Water-Resistive Barrier

Function & Code Requirements

Water resistive barriers are not required over concrete or masonry walls. Water resistive barriers are required over stud wall construction. As per 6.1.5.1 of the 2006 Building Code Requirements and Specification for Masonry Structures ( reported by the Masonry Standards Joint Committee (MSJC) “design and detail the backing system of exterior veneer to resist water penetration. Exterior sheathing shall be covered with a water-resistant membrane, unless the sheathing is water resistant and the joints are sealed.” Chapter 1404.2 of the 2006 International Building Code requires that a minimum of one layer of No.15 asphalt felt or other approved material shall be attached to the studs or sheathing so as to provide a continuous water resistive barrier behind the exterior wall veneer. Felt paper is commonly applied over exterior sheathing on wood or metal stud construction.

The International Building Code and International Residential Code typically requires that subgrade walls be dampproofed for conditions where hydrostatic pressure will not occur, and waterproofed where hydrostatic pressures may exist. Waterproofing systems include but are not limited to 2- or 3-ply hot-mopped felts, 50 mil rubberized asphalt, 40 mil polyurethane rubber, 20 mil vulcanized rubber, and 20 mil thermoplastic sheets. The barrier is part of a comprehensive system, which includes proper wall construction and the installation of drains, gutters, and proper grading.

• Air Barriers, Vapor Retarders and Weather-resistive Barriers: Are They All the Same?
• Water Repellents for Concrete Masonry Walls
• Preventing Water Penetration in Below-Grade Concrete Masonry Walls

Companies Offering Air Barriers

Company	City	State
PROSOCO, Inc.	Lawrence	KS
Hohmann and Barnard, Inc.	Hauppauge	NY
Advanced Building Products, Inc.	Sanford	ME
Mortar Net Solutions	Portage	IN
Crown Masonry & Construction Materials, LLC	Kansas City	KS
Ernest Maier, Inc.	Bladensburg	MD
MASONPRO, Inc.	Northville	MI
Masonry Accessories, Inc.	Orlando	FL
Thompson Building Materials, Inc.	San Diego	CA
Tucker-Kirby Co.	Charlotte	NC
Waldo Bros. Company	Boston	MA