mm is applied. A simplified correlation model developed by Cornick & Sander is used to evaluate the effect of different improvement strategies for curtain wall systems on the energy consumption of a prototype office building subject to Montreal weather conditions. The results suggest that for curtain wall systems with poor frame performance, the simple use of high performance glazing unit would not yield significant improvement. Only when the frame performance is improved, the benefits of high performance glazing units are fully realized.