Thermal and shear wall performance of building assemblies with insulated frames.

A technique for improving the thermal performance of lightweight steel- and wood-framed building assemblies is introduced in this paper. In this approach, rigid extruded insulation material is applied only to the framing members themselves (studs, plates, doubles, headers, etc.), effectively creating a composite member composed of insulation and structural framing. The depth of the envelope cavity is thereby extended by an amount that is equal to the thickness of the rigid insulation employed. The deepened cavity can then be filled completely with the designer's choice of insulation materials. The ASTM C 976 Thermal Performance of Building Assemblies test was used to verify the thermal benefits of this approach. This empirical result is then compared with two-dimensional computer heat transfer simulations. A series-parallel path discussion of insulated wood-framed assemblies is also presented in this paper. Finally, static shear wall performance of assemblies framed with insulated steel is evaluated