No matter how tightly a building is constructed, no matter how well it’s insulated, no matter what type of exterior cladding is chosen and how expertly it’s installed, moisture will always find a way into the building enclosure. Moisture infiltration can undermine structural integrity, cause exterior surfaces to deteriorate, and shorten life of paints and stains. It can also foster mold and rot that not only cause structural damage but also pose serious health hazards. Ridding the wall assembly of liquid water and water vapor as quickly as possible (before it can damage structural components) is what moisture management is all about.

There are many moisture management products currently on the market and choices are expanding to include traditional felt paper, rainscreen systems, sealants, and self-adhered flashing membranes. That’s where housewraps enter the scene. Installed behind siding, they prevent wind-driven rain and water from reaching the sheathing and framing, and reduce air infiltration, helping to decrease heating and cooling costs. In addition to resisting initial moisture infiltration, housewraps go a step farther by helping to remove trapped moisture vapor from the building enclosure.