While nearly all wall construction should have flashings, they are often missing, or more often, are improperly installed. Wall flashings are often the most important component in a wall system.
One important component in controlling water in wall systems is the proper design and installation of flashings. Due to its importance, the flashing should have an anticipated life at least matching the expected life of the building.
Rain, snow, ice, water vapor and condensation cannot be prevented, and all are sources that infiltrate building envelopes. Water is the universal solvent and it is responsible for many problems. Water causes deterioration in building materials through several mechanisms, including dimensional changes in construction materials; cyclic wetting and drying; freezing and thawing action; corrosion and many others. Since water cannot be eliminated, its penetration must be controlled. One important component in controlling water in wall systems is the proper design and installation of flashings.
Observing new building construction is always exciting and at the same time unnerving. Exciting because it indicates that our economy is growing. Unnerving because of the design techniques, construction practices and technical skill being incorporated into many projects. It seems that more and more buildings are being constructed without attention to the details that make a real difference when it comes to keeping water out.
The bottom line is that flashing is critical to the water resistance and sustainability of nearly all wall systems.