Window Leaked - Now Siding Problems

Old 01-08-08, 10:14 AM
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Window Leaked - Now Siding Problems

I have a window on the 2nd floor that has a leak -- we noticed as the wall board had a bulge that felt wet and then it dissipated. So the water traveled somewhere inside the wall.

We later noticed the siding on the exterior almost immediately below the window on the ground level has a significant bulge... a poster on the 'interior' forum for windows has suggested that the underlying material has probably swelled due to the water.

Any suggestions on how to attack the repair?

We will be caulking the window once it stops raining (duct tape in the mean time) but I don't know anything about siding. I"m trying to decide whether I should DIY or pony up some $$ and hire it done.

The siding appears to be a wood or composite product, not vinyl.. my home is about 12 years old in northern CA.


Thanks to all...
Old 01-08-08, 03:33 PM
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Think of your home's windows as 'Vertical SkyLights'. Water gets at the sides and tops of them. The water must have a way to exit from the siding. Ever notice how SkyLights on the roof have the lower flanges/flashing exposed so water can escape? The same holds true with regular windows.

Here are pictures of window flashing. Metal used should be no less than 30 long x 14 wide. Notch out a 4 wide x 24 long piece.

For these pictures, I used a display window inserted into a faux wall and I omitted the insulation board, Tyvek and tape. I used duct-tape to prevent water from getting behind the flange, same as way Tyvek tape would be used in a real installation. DO NOT OMIT THOSE STEPS!
The left side of the window was installed the way most builders and siding installers do it. See how the water goes directly BEHIND the siding. You must depend on the Tyvek, felt or any other covering to never let water into them. Or rust nails. Or wick into the sill plate. These covering are supposed to be the SECOND line of defenses against the weather!
On the right side of the window, the water exits ONTO the siding and NEVER reaches the Tyvek, felt or any other covering! This is how the siding becomes your FIRST line of defense against the weather.

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