Wall construction - Improving the envelope

New guides educate builders on “next-gen” wall construction

High-performance homes are now required by model codes (2012/2015 IECC) and promoted by voluntary standards, such as the National Green Building Standard and Energy Star, yet less than 20% of all new homes have energy-efficient walls with an R-value of 19+. To help address this market gap, Home Innovation has recently authored a two- part builder guide that provides best practices for building walls that are energy efficient, durable, and cost-optimized—and that can be implemented easily in the field.

Parts 1 and 2 of the “Construction Guide to Next Generation High Performance Walls in Cli- mate Zones 3-5” were developed with input from a range of experts across the industry to help achieve greater standardization for this type of high-performance construction. They present the pros and cons of the various options available and are designed to pro- vide practical guidance to help builders make informed design and material selection choices.

With this two-part guide you can:

Learn best practices and specific solutions for integrating exterior rigid foam insulation, including details for window installation, siding attachment, and weather- resistive barrier (WRB) integration.

Examine advanced framing packages that combine tried- and-true techniques with new approaches for increasing the wall system’s R-value while controlling costs.

Know where energy-efficient options and materials can conflict in installation practices and lead to product failures or inspection red flags for non-compliance.

Understand the selection of vapor retarders for energy- efficient walls and other moisture performance considerations.

Part 1 of the guide addresses walls constructed with 2x6 wood frame studs, wood structural panel (WSP) exterior sheathing, and a cladding system installed over WSP sheathing in low-rise residential buildings up to three stories high. Part 2 addresses walls constructed with 2x4 wood frame studs, WSP sheathing as wall bracing and add- ed backing for foam sheathing, a layer of rigid foam sheathing insulation up to 1 1⁄2 inches thick over the WSP, and a cladding system installed over the foam sheathing in low- rise residential buildings up to three stories high. To download both parts of the guide, visit www. homeinnovation.com/wallguides.