How To Seal Concrete Block Walls Inside?

Before sealing concrete walls, it is essential to clean and prepare the surface. This includes applying a moisture barrier, using a penetrating sealer, using a concrete stain, using a concrete paint, applying a decorative concrete overlay, using epoxy coating, or using polyurethane sealant.

Interior sealants are also crucial for waterproofing, strengthening, and preserving the overall appearance of concrete block foundation walls. To seal the blocks permanently against moisture, water vapor, and efflorescence, use a combination of RadonSeal Plus and Ion-Bond Armor Elastomeric Concrete Sealer.

CMUs (Concrete Masonry Units) are used to seal below-grade concrete blocks from moisture and avoid issues with a too-close-for-comfort water table. Hydraulic cement is most useful for filling large cracks and gaps in basement floors and walls, while silicate-based concrete sealers create a chemical seal. For below-grade concrete blocks, a cold fluid-applied asphaltic rubber membrane is the best option.

To waterproof concrete blocks, follow these tips: apply a coating directly on thebare wall, use a breathable/permeable barrier, use a weather-resistant elastomeric layer, repair cracks and fill voids first, install an air and moisture barrier, and use crystalline waterproofing.

In the Midwest with basements, DRYLOK type products are often used to seal moisure wicking through pour concrete or block walls. Thoroseal is used to seal and hide mortar joints and brush for texture. Floorseal Premium Impregnating Sealer is typically used to seal interior concrete floors and walls where dust proofing is not required.

In summary, proper preparation, application of moisture barriers, and silane/siloxane-based sealers are essential steps for waterproofing concrete walls.

Can you waterproof a block wall from the inside?

The application of waterproof sealant or tar-based product on the inside surface of a concrete block or cinder block wall may temporarily resolve a leaky basement, but it traps water within the foundation wall and prevents moisture evaporation. This entrapment of water within the cinder-block wall will eventually accelerate the deterioration of the blocks, leading to greater repair costs and potentially damaging the structural integrity of sections of the foundation walls.

Surface sealants must be applied on the exterior foundation wall surface for proper waterproofing. There are two professional concrete block basement waterproofing methods available: preventing water entry by excavating and waterproofing the foundation wall, or installing an interior weeping tile/perimeter drainage system to purge entrapped water and waterproof the basement. Both methods significantly decrease the rate of deterioration of the foundation.

Should you seal interior concrete walls?

To waterproof basement walls, apply a high-quality waterproof paint like DRYLOK White Extreme Waterproofer to the interior of the walls. This product comes premixed and is applied like a coat of paint, filling all surface holes and allowing it to dry completely before applying a second coat. A 5-gallon container covers about 500 square feet of wall.

Do not apply sealer over painted walls or efflorescence. If you or a previous owner painted the basement walls, remove the paint before applying sealer, which only adheres well to bare masonry. Effluence, or white deposits on concrete walls subject to constant moisture, should also be removed before applying sealer with muriatic acid.

To keep water away from your basement, remove foundation plantings and flowerbeds that require watering, inspect and repair gutters and downspouts, and grade your yard away from the foundation at a minimum of a 2 percent slope. Consider having an exterior drain tile system installed, which can cost $10, 000 or more and requires excavating soil around the outside of the basement to install a perforated drain at the footing level. A waterproof membrane is often installed on the outside of the basement wall, and a buried sump pump is pumped to the surface.

Additionally, consider installing a drainage channel beneath the floor inside the basement. This drain is similar to the exterior drain tile but located just inside the basement walls. New walls are built on the inside of the drain, preventing residual water from seeping through the old basement walls. This job is typically done by a foundation contractor and costs around $5, 000.

How do you waterproof a concrete wall from the inside?

To waterproof concrete walls from the interior, follow these steps:

1. Prepare the substrate by ensuring it is clean, dry, and free of previous products, foreign matter, and loose or crumbling material.
2. Prime the substrate by applying a coat of PermaFlex® (240 sq ft per gal).
3. Patch the surface with a coat of PermaFlex®, then apply a topcoat of 1 coat.
4. Topcoat the wall with 1 coat of PermaFlex®, covering 240 sq ft per gal.

In summary, waterproofing concrete walls from the interior requires a thorough preparation process, including preparing the substrate, priming the surface, patching, and applying a topcoat.

How do you finish interior concrete block walls?

Concrete block walls are often used in construction, but their appearance can diminish curb appeal and resale value. Covering them can improve outdoor space appeal and prevent cracking, rot, mold, and structural failures due to moisture infiltration. Permeable concrete absorbs water, expanding pores, and damages the concrete. Oil settlement and hydrostatic pressure can lead to hairline cracks and leaks.

To protect the concrete block wall, contractors can use decorative stucco, vinyl siding, artificial stone panels, natural stone, and natural green coverings. Polyguard recommends using a quality sealant like Airlok Flex® VP to maximize moisture resistance.

How do you stop water from seeping through concrete walls?

