Steady-state thermal performance evaluation of steel-framed wall assembly with local foam insulation

During January and May, 2009, two configurations of steel-framed walls constructed with conventional 2 × 4 steel studs insulated with either R-19, approximately 14 cm (5.5 in.) thick, or R-13, approximately 9 cm (3.5 in.) thick, fiberglass insulation batts were tested in the Oak Ridge National Laboratory (ORNL) guarded hot box using the ASTM Standard C1363 test procedure. The first test wall used conventional 2 × 4 steel studs insulated with 2.5 cm (1 in.) thick foam profiles, called stud-snugglers. These stud-snugglers converted the 2 × 4 wall assembly into a 2 × 6 assembly, allowing application of R-19 fiberglass insulation. The second wall tested for comparison was a conventional 2 × 4 steel stud wall using R-13 insulation batts. Furthermore, numerical simulations were performed in order to evaluate the steady-state thermal performance of various wood-and steel-framed wall assemblies. The effects of adding the stud-snugglers to the wood and steel studs were also inve stigated numerically. Different combinations of insulation and framing factor were used in the simulations.