Persistent leak around window

Old 04-27-08, 03:42 PM
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Persistent leak around window

I am not sure if this belongs here or under the "Walls" thread. So if I am wrong if a moderator can let me know and I'll move it.

Anyway, I have a small but persistent leak around a window in my dining room that I have been unable to fix. The exterior of my home is brick. The break area right above the window is laid in a herringbone pattern with alternating courses of bricks at 45 degree angles. The wall is about 6 feet high running from the top of the dining room window to the bottom of a bedroom window above. The course of brick above the window is set vertically.

The window is a vinyl clad, double pane, relatively new as the home is only 4 years old. The leak is coming in to the best I can see at a point new the center of the window. I have removed the casing and cut a small piece of drywall out that allows me to see the edge of the window.

Of course on the first place there is a huge gap between the framing and the window sill. (The guy who built this home apparently has a bad reputation and is now bankrupt). The water leaks in only after a hard steady rain. I have taken the hose and sprayed the area. I have managed to located the leak somewhere in the first 2 feet above the area where the small leak occurs.

It is not a strong pouring leak, but more of a steady drip. I had used clear silicone caulk all around the window, but this did not fix the problem. I went back and used clear flashing cement used to bond flashing to brick. I filled every gap among the window edge and the metal sill piece that supports the first course of brick above the window.

I can only assume the water is seeping in through the brick or mortar above. To remedy this, I plugged every small gap or crack that could be seen by the naked eye, I also covered the entire wall above the window with 2 coats of liquid masonry sealer. But I still have the leak.

I am at my wits end, I cannot seem to find and plug this leak. Any advice would be greatly appreciated before I lose my mind.
Old 04-27-08, 04:48 PM
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I've read your message several times and am not real clear on exactly where the leak is occurring. Since you refer to it as a drip, I'm guessing it is occurring at the top of the window, not the bottom. Removing the casing (window trim) from the window would help you find wet insulation and maybe track down the spot at which the leak is entering the rough opening.

My first suspicion would be whether or not the window ABOVE this leaking one is completely sealed up or not. Often water will get in way up high and travel down the building paper behind the brick and then run behind the nailing fin of the lower window and appear as a drip on the top jamb of the window.

The water could be coming in around that window, or through the sloped brick sill below it (that is, the brick sill ABOVE the window where the leak is showing up), or it could be seeping through the mortar anywhere inbetween. Contrary to popular belief, brick is not waterproof. If you say you can make the window leak by spraying water on the brick, I would certainly assume the latter is the case.

Sealing the brick might be all that is needed, but if there is an obvious crack in the mortar (like a ledge or crack where your keystone blocks make their way over the window), you'd want to get that repointed. In either case, a mason would give you the best advice.

The reason water is finding its way into the window instead of continuing on down the building paper comes from poor window installation techniques. The top nailing flange of any window ought to be flashed so as to shed any water that happens to come down onto the window from above. In other words, even if your house had no brick on it, those windows should not leak. Of course, those are today's standards for window installation and you would not expect an older house to meet such high standards. If the house is new... well then that's another story.

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