I'm looking for some ideas on where a leak problem might be in our house (mostly because I'm not sure about how concrete block walls are constructed). We have a block house in FL built in 2001 (well, block up to the bottom of the roof line then wood sheathing covered in stucco on the gable ends of the house).
*** The Problem: One of the windows on that wall was leaking water from above it. This happened once before, but only in the same circumstance -- when we have a tropical storm and wind-driven rain is driven at this side of the house. The wall is very tall there as the peak of the roof is straight up from this window (there's about 10 more feet of flat wall abovce this window).
*** My Diagnosis (so far): Anyway, we noticed water dripping in though a hole in the sheetrock used to mount a vertical blind rail. In order to diagnose it better, we removed sheetrock above the window to see the source. The window has a pre-cast lentil above it spanning the window and block all around it. There is at least one course of block above the lentil that I can see (I only removed enough sheetrock to see the start of the leak. Some fo the mortar joints had small holes (approx 1/8") that seemed to be where the water was seeking its way inside.
Looking at the lentil, it has blocks on top of it and there is mortar between the sides of each block and under each block (between the block and lentil). During heavy wind-blown rain against that wall, water is "streaming" from the vertical mortar seams between the blocks above the lentil, and seeping through the horizontal mortar seams between the lentil and the block above it. The problem here is that once it gets onto the house side of the block it gets the sheetrock wet, etc.
We also went into the attic and looked at the roof and wall above this window -- nothing. Everything is dry as a bone during the middle of the storm while the window is dripping. I can't see the top of the lentil from the attic, though, There appears to be some horizontal wood down the wall above the lentil blocking it's view. But everything I can see as far down the wall as I can see is all dry, as well as the roof and attic insulation.
*** What about this? On the exterior wall where this window is we can see some type of horizontal "joint" that stretches the width of the house, about 8 feet up. We think it's either some type of expansion joint or perhaps a weep screed, but I've not heard of weep screeps up that high. In any event, It seem that this joint might allow enough water to enter behind the stucco and (somehow) into the block, but we can't be sure. There must be a lot of water pooling in the hollow block above the lentil because it is dripping at a very fast pace. If you wipe it away it starts streaming again immediately. I event tried squishing rubber silicone sealant onto the holes in the mortar (from the inside) just to temporarily plug the entry point, but the water seeped either through it or around it and still came in at the same pace. It must be a lot of water in there!
We looked for stucco cracks and saw a few "hairline" (at best) cracks running vertically above the "joint" for about 3 ft. in length, but I wasn't sure that such a fine hairline crack would let enough water in to let it get inside the block and drip out like a fast-dripping faucet.
I was half-temped to drill into the block above the lentil just to see if it drains out and see how much water is in there, but I won't dare for fear of making the problem worse! <g>
Can anyone think of what might cause this much water to get inside the block such that it is seeping into the house through the mortar? I've heard it's normal for some water to get behind the stucco, but I thought it was supposed to run down the outside of a water barrier and then out the weep screed (which I thought was at the bottom of the wall). Is it normal for water to get inside the conrete blocks that make up the wall? If so where should this water go when it hits a solid lentil? I'd greatly appreciate any ideas anyone might have as to why something like this might happen.
Thanks, -- Vinnie