Cinderblock is very porous and surrounded with grout lines which makes it easy for water and moisture to quickly and easily travel from the top of the cinderblock down to the bottom. During a rainstorm, a cinderblock wall can become saturated with water in minutes.
Paints, acrylic coatings and other types of similar products that are designed to coat the surface of the concrete can’t stop water or moisture. If these products are used, moisture and water will cause the paint or coating to delaminate from the wall. Before applying a paint or coating, you should consider waterproofing the cinderblock.
There are a few ways to waterproof cinderblock. First, you want to apply a penetrating waterproofing sealer. This can come in the form of a silicate, silicone, silane, siloxane or combination of a few. When choosing a cinderblock sealer, consider the following:
- Application – The ease of application involved with applying the sealer.
- Warranty – What the sealer guarantees and how long it is guaranteed to perform.
- Cost – Not just upfront cost, but the long term costs associated with using the sealer. If the sealer only lasts 1 year, you need to plan on this expense once a year. If the sealers lasts 10 years, divide the cost by 10 and use that price to compare it to other products.
Below is a list of what we found to be the most cost effective solutions to sealing cinderblock:
- Foundation Armor – What we like about Foundation Armor is they use a waterproofing system that works below the surface. If you want to paint or coat the cinderblock after being sealed, you can. They suggest 2 coats of their Armor S2000 sealer followed by 2 coats of their SX5000 sealer. If sealing exterior cinderblock they suggest 2 coats of SX5000.
- PPG Architectural Coatings – This product is more than just a coating, is a premium interior/exterior, light weight, acrylic latex block filler and surface. It bond to the concrete from within the pores.
- Krylon Block Filler – Like with the PPG Coatings, the Krylon Block Filler is designed to bond to the surface and fill in the blocks.
- KILZ Block Filler – KILZ also offers a block filler designed to bond to the surface and fill in the blocks.