Best Sealer for Brick

Water Repelling off Brick

The best sealer for brick is a Silane-Siloxane water repellent sealer. Silane-Siloxane water repellent sealers penetrate into the surface of the brick where it chemically reacts to form a water repellent barrier within the pores that causes water and other liquids to bead off the brick. Brick sealed with a Silane-Siloxane water repellent sealer will be more resistant to staining, damage, and deterioration caused by water absorption, snow and ice, mold and mildew, and efflorescence. Silane-Siloxane sealers can be applied to brick walkways and driveways, brick walls, brick buildings, and other brick surfaces.

Silane-Siloxane sealers are breathable sealers that won’t change the look or color of the brick. They will work entirely below the surface, and won’t leave behind a visible surface film or coating.

A second type of water repellent sealer is a Siliconate water repellent sealer, but those types of water repellent sealers aren’t the best type of sealer to use on brick. When siliconate water repellent sealers are applied to dark concrete or masonry, like brick, white crystals can form on the surface. While these crystals can be removed over time, they are semi-permanent which is why siliconate water repellent sealers should not be applied to brick.

Silicate sealers and acrylic sealers are also breathable sealers, but like with siliconate sealers, have issues when applied to red clay brick. Silicate sealers can leave behind a permanent white crystalline barrier on the surface if over applied, and acrylic sealers will delaminate and peel if moisture is present on, in, or below the brick. If you want to use a silicate sealer or an acrylic sealer on brick, it is important to first talk to the manufacturer, and then apply the sealer to a test area to verify compatibility and adhesion.

Silane-Siloxane water repellent sealers are available in both water and solvent based solutions. One isn’t necessarily better than the other. But will provide equal protection on brick. Learn more about Silane-Siloxane sealers.

How to Apply a Brick Sealer

Silane-Siloxane water repellent sealers are very easy to apply to brick surfaces.

  1. Make sure the brick is clean and dry. If the brick was pressure washed, or if it recently rained, make sure the brick has been given at least 24 hours to dry completely.
  2. Using a roller or pump sprayer, apply the first coat of the water repellent sealer. If a water based water repellent sealer was used, the second coat must be applied while the first coat is still wet. If a solvent based water repellent sealer was used, the second coat can be applied in 2-24 hours. Two coats should always be applied because brick is very porous and the first coat will get soaked up into the brick. A second coat will help to ensure consistent coverage and protection.
  3. Keep the brick dry for at least 24-36 hours after applying the sealer. Water repellent sealers can take up to 72 hours to react. If the brick gets wet before the water repellent has had a chance to cure, the sealer could be compromised and the brick could be discolored.