DuPont changed the homebuilding industry and opened up a whole new market with the introduction of Tyvek housewrap in the last century. Invented in 1967, Tyvek started to be common on houses in the early 1980s, superseding asphalt felt paper as the siding underlayment of choice. Now, you see it — or other products like it —on almost every new house.

But housewrap isn't the latest thing in weather-resistive barriers any more. Along with more breathable high-tech membranes, high-performance builders are increasingly switching to fluid-applied membranes as a water-tight but vapor-open protective layer for wood sheathing before siding is applied.

Austin, Texas, builder Matt Risinger touched on the technology in the May 2015 JLC (see: "Weather Barrier Update: Good, Better, and Best," by Matt Risinger.) "Fluid-applied WRBs are elastomeric products that can be sprayed, rolled, and even brushed on a wall," Risinger explains. "Depending on the product, some joint and seam filling or priming may be needed first. The cured products form an elastic, airtight, vapor-permeable, and waterproof covering that will stretch and contract a bit as a building moves."

One example of the category is Tyvek Fluid Applied WB. Risinger took an early look at the product in an on-site interview in 2012 with his local DuPont rep, Cory Ball (see "Fluid Applied Tyvek — First Look"). Below is part two of Risinger's early look, where Risinger and Ball demonstrate how to use the DuPont system to waterproof and air-seal a recessed window set into a deep wall (see: "Fluid Applied Tyvek - Recessed Window Install Best Practice How To").

Still curious? DuPont provides its own series of demonstration videos for its fluid-applied approach, a seven-video set titled "DuPont™ Tyvek® Fluid Applied WB Install." Below is the first video in the series, "Preparing a CMU Wall for Application of Fluid Applied WB | DuPont™ Tyvek®."