To prevent water seeping through concrete walls, waterproof the exterior with a waterproof coating or membrane or install a drainage system. Install a sump pump in the basement or foundation to remove excess water and prevent further damage. A sump pump is a device that pumps water out of the area when the water level rises above a certain point. If you’re unsure about how to stop water seeping through concrete walls or if the problem is severe, consider seeking professional assistance from Drainage Contractors or Basement Waterproofing Companies in London Ontario. A qualified contractor can help identify the source of the water and recommend the best course of action to address the issue.

What do you use to seal interior concrete?

Concrete sealers are essential for interior decorative concrete work and are commonly used in film-forming formulations. Acrylics form a thin protective coating on the concrete surface, available in solvent and water-based formulations. Polyurethanes form a high-build protective film, ideal for high-traffic flooring and enhancing the beauty of colored, stamped, or exposed-aggregate concrete countertops. Epoxies, two-compound products mixed before application, work well on high-traffic areas like cement-based overlays and are available in clear or pigmented options.

They protect against yellowing and are usually transparent. Hard Rock Concrete Coatings, a trained and experienced concrete professional, can ensure proper application of sealers and provide a free quote for creating a beautiful and unique concrete surface. Contact them for a professional look.

How to waterproof a block foundation from the interior?

To waterproof a concrete block foundation from the interior, install drain tile around the perimeter of your basement. This system directs water entering through the concrete blocks to a sump pump, rerouting it back outside your home. Alternatively, waterproofing the foundation from the exterior requires excavation of the soil surrounding the foundation, which may involve destroying landscaping and disrupting a driveway or garage. After the excavation, apply a waterproof membrane to the foundation walls and install drain tile.

It is essential to hire a professional for waterproofing a concrete block foundation, as it is a complex and labor-intensive task. A waterproofing contractor will have the necessary training, skills, and access to industrial-grade tools and equipment to complete the job correctly. Unless you have extensive experience handling similar projects, it is advisable to entrust the job to professionals.

How do you waterproof an interior concrete wall?

Concrete blocks are commonly used for foundations and outbuildings due to their uniform size, ease of stacking, and hardness. However, they are more permeable to water and water vapor than poured concrete, making them particularly vulnerable. To protect them from water intrusion, it is essential to use the best block wall waterproofing products. Concrete blocks and cinder blocks are particularly vulnerable due to their larger pores, making them semi-permeable.

The permeability of concrete is 3. 2 perms per inch of thickness, while an 8- to 10-inch-thick poured concrete wall is about 0. 4 to 0. 3 perms. Once moisture intrudes into a block, it makes the pores even larger, reinforcing the cycle of damage to the structure. To waterproof concrete blocks, apply a coating directly on the bare wall, use a breathable/permeable barrier, use a weather-resistant elastomeric layer, repair cracks and fill voids first, and install an air and moisture barrier.

How to seal interior cinder block walls?

Concrete block walls and cinder block water barriers are common types of foundations and walls, with advantages such as uniform size, easier stacking, and hardened walls. However, concrete blocks are more permeable to water and water vapor than poured concrete, making them particularly vulnerable. To protect these materials from water intrusion, it is essential to use the best block wall waterproofing products.

Concrete blocks and cinder blocks are heavier than poured concrete, and their larger pores make them semi-permeable. The permeability of concrete is 3. 2 perms per inch of thickness, while an 8- to 10-inch-thick poured concrete wall is about 0. 4 to 0. 3 perms. Once moisture intrudes into a block, it makes the pores even larger, reinforcing the cycle of damage to the structure.

To apply a coating directly on the bare wall, use a breathable/permeable barrier, weather-resistant elastomeric layer, repair cracks and fill voids first, and install an air and moisture barrier.

Does interior concrete need to be sealed?

Concrete sealers are essential for maintaining and enriching the color of concrete, whether it’s integral, stain, dye, or color hardener. They can add sheen, block dirt, oil, grease, and chemicals, and make the surface easier to clean. They also prevent wear and tear from high foot and auto traffic areas.

To choose the right sealer, consider your state’s requirements on volatile organic compounds (VOCs). Sealers with higher VOC levels may not be legal in your state. Acrylic-resin-based sealers are the most common, cost-effective, and often blended with epoxies, polyurethanes, or silicones to improve performance and water resistance. They come in many forms, with some performing significantly better than others.

A less expensive, lower-performing sealer, such as styrene-acrylic, may yellow and degrade when exposed to sunlight or extreme weather conditions. The best type of sealer is a pure acrylic resin sealer that will last longer without yellowing.

How do I stop water from seeping through concrete blocks?

When waterproofing concrete block foundations, it is crucial to follow eight tips: meticulous preparation, repair cracks and fill gaps, use crystalline waterproofing, install an interior drain system, use vapor barriers and cove diverters, avoid sealing if stuccoing, address the exterior, and seal from the outside. Concrete block walls are solid, easy to lay, and cost-effective, but they also have inherent problems in keeping things watertight. Over time, gaps form due to building settlement and hydrostatic pressure from the surrounding ground, displacing mortar and forming cracks.

Even the best waterproofing systems will require maintenance and repair. Therefore, it is essential to address these issues and ensure the foundations are properly waterproofed to maintain structural stability and peace of mind.