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NAHBRC - National Association of Home Builders Research Center





In collaboration with the National Association of Home Builders Research Center (NAHBRC) and the American Iron and Steel Institute (AISI), work was initiated to determine the steady-state thermal performance of thermally efficient steel frame wall designs and to evaluate various means of improving the energy efficiency of these systems. As part of this arrangement, the Buildings Technology Center (BTC) of the Oak Ridge National Laboratory (ORNL) performed a series of tests on four such wall systems.

The test plan called for a total of four walls to be tested in ten different configurations. The base test configurations consisted of a nominal 2 x 4 standard steel-framed wall and a nominal 2 x 6 slit stud wall, with the common characteristics of 0.5-in. thick gypsum drywall on the warm side, 0.5-in. thick oriented strand board (OSB) on the cold side, and full-width fiberglass batt insulation in the cavities. Variations of the base walls tested included modified track/stud combinations, application of a thin profile thermal break material between the framing and OSB exterior, and application of thin foam sheathing on the exterior wall surface. The following shows a picture of one of the typical slit studs used in tests 3 through 10.


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