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Community and Q&A

Basement Waterproofing

azad_lassiter | Posted in GBA Pro Help on

Builder/Developer in Minneapolis MN. I purchased a 1950’s ranch house with an unfinished walkout basement. The basement foundation is 12′ block  There were no gutters and the grade was not great. I installed gutters and helped the grade out first. My guess is there is no perimeter drain No sign of dampproofing either. I tapped plastic to the walls and floor and left for a few weeks to see if any moisture built up. None did. My moisture meter still reads high contents of moisture in the walls and floor. 

Exterior drain tile and interior drain tile seem out of my budget at this point. 
But I would like to finish the basement. and my plan was as follows.
-3″ EPS (recycled from a commercial roof) foam insulation on the interior of the basement wall. Either glued or plastic foam anchors. Probably tape foam.
-furring strips nailed through to block wall
– wallboard probably drywall. 
– vinyl plank or carpet floor. 

I had thoughts of using a dimple mat on the interior of the walls and floors. But without a place to divert the water, It doesn’t seem like a valuable use of funds.
Any other recommendations for interior coatings or how to keep it dry without the use of exterior or interior draintile. 

Thanks in advance.

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  1. Expert Member
    NICK KEENAN | | #1

    You have to give the water somewhere to go. If you don't, it will find it's way out somewhere on the wall eventually.

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