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Cinder block basement walls, sealing and painting?

Hello! This is our first time owning a home with a basement, and we have a lot to learn. I will start with the history, explain our hopes and plans for the basement, then move into the question and concerns. Feel free to skip to the question. The history and plans are here for your context if that info is helpful.

HISTORY: So, during the inspection, there was mold found in the basement of the 1953 ranch. The mold seemed to be clearly related to a bathroom leak that was also found. There was also efflorescence on the cinder block walls in several places, and it was unclear whether we had a "wet basement," but there was no sump pump, and the agent insisted that it was not. The inspector said that the assertion was plausible--that there was a "damp" problem that could be addressed with a dehumidifier. We had the leaks repaired and a very thorough basement mold remediation completed. After moving in and living there during a very rainy summer, we noticed water pooling up in certain areas of the basement after a big rain. So, we set out on a mission to get the moisture in the basement totally under control.

We live near the top of a significant hill (there is one row of houses about 200 feet above us, and two rows of houses below us to the bottom of the hill). So, it is unlikely that we are below the water table and more likely that we are dealing with runoff from the hill. We installed an exterior drain at the base of the hill near our house to help direct runoff around the house. We also checked the gutters during the next big rain, and found them to be lacking. We had them repaired and replaced and they all carry the water far from the house now. We sealed a patio near the house with polymer sand to facilitate runoff away from the house. We replaced the very old windows, and purchased a nice dehumidifier. We were working on regrading the soil around the house, but the winter cold has halted our progress for now in that department. We will complete that soil work the next time we are off with a couple of days of decent weather. Our humidity in the basement is now measuring at or below 45% and it smells nice and sweet down there! There has been no more evidence of water pooling since the gutters were repaired in August (5 months ago).

OUR PLANS: This is a little difficult to describe, but the basement is 1/2 crawl space (on the upper part of the hill where they likely hit bedrock, and 1/2 full basement. The full basement side has the laundry, utilities, and the freezer. My husband also has an area dedicated to workout space. We don't want to "fully finish" the basement, but we would like to finish it to a clean kind of "industrial look." We envision a kind of sealed concrete or epoxy floor, and painted cinder block walls and matching painted ceiling. We plan to start with cleaning and painting the walls, and that is where our question comes in.

THE DILEMMA: My contractor and the mold remediation provider have both suggested Dry Lok-ing the walls to get us toward our goal. I researched the pros and cons of this approach and found reasons for concerns. People complained of peeling off the wall and other kinds of problems. But, the biggest concern I have found ****** is the suggestion that the Dry Lok would degrade the strength of the foundation wall by holding the water in. The mold remediator suggested that was an unfounded concern for our case. He said that if there were water in the wall that it would eventually work its way out through the footer and move along on its way. And the contractor assured me that the people with problems with the Dry Lok probably had wet basement issues that the Dry Lok could not cope with. He also suggested the importance of the Dry Lok being properly applied.:confused:

In all this research, I have also found some information about "Sodium Silicate" products like VSeal and Foundation Armor. These products claim that they have a lifetime gaurantee (instead of the 10 year Dry Lok gaurantee) and that they actually strengthen the walls by 45% by reacting and binding with the materials in the cinder block. There is not plentiful information on these products ****** like there is about the Dry Lok, but there doesn't seem to be any valid complaints either other than the "you have to let the water out of the block or it degrades the foundation," which is the same complaint from the Dry Lok by some people which has been negated by others. :confused: My contractor had never heard of Sodium Silicate and he is very reputable and been doing full on whole house and addition construction for ten years.

QUESTION: So, can you please give me feedback on my questions and concerns? What do you think about this process?: Clean and prepare the cinder block according to the instructions on the sodium silicate product label, seal the wall with the sodium silicate and then paint with masonry paint.

Has anyone heard of any of the Sodium Silicate products like VSeal or Foundation Armor? There are other products that seem to be similar--Radon Seal, Ion Seal Armor and Concrete Searler X-2 by Stone Technologies Corp. Thanks in advance for your feedback and input! :)


Re: Cinder block basement walls, sealing and painting?

You may can check on the following products.
Thoroseal foundation water proofing
KEIM this one comes in colors
Applied Technologies.
I have used Xypen interior below grade with a cement plaster finish no problems. Also used it on Exterior walls over new CMU than Stucco was applied this was over 20 years ago no problems to date.
Thoro Seal I have also used this product many times for Interior walls below grade to include elevator pits.also have applied gypsum plaster over this product.
Have used the KEIM products on the exterior above grade only you can get a better finish with this product than with the use of only Xypex or ThoroSeal

Re: Cinder block basement walls, sealing and painting?

Regarding paint of a below grade block wall, I have had good results with DRYLOCK paint to keep out moisture.
There is a sub-floor system that allows moister/water to flow under it with out affecting the flooring on top. I believe this is called DRY CORE.
Good Luck with your projects.

Re: Cinder block basement walls, sealing and painting?

I also have had good luck with Drylock - but only to a certain point. After the water gets so high nothing will hold it back.

Re: Cinder block basement walls, sealing and painting?
HoustonRemodeler wrote:

I also have had good luck with Drylock - but only to a certain point. After the water gets so high nothing will hold it back.

Agreed. As long as moisture isn't too bad, DryLock works well. If there's more moisture than that, don't seek a 'better product' but fix the problem allowing the excess moisture.

Water kills houses and has to be kept outside of them where it belongs. Fail to do that and nothing will help save the house, and this is a lot more important than any aesthetic considerations.


Re: Cinder block basement walls, sealing and painting?

I wanted to thank everyone for your feedback and help. The product suggestions helped my research. I really like the look and description of the Kiem paints, and I had not encountered them or many of the other products mentioned.

We have kind of typical dehumidifier controlled "dampness" more than wetness now that we have the runoff directed away from the house. I think that the walls will do well with something that is sealing and breathable, like the Keim paints seem to be.

Thanks again for your help!:cool:

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