Improving ASTC Performance Of As-Built Wood-Frame Double-Shear Panel Wall Assemblies

摘要

As noted in the initial comparative study on this specific subject, acoustical engineers often encounter designs specifying multiple cavity partitions, with the expectation that they will provide equal or greater sound transmission loss performance than a single cavity partition of similar overall mass and dimension. That study confirms that this is not generally true, in particular for double-stud wood-frame and dry wall demising partitions with structural shear panels on the inner faces of the studs. Using field results, it concludes that such configurations should be avoided in design where the goal is to achieve Sound Transmission Class (STC) ratings of 50 or higher. It also notes that these conditions nevertheless appear in the field with a high risk of not conforming to building code requirements. Options to improve the performance of these walls were previously suggested, but had not been field verified. This article compares field performance of several partitions, and presents the acoustical effects of a commonly encountered shear configuration and mitigation scheme.