Concrete and masonry sealers, waterproofers, crack sealants and mortar repair for patios, walkways, basements, foundations, block walls and slab joints. This collection covers Okon Seal & Finish and Okon W-2, Seal-Krete Original Waterproofing Primer/Sealer, Zinsser Watertite, Valspar Concrete Bonding Primer, Loctite PL S10 and PL S20, Sikaflex Self-Leveling Sealant, DAP AMP Self-Leveling Concrete Sealant, DAP Concrete Watertight Filler and Sealant, and Sashco Mor-Flexx in five colors.
Match the product to the surface and the job. For flat, light-use concrete, Rust-Oleum's Okon Seal & Finish is a water-based, clear low-gloss sealer (VOC under 50 g/L) for patios, walkways and basements; the maker does not recommend it for driveways or garages. For walls, Okon W-2 is a breathable clear water repellent for porous concrete block, stucco and brick, and Seal-Krete Original is a penetrating waterproofing primer/sealer (VOC under 49 g/L) made mainly for vertical surfaces. Neither stops hydrostatic pressure. For cracks and joints in driveways, sidewalks and garage floors, self-leveling polyurethanes like Loctite PL S20 and Sikaflex Self-Leveling flow into horizontal joints with no tooling, while non-sag Loctite PL S10 stays put on foundations and block walls.
| Job |
Products for it |
Notes (maker) |
| Seal patios, walkways, basement floors |
Okon Seal & Finish, Clear, gallon |
Water-based micro-acrylic; clear low-gloss; no acid etch; about 150 to 300 sq ft per gallon first coat; foot traffic in about 12 hours; not for driveways or garages per maker |
| Water-repel porous block, stucco, brick |
Okon W-2, gallon |
Breathable acrylic silane-siloxane; resists water absorption and efflorescence; does not seal cracks |
| Waterproof vertical concrete and masonry |
Seal-Krete Original, Clear, gallon; Zinsser Watertite, White, gallon |
Seal-Krete needs two coats on bare vertical concrete, about 80 to 300 sq ft per gallon, recoat about 2 hours; Watertite is a mold and mildew proof waterproofer for masonry walls |
| Prime bare concrete for porch and floor paint |
Valspar Concrete Bonding Primer, gallon |
Acrylic, VOC under 100 g/L; etch first; topcoat in 1 hour and within 4 hours; apply at 50 to 90°F |
| Flat cracks and slab joints |
Loctite PL S20, Sikaflex Self-Leveling, DAP AMP Self-Leveling Concrete |
Pourable polyurethanes; PL S20 handles foot and vehicle traffic and needs backer rod over 3/8 in deep; Sikaflex Self-Leveling is ASTM C-920 Class 25 |
| Vertical cracks and wall joints |
Loctite PL S10, DAP Concrete Watertight Filler and Sealant |
PL S10 is non-sag and needs no primer on concrete, brick or stone; backer rod over 1/2 in deep; full cure about 7 days |
| Crumbly mortar and cracked stucco |
Sashco Mor-Flexx, 10.5 oz |
Gun-applied mortar repair that stretches like rubber; not for concrete under 6 months old, submerged areas or high traffic |
Shop related: self-leveling concrete sealant, caulk and sealants, primers and sealers, Okon, Seal-Krete, Loctite, Sika, and the garage floor and concrete guide.
FAQ
What is the best sealer for a garage floor?
The clear sealers here are not garage floor coatings. Rust-Oleum says Okon Seal & Finish is not recommended for driveways or garages, and Seal-Krete Original is made mainly for vertical surfaces, though the maker also lists dustproofing or priming floors. For a garage slab, seal the cracks and joints with Loctite PL S20 or Sikaflex Self-Leveling, which both makers list for garage floors.
How do I seal a cracked driveway or sidewalk?
Clean the crack, add closed-cell backer rod if it is deep, then fill with a self-leveling polyurethane such as Loctite PL S20 or Sikaflex Self-Leveling. Sika says its sealant can go on new concrete 24 hours after cure.
Will these stop water coming through a basement wall?
Not if there is water pressure. Okon W-2 and Seal-Krete Original both state they do not stop hydrostatic pressure, and Seal-Krete is not for below-grade use. They help resist water absorption on above-grade masonry.
Do I need to etch concrete before sealing?
It depends on the product. The Okon Seal & Finish data sheet says acid etching is not required. Valspar says to clean, degrease and etch bare concrete before its Concrete Bonding Primer.
How much sealer do I need?
Plan by the maker's coverage: Okon Seal & Finish about 150 sq ft per gallon on rough broom finish up to 300 on smooth trowel, Seal-Krete Original about 80 to 300 sq ft per gallon depending on porosity, and Valspar Concrete Bonding Primer about 250 sq ft per gallon.
