DuPont™ Tyvek® weather barriers are trusted by building professionals to provide performance that ZIP System® wall sheathing and tape can’t.
The unique material and building science behind Tyvek® weatherization products provides the optimal balance of protection against air and bulk water infiltration and vapor permeability. And Tyvek® weather barriers deliver superior overall performance, compared to ZIP System® Wall Sheathing, in five key areas:
In testing conducted by the Home Innovation Research Lab at the request of DuPont, five installation crews participated in a series of experiments designed to test the ZIP System® manufacturer’s claims of easier, faster installation. Each crew was timed while installing the ZIP System® and the complete DuPont Tyvek® Weatherization System and sheathing, following manufacturers’ installation instructions, on a framed two-story structure that included three standard double-hung and three round top windows. Test results showed no significant installation time advantage for the ZIP Systems® wall sheathing and tape over the DuPont™ Weatherization System.
Several reasons were cited, including the need for every seam of ZIP System® Wall Sheathing to be taped and rolled; the need to maintain precise 1/8” spacing between every seam; and the need fordry conditions and surfaces before taping.
By comparison, Tyvek® products can be installed under most weather conditions, and underlying sheathing can be installed more quickly, because every corner and seam does not need to be taped and rolled.
DuPont™ Tyvek® weather barriers are constructed of a strong, nonwoven material, so they are resistant to tearing and puncturing and stand up to the demands of job-site conditions. Any small punctures that may occur can be easily repaired, using Tyvek® tape. And even larger tears or holes can be repaired, using a combination of the same Tyvek® product and Tyvek® tape.
ZIP System® Wall Sheathing is constructed of an oriented strand board (OSB) structural panel with a resin-impregnated Kraft paper overlay. So, it must be handled with care to avoid taking on moisture before installation. Failure to do so can result in damage to the panels, potentially compromising the integrity of the wall system, if not carefully repaired.
The bulk water hold-out capability of ZIP System® Wall Sheathing depends on taping of all joints and corners. Improper taping can allow water to enter the system, reducing the performance of the ZIP System® Wall Sheathing and the entire wall system.
Conversely, Tyvek® building wraps are comprised of a precisely bonded barrier, for high bulk water hold-out and breathability. So bulk moisture absorption is never an issue.
For a weather barrier to be considered vapor permeable, it must have a vapor permeance of at least 5 perms (IRC) or 10 perms (IBC) as tested per ASTM E96 B (desiccant method).
Tyvek® weather barriers have permeability ratings that range from 28 to 56 perms, which ensure greater drying capability of the wall system.
ZIP System® Wall Sheathing has been shown in laboratory testing conditions to have a vapor permeance of less than 1 perm, under both wet and dry cup measurement conditions– which means it may actually contribute to trapping moisture.
When installed as an air barrier, Tyvek® materials meet Sections R402.4 and C402.4 of the 2012 International Energy Conservation Code, as well as the 2009 IECC. These sections require airsealing methods that allow for expansion and contraction of building materials.
Put simply, Tyvek® weather barriers are not affected by the movement of sheathing materials, which in turn can help maintain a better continuous air and water barrier.
ZIP Systems® Wall Sheathing is wood-based sheathing with a water-resistive overlay, a type of material not designed to provide the optimal balance of air and water protection and breathability.
ZIP System® is a registered trademark of Huber Engineered Woods LLC.