ICC-ES AC342
Full Name
ICC-ES AC342 – Acceptance Criteria for Vapor Permeable Membrane Used with Concealed Attics and Roof Spaces
Scope
ICC-ES AC342 outlines the acceptance criteria for vapor permeable membranes (VPMs) used in concealed attic and roof spaces. The primary purpose of the VPM is to reduce air movement in the attic space, in order to control moisture vapor and improve the energy efficiency of the building.
The scope of AC342 includes:
- Materials: it specifies the requirements for the materials used in the VPM, ensuring they are suitable for use in attic and roof spaces and can withstand the expected environmental conditions.
- Performance: it outlines the testing methods and acceptance criteria for evaluating the performance of the VPM, including its vapor permeability, air permeance, tensile strength, tear resistance, and puncture resistance.
- Installation: it provides guidelines for the proper installation of the VPM, ensuring it is correctly positioned and secured to function effectively.
- Durability: it addresses the durability of the VPM, ensuring it can withstand long-term exposure to heat, moisture, and other factors present in attic and roof spaces.
The AC342 acceptance criteria are used by manufacturers to obtain an evaluation report from ICC Evaluation Service (ICC-ES), which demonstrates that their VPM products comply with the applicable building codes and standards.
Resources
Keywords
vapor permeable membrane; concealed attic; roof space; acceptance criteria; vapor permeability; air permeance; tensile strength; tear resistance; puncture resistance; installation; durability; heat resistance; moisture resistance; building code; standard; evaluation report