Water infiltration caused by faulty windows or installation procedure is a common source of building failure leading to mold infestation and water damage. Because water infiltrating through window assemblies will often leak directly into the wall cavity, a problem can go undetected for a long time and once it is discovered the damage is often extensive.
Such problems can be avoided if the proper testing protocol is carried out at the time of installation. Some windows are designed with drainage channels and weep holes that allow water to drain to the outside of the building and not into the wall. One way to test the effectiveness of a windows drainage capacity is to temporarily block the weep holes with putty and then fill the drainage channel with water. If the window is properly manufactured and installed, the water should not drain out of the drainage channel when the weep holes are plugged. This test should be performed on each window for a minimum of 15 minutes. Be sure to remove the putty from the weep holes when the test is complete.
