One reason for the complexity of the International Building Code is the complexity of the building environment. From Key West, Florida, to Bangor, Maine, to Seattle, Washington, to San Diego, California, to Las Vegas, Nevada, and everywhere in between, there is a wide diversity of seismic activity, wind speed, and climate that buildings must bear up under. The challenges are great for building envelopes, which must keep the water, air, vapor, and heat of the surroundings from affecting the interior space. But despite all the possible combinations of climate to be found in North America, there is one basic design that works from sea to shining sea.
Sometimes called the perfect wall, this design sandwiches all four control layers (water resistive barrier, air barrier, vapor retarder, and thermal insulation) between the wall’s cladding and framing. No insulation is placed in the wall cavity between framing members. The cladding protects the control layers from UV, wind, and precipitation, while the control layers protect the structure of the building from temperature fluctuations and moisture. The only variable based on location is the amount of insulation needed. To learn more about why this design is so effective, take a look at these resources, and more available throughout the site.
Also worth watching is the following video, part of a series where Joe Lstiburek gives a broad outline of the ‘perfect wall’ concept:
For additional information, review the following articles, as well as the previous videos in this series:
Perfect Wall Articles
- Creating the ‘Perfect Wall’: Simplifying Water Vapor Retarder Requirements to Control Moisture
- Perfect Walls are Perfect, and Hybrid Walls Perfectly Good
- Wood Framed Wall Insulation Calculator Explained
- New Wall Design Calculator for Commercial Energy Code Compliance
- Energy Code Math Lesson: Why an R-25 Wall is Not Equal to a R-20+5ci
- Continuous Insulation Solves Energy Code Math Problem
- Fear Building Envelopes No More with This Website & Videos
- Video: Thermodynamics Simplified Heat Flows from Warm to Cold
- Video: Moisture Flow Drives Water Induced Problems
- Video: How the 'Perfect Wall' Solves Environmental Diversity
- Video: How Important Is Your WRB?
- Video: A Reliably Perfect Wall Anywhere
- Video: The Best Wall We Know How to Make
- Video: How to Insulate with Steel Studs
- Video: Thermal Bridging and Steel Studs
- Video: Better Residential Energy Performance with Continuous Insulation
- Video: How to (Not) Ruin a Perfectly Good Wall
- Video: Tar Paper and Continuous Insulation? No Problem!
- Video: Do CI and WRBs Go Together?
- Video: Assess Your 'Perfect Wall' Using Control Layers