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Sealing basement concrete

thegiz | Posted in General Questions on

So I have been doing some research and came across some suggestions for basement dampness and you guys are smart so you can tell me if this is BS.  So I attached a picture below, I basically have constant dampness on the floor in this one area, never sitting water, just damp to touch.  I attached a picture to see.  I have a perimeter drain on exterior wall, but it was already there before I moved in so don’t know if it stopped working.  Basically floor has a lot of deviations and needs a new level surface.  So I want to skim coat concrete with self level and seal the **** out of it.  Many products claim they can waterproof concrete, radonseal, Armor seal, dry plus, etc.  Will I be doomed with mold.  I figure after sealing best product would be ceramic tile over, I would think more damp proof than lvt.  Maybe throw on some cheap area rugs I can throw out if and when they grow mold for comfort.  Walls would be exterior foam, wood framing filled with unfaced insulation and drywall cover.  I’m in climate zone 5.  I can afford around an inch if I need to make floor higher.  Thanks in advance for answering my ridiculous questions.

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  1. walta100 | | #1

    In my opinion the only real long term solution is a working drainage system. Any attempt to paint the concrete on the inside is doomed to fail if you have 8 feet of standing pushing in on the paint.

    The first questions are your gutters clean and working? Does the ground and pavement slope away from the house? Do you have troughs and extinctions on the downspouts to carry the water away from the house? Those are the cheap fixes if they fail you need a big fix.

    The best system is on the exterior drain at the footing installing this after construction will destroy your landscaping and is very expensive.

    The next best system is a drain around the inside of the walls leading to a pit with a pump to remove the water.


  2. Jon_R | | #2

    +1 on reducing the amount of water that is under the slab.

    Also consider overlaying with foam, concrete board and then tile (although this adds up to more than an inch).

    Keep basement humidity low (ie, a dehumidifier) and rugs will be OK (I have a carpeted basement with a nominally dry floor).

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