Water intrusion around penetrations is the movement of water into the wall cavity at penetrations.
When you install a hose bib, dryer vent, or other fixture in the wall, you're creating a hole in the drainage plane. To prevent water intrusion, the drainage plane has to be continuous. Without proper flashing, water can enter the home through penetrations. Flashing maintains continuity, because it integrates with the drainage plane and directs water away from penetrations. Penetrations can create a pathway for water intrusion that may not be detected until the area around the penetration has sustained a large amount of water damage.
Using Preformed Flashing Panels
The best practice at penetrations is to use preformed flashing panels, such as Quickflash™ Panels. Preformed flashing panels are easier to integrate with the drainage plane, and they provide a better seal than tape, foam, or caulk. Tape, foam, and caulk are unreliable solutions for keeping water from entering around a penetration. They fill in or bridge gaps in the drainage plane, but they don't create a continuous surface. In contrast, flashing panels are integrated with the drainage plane material, since they're layered with the housewrap. Flashing panels are also easy to install, saving time and labor, while providing effective protection against water intrusion and the problems it causes.
Cause 1: Improper Flashing Using Only Tape, Foam, or Caulk
When you have penetrations in the walls, you create holes in the housewrap. Without proper flashing, water can enter the home through these holes. You can't rely on tape as the only way to seal penetrations, since tape loses its adhesion over time with moisture and temperature fluctuations. You can't rely on expanding foam and caulk, because they just fill a gap. None of these products can be properly integrated with the housewrap.
Solution
To create a continuous drainage plane and prevent water intrusion at penetrations, use a preformed flashing product that can conform to the exact size of the penetrating fixture. Once the preformed flashing piece is installed, integrate it shingle style with the housewrap.
ProTip! The flashing panel should be layered shingle style with the housewrap. The top of the flashing panel should be layered under the housewrap, and the bottom of the panel should be layered over the housewrap.
BuildIQ educates the homebuilding industry through training, tools, and information that enable builders to deliver high-quality, high-performance homes.