Copying and pasting a wall or roof assembly that works in one part of our country into a project in another part of the country could be not just problematic, but potentially catastrophic. This presentation will use data and hygrothermal modeling to articulate what happens when tried and true assemblies from one part of the country get moved to a very different climate. More importantly, we’ll cover strategies to mitigate these issues. While many may be familiar with a Class I Vapor Retarder (“vapor barrier”) in the wrong part of an assembly, we’ll also cover the impacts of insulation type, the overreaction to perm ratings, light-colored roofing membranes, and reservoir claddings such as stucco and unit masonry.

Learning Objectives:

1. Learn climate-specific design strategies for durable construction.
2. Learn to avoid common mistakes that can lead to mold, rot, mildew, corrosion and decay.
3. Understand how hygrothermal modeling can be used in the design process to ensure durability.
4. Learn how material properties (permeability, heat capacity, density, conductivity, and porosity) impact wall assemblies.

John Posenecker, P.E.

John is a registered engineer in the State of Texas. His experience includes the design, construction, testing and forensic investigation of building envelope systems, with specialization in waterproofing and cladding systems associated with the building envelope.