How Do You Waterproof Concrete Blocks?
How Do You Waterproof Concrete Blocks?
Here are some ways to waterproof concrete blocks:
1. Apply a coating directly on the bare wall.
Cinder block sealant serves as the initial layer of defense. The Airlock Flex barrier solutions from Polyguard offer reliable protection against air leakage and moisture infiltration. Weather Guard stands for both WG and WG LT, or Weather Guard Low Temperatures.
Both are simple solutions for sealing a concrete block foundation that is water-based, permeable, above-grade air, weather, and vapor coatings that are put directly on the naked side of a block wall.
2. Use a breathable / Permeable barrier
A hydrophobic barrier that repels moisture and vapor is created both inside the block and on its surface by employing block wall waterproofing materials. In addition, any moisture that is already present in the block needs to be allowed to escape.
It would help if you had a permeable, breathable barrier, like Paywall Blue Barrier Liquid Wrap 2300 from Bodyguard.
3. Use a weather-resistant elastomeric layer
A concrete block can collect water during rainstorms or other general exposure if it is not coated to resist it.
The water vapor is then expelled when it warms up. This increases the internal pressure and increases the risk of condensation. Use the peel-and-stick Paywall
4. Use “The Pink Stuff”
Many of the same materials you would use to seal an ICF block wall or a poured concrete wall, such as “The Pink Stuff,” also known as Paywall Home Stretch Peel ‘N Stick Waterproofing Membrane, can also be used to seal a concrete block foundation.
It is applied on ICF in the video above, but it may also be used to waterproof poured or block walls. The peel-and-stick solution is designed for ICFs since it won’t chew into the EPS foam surrounding ICF blocks.
5. Repair Cracks and Fill Voids First
All gaps or fissures in the block surfaces must be sealed and smoothed up with hydraulic cement or masonry caulk before you begin waterproofing a block wall.
Give cement 24 hours to dry. Prior to applying flashings and air barriers, fill holes and seams using PolyWall Blue Barrier Joint Filler 2200.
6. Install an Air and Moisture Barrier
In order to produce a continuous layer surrounding the building and foundation that restricts air movement—and hence water vapor—into and out of the structure, a CMU block wall frequently needs an air and moisture barrier.
The ideal moisture barrier for sealing concrete block walls allows moisture to pass through rather than become trapped, which might lead to condensation within the building.
7. Don’t Apply Concrete Block Sealer over Painted Walls or Efflorescence
It could be tempting to cover up a troublesome wall with paint. That, though, can figuratively seal your fate. If the interior of your basement walls is painted, it will need to be painted off before it can be waterproofed and sealed.
Before applying sealants, it is also required to remove efflorescence, which are white crystalline deposits that develop on the surface of moist concrete.
8. Install Drain Channels
Install an outside drain board to keep water away from your below-grade walls if the block wall you are waterproofing is new. Because this option requires digging around your basement, it is expensive to adapt if the foundation wall is already in place.
Installing one is an excellent best practice preventative step that costs little in comparison to the implications, especially if it can be done for the new buildings.
9. If You’re Planning to Finish Blocks with Stucco, Don’t Seal First!
A CMU must have some moisture for the stucco to adhere when applied. If you seal first, the substrate’s capacity to form this connection will be hampered, which might lead to stucco that won’t adhere.
10. Choose Products That Have Been Tested Together
Waterproofing frequently includes “systems” of techniques. That’s because goods are designed and tested to combine easily.
Choose one brand that produces all the goods you need for a successful installation rather than employing many manufacturers or products. When used together, the items will function at their best, thanks to testing.
11. Gather Your Tools and Prep.
Gather all the equipment you will need, including a roller, sprayer, buckets, cleaning materials, and any other items the product’s maker may recommend so that you are prepared to work when you begin.
Cleanup should come first. Use a roller with stiff bristles or a 3/4-inch nap if you’re rolling on your concrete block foundation sealer to ensure the substance goes into all the pores. Keep in mind that before sealing, cinder block walls must be dry and clean.
