Painting unfinished basement wall and concrete slab floor

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Old 04-28-16, 03:50 PM
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Painting unfinished basement wall and concrete slab floor

The basement is unfinished, and there's some visible flaking on the current paint on the walls from what looks like to be water damage, particularly under the windows. Haven't had any problems with wet walls recently, but the house hasn't been waterproofed and is old, so I'm sure the walls do get wet from time to time.

There's also no flooring: just a concrete slab which has already something on it, but I don't think it's paint... or maybe it is.

Anyways, how do you paint such a basement? Do I have to paint the walls with permeable paint or the opposite? Would I prime it with a waterproof prime or not?

Same question goes for the floor. Thanks.
 
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Old 04-28-16, 04:06 PM
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So far we have no pictures so we can see what your seeing.
No way is paint or any form of sealer going to to stay stuck to a leaky wall.
Basements need to be sealed from the outside.
Grade running away from the foundation, no mulch piled up against it, gutters with down spouts running away from the foundation, no flower beds and landscape timbers forming ponds.
 
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Old 04-28-16, 08:35 PM
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Yeah, I have a general idea about "waterproofing". Most of the stuff is in order. 90% of the grading is away from the house (except for maybe a small patch in the asphalt driveway), down spouts and gutters are OK, etc. The foundation isn't waterproofed, and I don't think there are any weeping tiles, and there aren't any window wells. But anyways...

I had heard that permeable paint won't come off if some of the walls are wet. Maybe I heard wrong.

I'll take a video tomorrow and post it.
 
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Old 04-29-16, 04:31 AM
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Are the foundation walls poured concrete or block? the latter [and bare/not previously painted] requires block filler primer if above grade or drylok when below - but as Joe mentioned, waterproofing should always be done on the exterior!

Haven't had any problems with wet walls recently, but the house hasn't been waterproofed and is old,
When were the walls last wet? Are you sure there is no waterproofing on the exterior side of the foundation? how old is the house? Do you intend to finish the basement or just trying to brighten it up?
 
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Old 04-29-16, 09:36 AM
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Are the foundation walls poured concrete or block? the latter [and bare/not previously painted] requires block filler primer if above grade or drylok when below - but as Joe mentioned, waterproofing should always be done on the exterior!

When were the walls last wet? Are you sure there is no waterproofing on the exterior side of the foundation? how old is the house? Do you intend to finish the basement or just trying to brighten it up?
The walls were last wet maybe two years ago. And by wet I mean noticeable wet by touch/eye. I did an inspection report in September of last year and the inspector said one wall was wet when tested. But if you touch it or look at it, you won't know.

Foundation is concrete block.

I am not sure there is no waterproofing on the exterior side. I asked the previous owner, and he said he doesn't think there is one. House is from the 1930s.

I do not intend to finish the basement at this time. Probably in 2 or 3 years. At this point, I'm just trying to "brighten it up", as you say. Or in my own words, make it look less like a torture chamber.

What do you mean 'if below grade, if above grade'? You mean if the basement is underground? It is. The lowest part of the basement windows are on the same level as the outside (one window is even below grading, for some odd reason). The basement floor is almost 5 ft below the outside.
 
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Old 04-29-16, 10:04 AM
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Unpainted block requires a block fill primer to fill the pores in the block and keep the paint from seemingly soak thru to the other side. Whenever the block is below grade [has dirt on the other side] it's prudent to use Drylok. This more for insuring a good paint job than for waterproofing.

I would assume if there wasn't any waterproofing on the exterior side of the foundation you'd notice dampness [or worse] every time you got an inch or more of rain.
 
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Old 04-29-16, 01:22 PM
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Unpainted block requires a block fill primer to fill the pores in the block and keep the paint from seemingly soak thru to the other side. Whenever the block is below grade [has dirt on the other side] it's prudent to use Drylok. This more for insuring a good paint job than for waterproofing.

I would assume if there wasn't any waterproofing on the exterior side of the foundation you'd notice dampness [or worse] every time you got an inch or more of rain.
I'll post the video/pictures tonight, but there is visible paint damage (even a bit of mould in one area), but I haven't had an issue since I purchased the property 3 years ago. Which I guess is strange, because the grading on one side (the dirt side as opposed to the driveway) is just terrible, but nope, haven't had an issue.
 
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Old 04-29-16, 02:01 PM
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The thing that's confusing me here is that it sounds like you're advising me to put an impermeable primer. Wouldn't that just create a wet block (if there really is a water issue) that will take forever to dry, and hence damage the foundation/create mould? I thought I had to use an vapour permeable paint.
 
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Old 04-29-16, 03:17 PM
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Ya, it's hard to pick the right answer Bare block needs blockfill or drylok as a primer, if water comes thru blockfill it will lift/peel. Unless there is a tidal wave behind the block - drylok will prevent the moisture from coming thru ..... but keeping the block saturated with moisture is bad for the block.
 
 

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