Hey everyone. This is my first post. I am a first-time homeowner and have lived in my house for almost 6 years. Ever since I moved in, I have had this annoying leak (rain water) in my 1st floor office. The problem predates my ownership of the home because I noticed old water stains in the office a few weeks after moving in. As you can see in the pictures, the leak is directly in the corner of the office where the ceiling meets the wall, so I'm 100% sure the leak has nothing to do with the office windows. Here's the problem: every once in a while (maybe once every 1-2 years, if that) when it is windy and it rains very hard and sideways (hitting the rear of the house with the windows), I will notice that the corner of the ceiling/wall in the downstairs office is wet/damp from rain water. It doesn't happen every time it rains, just when it is very windy against the south side (rear) of the house. I originally thought the windows in the guest bedroom directly above the office was the culprit (they were very old), so I replaced the windows in 2014 with brand new triple-pane windows. However, a few months after putting the new windows in, I noticed water again in the office! I called the window company that installed the windows back and explained the problem and they caulked extenisvely around the windows and I haven't noticed water again for almost 4 years, until last week when it rained very hard and sideways.Naturally, I'm frustrated and stressed out that the problem "came back" (although I'm convinced it never went away, just that it hasn't rained the "right" way), so I called the window company and they're sending someone to take a look at it on Wednesday, but I'm not confident they know what the problem is or will spend the time to truly diagnose the issue. So today, I woke up anxious and fed up, and wanted to find out for myself where the water intrusion is coming from. I hooked up a garden hose and sprayed the house/siding in sections, starting from directly where the ceiling/wall corner of the office would be, and moving up towards the upstairs guest bedroom. I originally suspected the problem may be the bottom of the upstairs window aluminum capping where it meets the siding (looked like there was some space there), but turns out it wasn't that. After almost 2 hours with the garden hose (being meticulous to hit it in sections and then run inside to inspect for water), I finally hit a particular part of the upstairs window and, BOOM, I instantly felt water in the office. It was actually the worst water I've ever seen in the office because I suspect the angle I was spraying the garden hose (from the ground up) is an unnatural angle for rainwater given the overhang of my roof which protrudes out over that window. It turns out that when water hits the TOP of the upstairs window (see last picture with diagram), it gets into the house and runs all the way down the side of my house to the office. Interestingly, I dont see any water whatsoever in the upstairs guest bedroom (wall, floor, etc). I went upstairs and reached outside of the upstairs window and tried to stick my hands/fingers in that area above the capping to see if I can tell what the problem is but my inexperience with window capping/channels/etc has no idea what they are feeling. What can I do to permanently fix this problem? Tell the window company to fix it? I kind of want to take matters into my own hands and do it right! I need help!P.S. I have an identical situation on the right side of the house (same windows/capping) but I've never noticed water in my kitchen on the first floor but I kind of want to do whatever I end up doin on the left side to the right side to ensure I never have this issue on the right side.http://bit.ly/2DzU37P via /r/DIY http://bit.ly/2FREZoG
