When a homeowner notices water coming into their home at the window, the instinctual response is to instantly blame the window or it’s installation, when in many cases, the window is merely the victim of the evidence.
If you have a leak ANYWHERE on the wall, or even at the roofline several floors above, the water will follow the path of least resistance and exit the wall wherever it has the ability to escape, even if that escape point is several windows to the side and/or on a different floor.
Retrofit windows will NOT solve pre-existing leaks. If you have a window that is leaking water between the frame and the wall, you will need to use a Nail on Frame window and a general contractor so that new flashing can be applied, and the stucco or siding can be re-applied to seal the gaps. If a retrofit window is used, it will simply trap any water in the wall until a later date when it will have caused additional damage including mold and other safety and/or unhealthy situations.
To determine if it’s the window to blame, or if your water intrusion point is coming from somewhere else we suggest a proper water test :
While one individual is inside the home watching the frame of the window, a second individual would gently spray water around the frame in the 2-3”shaded area on the image below, starting at one edge and slowly and gradually moving the water from one side of the window to the other over a 15-20 minute minimum. Do not spray water directly on the glass, or use a power sprayer as that will void the warranty on your dual pane seal, and can cause leaks to be created as a power sprayer has enough force to break the sealants previously applied. The goal is to re-create rain and weather conditions, without forcing water which would enlarge hairline fractures too small for the average eye to see, and to re-create the water intrusion to identify the point of entry. If spraying in this manner does not re-create the issue – that window is not the culprit and it’s time to spray other points on the wall until the true intrusion point can be found.