According to a recent study by Home Innovation Research Labs, more than 40 percent of all exterior walls in new single-family construction now use 2x6 assemblies—more than a 10 percent increase in a little over a decade. The Intertek-listed LPB/WPPS 60-01 2x6 exterior load-bearing wall assembly shows why these larger assemblies are getting more popular: fire code compliance plus higher R-values than most 2x4 assemblies.
This assembly uses LP FlameBlock Fire-Rated OSB Sheathing to meet rigorous fire codes for zero-lot-line construction where walls are close to the property line. A 2x6 stud creates 5½-inch wall depth to accommodate more insulation. The extra space offers numerous design advantages. Using mineral wool insulation in a 2x6 wall assembly increases the Sound Transmission Class (STC) rating compared to standard fiberglass insulation. This means that less outdoor noise penetrates the wall. Plus the additional mineral wool insulation in 2x6 assemblies can also achieve an R-value of 23 compared to the typical R-15 in 2x4 walls.
Architects who specify 2x6 exterior walls make many stakeholders happy. The wider top plate makes it easier for construction pros working in the attic. Homeowners obviously appreciate the significant increase in energy savings and reduction in sound transmission.
Twenty years ago, 2x6 framing was a novelty that had to be explained by gurus like Bob Vila. Now it’s becoming much more commonplace, especially in cold-weather regions. These larger assemblies achieve three important goals: meeting today’s tougher fire codes, providing greater energy efficiency, and lowering sound transmission from outdoors into the home’s interior.
LP and FlameBlock are registered trademarks of Louisiana-Pacific Corporation.
