Turn damp spaces into usable square footage by waterproofing cinderblock walls. The waterproof walls can then be painted any color of your choice of covered with paneling or sheetrock.




First, here’s what you’ll need to do this job:

– Hydraluclic cement

– Masonry waterproofing paint

– Broom

– Masonry paintbrush



Now, the step-by-step process:


Step 1: Ensure that the wall is clean and dry

Scrape off any peeling paint and sweep down walls to remove dirt or debris. The wall surface must be clean and dry before beginning.


Step 2: Patch Holes

Patch any holes in the wall with expanding hydraulic cement. Allow cement to dry for 24 hours.


Step 3: Paint Wall

Paint the cinder block wall with a thick coat of masonry waterproofing paint, pusing paint into cracks and crevices of block. A paint roller or brush made specifically for masonry is best. All to dry overnight or for a minimum of 12 hours between coats.


Step 4: Add Finish Costs

Cover the wall with a second thick coat and, if needed, a third coat. For the wall to be waterproof, the paint needs to thoroughly cover the cinderblock with none of the block showing through.


How this helps to prevent a water loss:

By patching holes and sealing cracks in your foundation walls, you will prevent any further moisture from entering through the foundation walls. In the long run, you will have helped to prevent water from leaking in through the walls. Cinder blocks are more porous than standard concrete blocks or poured concrete. Only a thin wall (1-1/4 inch) separates the hollow core from wind-driven rain or wet ground, as well as the water-filled core from the indoors.


If you do not seal the cinder blocks now, they can become unsealable after extensive water seepage – after the seeping water has carried clay or soil through the concrete and filled the pores. The telltale sign of this would be brown or “reddish” spots on the interior surface of the wall. Water flows easily through soil but it prevents a penetrating concrete sealer like RadonSeal from penetrating and reacting.


Exterior above-grade cinder block walls are not subject to such a water pressure but wind-driven rain pushes water right into the blocks and eventually, through the wall.


How AmeriClean can help:

AmeriClean handles every water damage project in accordance with Industry Standards regardless of the source of water or the size of the project. In addition to following Industry Standards, our Certified Technicians document the entire loss to prove that the work was done properly. For more information on our Water Damage Restoration and other Water Damage Tips, click on our links.