Today’s high-performance building market is driven by increasingly stringent energy codes and a growing demand for greater building efficiency, sustainability, and affordability. This means specifying and building masonry cavity walls and adhered masonry walls with materials working together as a functioning system is more critical than ever. When designing a highly functional masonry wall, the list of wall system performance criteria an architect must consider is daunting.
The wall must provide thermal efficiency, often with several types of insulation. In addition, it must offer air resistance while also managing moisture with properly designed and placed water-resistive barriers (WRBs). Further, the assembly must resist water leakage. However, when water does get in, it must be able to drain out of the cavity or from behind the adhered masonry veneer.
Due to their porous nature, masonry cavity walls are considered ‘rainscreen walls,’ and are expected to allow water into the cavity. Therefore, they must be designed to allow drainage and drying. Modern building science has shown high-quality adhered masonry walls such as stucco, stone, and thin brick also need to include drainage. The wall should resist vapour permeation, but when vapour penetrates, it must be able to dry, even when wetting and drying conflict with each other.
Structural connections are required to securely hold the entire system together, and at least three different modes of fire resistance should be considered, with multiple product warranties managed with these modes. Architects must provide the contractor with a complete list of material and system specifications to ensure the project can be bid accurately.
Contractors need to build with familiar, proven methods and readily available materials, and they should have complete installation knowledge of every component. When the project is complete, they must provide job closeout information such as credits earned under the Leadership in Energy and Environmental Design (LEED) program and warranty documents.
This insulation article along with two others appear in our newest ebook “Insulation Best Practices,” a free, downloadable resource. To get your copy in either pdf or digital edition, visit www.constructioncanada.net/ebook/owens-corning-insulation-best-practices-e-book.