# OSB Water Damage Repair



## HooKooDooKu (Jan 7, 2008)

Had a water leak that took years to detect, and a few years to find and fix the cause. The leak resulted in the rotting of some OSB located between a 2x4 studded wall and a brick venier. 

I'm now ready to finish the basement room where the OSB damage is located. I'm looking for some ideas on what, if anything, I need to do in the way of repairs before this wall gets insulated and sheet rocked. Note that the damaged OSB goes farther up the outside wall than you can see from the image.

All of the rotted OSB has been ripped out, so what OSB you see is solid. Behind the OSB you see some of the house wrap and flashing from the deck above, as well as some of the caulk-like material used to seal around the flashing when I thought that to be the source of the water (it wasn't).


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## Gary in WA (Mar 11, 2009)

1. The rest of the OSB looks OK.

2. Add two studs under the doubled joists for direct bearing. 

3. Fire the lazy electrician. How will you drywall that, or even fire-stop it at the doubled top plate?

4. Stagger nailing from side to side, never in a straight grain line. (A lot stronger, too).

5. Very hard to replace sheathing above the plate with a deck there..........

Be safe, Gary


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## HooKooDooKu (Jan 7, 2008)

1. Because it took years before the problem showed itself, it was easy to deliniate between OSB that was sponge material and what was still sound.

2. The doubled joists are the start of a cantilevared fire place. They are doubled up as a part of framing the joists for the fireplace that run perpendicular to the rest of the joists in the room (i.e. it's not doubled up because of the load above it).

3. Unfortuantely that's how they wired this house when it was built. Other than stubing in for a bathroom, they didn't put much thought into what was going to have to be done when someone went to finish in the basement. I've got to build some soffits on the left and right sides of the room for HVAC ducts. I've considered going all the way around the room with soffits and give the whole room a tray-ceiling look. So the wires would be in the soffit.

4. ???

5. Yea, just plain all around it's going to be nearly impossible to "fix" without some ugly demolishion. 

The best idea I've been able to come up with is just plain not attempt to repair anything and just plain fill the space with expanding foam before using standard R-13 insulation to insulate the wall. Off the top of my head, I can't think of anything structurally deficient just because around 1+ sqft of OSB sheating is missing. The area is "protected" from the outside with a brick venear. FWIW, this wall is 100% above grade as a part of a daylight basement.


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## Big Bob (Jul 27, 2007)

Be sure you run a hose and test your water barrier before you foam.


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## HooKooDooKu (Jan 7, 2008)

Big Bob said:


> Be sure you run a hose and test your water barrier before you foam.


The flashing that solved the leakage was done more than a year ago. Haven't had so much as dampness in this area since. And we've had some rain since then too, so much that we had a flooded basement for the 1st time in over 10 years of home ownership (and the gutters have since been diverted via 4" drain pipe).

However, those rains did show that the OTHER corner from where this damage occured needs the same repair.


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