I would appreciate any tip, help on diagnosing the symptom below.

Been searching online to help diagnose symptom of "wet patch on exterior wall after rain". Did find several useful resources, notably this post,

Basement walls above grade are wet outdoors

I've been noticing on my exterior walls above the grade are wet, after rain.

I've checked all gutters and they look fine, no clogs.

Inside basement walls are dry, i don't suspect mold (yet).

Just getting started to understand this symptom better. I'm wondering if the mulch to the sides of the exterior wall is adding to the problem.

As mentioned in the post referenced above, i'm going to follow up these 2 tips,

There could be two issues: 1) moisture dripping off the building paper under the siding, or 2) moisture entering the masonry cells.

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How looks after dried,

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What got me scratching my head is, comparing my exterior wall to adjacent neighbor, my side seems more wetter, seen same time, same day after rain, in a cloudy (no sun) day.

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  • Hello, and welcome to Home Improvement. Why isn't it just rain hitting the concrete? And, you should probably take our tour so you'll know how best to participate here. – Daniel Griscom Dec 10 '19 at 16:50
  • Hi, yes, "why isn't it just rain hitting the wall". Then got me thinking how is it that both sides of the outside wall, my sides seem more wetter than that in both sides neighbor walls outside. Hrm... And yes, i'm taking that n00b tour. :) – dinan5m3 Dec 10 '19 at 17:25
  • Do you realize if the ground is damp the wall will wick moisture. Do you have a moisture issue you are trying to solve? Damp concrete outside is totally normal. – Ed Beal Dec 10 '19 at 19:58
  • Yes, i'm realizing that damp ground can cause the wall to show moisture. I don't believe i have moisture issues at these walls. Frankly i maybe overreacting. I believe reason i'm at where i'm with all this is because the neighbor walls show dryer color. Why would that be? – dinan5m3 Dec 11 '19 at 3:21
  • Having moisture retaining mulch around the perimeter certainly is not helping the situation. I bet replacing that with gravel will drain most of the water before it has a chance to be wicked-up by the masonry. Of course, that may create another issue at your downspout. – peinal Dec 20 '19 at 16:55

Get out when it really rains and see if the rain just hits the wall. I bet that's it. Nothing to do. Remember concrete is porous and sucks water.

  • Okay, will do, and there are rainy days in the forecast. I've looked more closely i'm wondering the differences in the painting/coating "color" on the concrete between mine and neighbor is at the root of showing up differently. Just bizarre. Perhaps my walls have color that makes mine to appear "wetter" (damper). Upon touching the wall, the wall "feels" dry to touch. – dinan5m3 Dec 12 '19 at 4:19

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