Looking for advice on a damp corner

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Feb 27, 2014
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Hello all!

Last weekend, while removing an old carpet in a den in my basement I discovered that the cedar plank in one of the corners was discolored. I removed a few planks and found that the corner was very damp. The 2x4 joist was saturated and the insulation was nasty and stinky. The joist is still strong, but about 1/8'' -1/4'' of the outer wood is rotten and soft. This wall is a cedar plank wall and is above the ground level. The adjacent wall is brick, and the bottom 3 feet of the brick wall are below the ground level. The dampness is in the bottom corner where the two walls meet. The cedar wall is on a concrete slab. Directly outside is a brick patio. Regretfully, the patio is on about the same level as the slab.

I am attaching a few pictures of this corner from inside and outside of the house.

I suspect that the water in the corner could enter from the patio. The patio has good drainage. Even during strong rain, there are no standing paddles. But I suspect some water could collect at the corner. Alternatively, it could seep through the brick, but that wall is in the middle of the house and appears dry - the only wet spot is the corner.

Is there a way to protect a wall when the slab is on the same level as the outside? Should I add a trench around the outer perimeter or a plastic barrier? Could the water come through the brick? What should I do in this case?

I appreciate your expertise and feedback!


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Unfortunately, no matter the pitch of the patio, water's going to get through the bricks and the joints between bricks. It could wick into the wall material and end up indoors. This might be a tough one to solve without tearing things up and digging down to waterproof.

Maybe try urethane caulk at the patio-to-wall joint outside. It may or may not help.

We have a brick patio and the water that gets through the bricks & joints migrates to the wall because it's dryer. Some ends up indoors. Caulking helped stop the weeping indoors only to a point. After big rains, light dampness still shows up inside.

Water always wins!

When you solve it, please post back so we all can learn.
We have a similar issue. It of course won't stop all of it but we use a simple sandbag at the exterior wall. You could try that until you can find something permanent. The softer the bag the better it will conform. We put play sand in a white kitchen trash bag and it takes shape well. A sand bag requires your attention though because after it rains you need to pull the bag away so that everything can dry out.