Conductive Heat Transfer through Insulated Building Enclosure Components: A Cross-Section Analysis of Constructions Typical to Low-Rise Residential and Commercial Buildings in North America

Abstract

The main purpose of thermal insulation in buildings is to reduce conductive heat loss and maintain appropriate interior surface temperatures. How ever, ensuring the desired performance requires not only good workmanship during construction but also careful prediction of the hygro-thermal behavior of building components with complex geometry and material composition (thermal bridges). This paper includes the results of a study of insulated building components typical to the construction practice in North America, concentrating on low-rise residential and commercial buildings. It deals specifically with the significance of the accurate simulation of conductive heat transfer for both energy (heat load calculations) and building integrity issues (surface condensation).

Keywords

residential buildings North American constructions insulated building components thermal bridges hygro-thermal analysis finite differences numeric methods surface condensation thermal coupling coefficient temperature weighting factor.

Get full access to this article

View all access options for this article.

References

Cen. 1991. DOC CEN TC89/WG1/N156. Thermal Bridges- Calculation of Surface Temperatures and Heat Flows ; working draft for a European Standard (EN).

Heindl, W. , K. Krec , E. Panzhauser and A. Sigmund. 1987. Warmebrucken Wien, New York: Springer.

Huang, Y.J. et al. 1987. Methodology and Assumptions for Evaluating Heating and Cooling Energy Requirements in New Single Family Residential Buildings Berkeley, CA: Lawrence Berkeley Laboratories.

Iso 6946/1. 1986. Thermal Insulation- Calculation Methods-Part 1 Steady State Thermal Properties of Building Components and Building Elements Ref. No. ISO 6946/1-1986 (E).

Mahdavi, A. 1993 (to be published). "Computational Framework for Numeric Assessment of Steady State Conductive Heat Transfer through Thermal Bridges," ASHRAE Meeting, Chicago

. Mahdavi, A. and P. Mathew 1992. "Hygro-Thermal Behavior of Building Components with Regard to Their Impact on Energy Consumption and Indoor Climate," CIB '92, World Building Congress, Montreal , Canada.

Nahb. 1981. Sustained Builder Survey Responses Result in Data Bank of Over One Million Houses Rockville, MD: NAHB Research Foundation, Inc.

Onorm. 1991. ONORM B 8110 Tell 2, May 1991 (Entwurf, Vornorm), Warmeschutz im Hochbau, Wasserdampfkondensation (Thermal Insulation in Building Construction; Water Vapor Condensation). Vienna: Osterreichisches Normungsmstitut .

Panzhauser, E. and A. Mahdavi. 1989. "Warmedammung und Feuchtigkeitsbeanspruchung," Bauforum, 135:55-58.

10.

Panzhauser, E. , A. Fail , A. Mahdavi and W. Hemdl. 1990. "Characteristic Values for Thermal Behavior of Building Components Compared with Respect to Their Practical Usability," International CIB W67 Symposium on Energy, Moisture and Climate in Buildings, Rotterdam.

11.