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Discussion Starter · #1 ·
I have a concrete block unfinished basement. I noticed during the last 2 rainfalls that 2 spots in my basement walls looked a bit dark (see attached pictures).

They both are around the mortar. When I touch them, I can feel the dampness on my finger.

Once the rain is gone, the spot by the window clears up, the other spot stays dark for a lot longer. For the 1st picture on the other side is mulch. For the 2nd picture there's nothing on the other side. It rained the other day and I went outside and the downspouts seems to be functioning fine.

I understand that concrete is porous, but is this normal of concrete?

Thanks in advance for any feedback.
 

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Look at the outside and figure out how water is getting in. Cracks in the mortar, holes for utilities not sealed, no flashing where siding meets foundation, ground around foundation not properly graded, bad gutter design, etc.
 

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Discussion Starter · #4 · (Edited)
Here's pictures of the outside

1st Spot
On the outside wall is just a bunch of mulch, shrubs, and plants. There is a downspout and when it rained the other day, I went outside and saw that the water was entering the black spout extension. So I'm not sure what else to check.



2nd Spot
This spot is right near my basement window, the spot on the inside which was damp was actually not even at ground level. I circled the spot in the picture where it was damp on the inside.

The only thing I can think of is, if you look north of where I circled there is a little settlement crack on the exterior foundation. Could that be a possible reason?

Edit: I realized that the pictures might be too small due to the re-size. Here are external links:

1st spot:https://drive.google.com/open?id=0B91PleEPCKuIRmNxX3BucTJxOVk

2nd spot: https://drive.google.com/open?id=0B91PleEPCKuIWElGaVJ5YjRYc1U
 

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I have a concrete block unfinished basement. I noticed during the last 2 rainfalls that 2 spots in my basement walls looked a bit dark (see attached pictures).

They both are around the mortar. When I touch them, I can feel the dampness on my finger.

Once the rain is gone, the spot by the window clears up, the other spot stays dark for a lot longer. For the 1st picture on the other side is mulch. For the 2nd picture there's nothing on the other side. It rained the other day and I went outside and the downspouts seems to be functioning fine.

I understand that concrete is porous, but is this normal of concrete?

Thanks in advance for any feedback.
Water is getting into the cavities of those blocks, thats why you can feel it, and the reason the one stays wet longer.
 

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you don't have concrete - you have a cmu (https://www.google.com/search?q=cmu+wall&ie=utf-8&oe=utf-8) wall,,, probably the main reason you have wet spots is the builder's reliance on the bldg code which specifies a 3mil coat of dampproofing material,,, it does NOT require waterproofing

mortar is more porous than cmu's - cmu's are extruded & vibrated for better consolidation than mason's mortar into which no waterproofing agent has been added

there is no easy remedy
 

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Discussion Starter · #7 ·
you don't have concrete - you have a cmu (https://www.google.com/search?q=cmu+wall&ie=utf-8&oe=utf-8) wall,,, probably the main reason you have wet spots is the builder's reliance on the bldg code which specifies a 3mil coat of dampproofing material,,, it does NOT require waterproofing

mortar is more porous than cmu's - cmu's are extruded & vibrated for better consolidation than mason's mortar into which no waterproofing agent has been added

there is no easy remedy
I see, then why would only certain places have wet spots and not everywhere?

Would the wet spots deteriorate the mortar over time?
 

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because water takes the path of least resistance,,, there are 3 other rules:
1, it runs downhill;
2, it rushes to fill avoid (try making a hole in a tub full of water);
3, it seeks its own level

mortar does degrade after long exposure to water which contains acids - airborne OR otherwise - ever hear the term 'repointing' ???,,, this is why waterproofers have bigger boats

IF you're in your early 30s, its likely the house will outlast you IF its a new house
 

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Discussion Starter · #9 ·
because water takes the path of least resistance,,, there are 3 other rules:
1, it runs downhill;
2, it rushes to fill avoid (try making a hole in a tub full of water);
3, it seeks its own level

mortar does degrade after long exposure to water which contains acids - airborne OR otherwise - ever hear the term 'repointing' ???,,, this is why waterproofers have bigger boats

IF you're in your early 30s, its likely the house will outlast you IF its a new house
The house was built in 2011. Even though it may take a long time for mortar to deteriorate. I guess it's still best to find out where the water might be coming in from.

I've checked the downspouts which seem fine. Is it worth it to dig up 3 feet of munch and dirt to make sure there's no crack on the other side of the wet spot?
 

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The presence of effervescence is a big clues. Before you drive yourself nuts looking for a water entry point, do a little research on water wicking and capillary action.

Capillary action is when water has the ability to travel up against the pull of gravity through a porous material. Once water that is drawn up by capillary action finishes its job, it evaporates, leaving behind a residue of salts, or effervescence.

The only way to stop capillary action is to place a barrier between water/moisture and the porous material. Most people think if they use a waterproofing material on the interior wall, it will stop the problem. Your wall will be dry to the touch for a while, but the capillary action will continue within the porous material. Exterior waterproof is the best method.
 

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Discussion Starter · #11 ·
Thanks for the reply Missy Brown.

I've had 2 people look at the effervescence, and both said its not a problem.

The 1st (home inspector) said it's normal and probably occurring because down spouts weren't extended.

The 2nd, a basement waterproofing person also said that effervescence is a normal occurrence.
 

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A property sealed wall (exterior sealed) will not leak or effervescence. If you finish basement or have item against that wall, it will absorb that water. You need to water proof from outside and this is not normal for a home!

It needs addressed and fixed
 

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Discussion Starter · #13 ·
Thanks,

What kind of contractor can I call over asses the situation in person. I'm hesitant on a general waterproofing contractor because they have a vested interest in getting work.
 

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unsure why you'd think that way but an electrician would be good as he won't care/know about the work,,, i wouldn't call a carpenter or plumber as they MIGHT want it but not know how or why,,, 2 other fairly safe choices would be an asphalt paver ( driveway ) or a HVAC guy

i always like to call someone who knows what to do to solve our problems but that's just me
 

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Discussion Starter · #15 ·
Thanks stadry,


Don't get me wrong, I want someone who is going to know how to fix the problem as well, but my perception with contractors is that they will give you advice but it may be bias because they stand to profit from it.
 

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we do this work for a living,,, the waterproofer you called is correct in his assessment that ' EFFLORESCENCE ' is a normal occurrence - normal result of builders following the bldg code - like union workers' pay schedules, his advice follows the lowest common denominator,,, IF he know how to mitigate the problem, he would've offered a solution

you're received the correct solution in this thread - now YOU have to find someone to do the work UNLESS you're good at digging down to the footing & finishing the job correctly
 

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I understand the drainage around the house, but based on the pics, it appears that the wet spot by the window is above grade. Need to find the source of that
 
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