1.5.zip May 2026

: The overlay typically provides a permeance level of 12–16 perms , allowing the panels to "breathe" and dry out.

Technical Analysis of 1.5-Inch ZIP System R-Sheathing in Modern Building Envelopes 1. Introduction 1.5.zip

The is a structural wood panel with integrated water-resistive barrier (WRB), air barrier, and thermal insulation. The 1.5-inch variant is a specific configuration designed to provide a continuous thermal bridge break while maintaining structural integrity in residential and commercial framing. 2. Composition and Specifications : The overlay typically provides a permeance level

: A factory-applied water-resistive and air barrier on the exterior face. Key Performance Metrics: R-Value : Provides a thermal resistance of R-6.6 . Key Performance Metrics: R-Value : Provides a thermal

: A layer of high-quality OSB that provides shear strength.

: In Climate Zone 5, the R-6.6 provided by the 1.5-inch panel is sufficient to keep the sheathing boundary above the dew point, preventing internal condensation when using fiber insulation in the stud cavity. 4. Application and Code Compliance

The primary benefit of the 1.5-inch ZIP-R system is the elimination of . In traditional framing, wood studs act as thermal bridges, conducting heat out of the building. The 1.5-inch ZIP-R provides continuous insulation that can cut wall heat loss by 20–30% compared to cavity-only insulation. Other advantages include: