If you’re protecting an exterior wall, you want a durable, weather-ready solution that fits your surface and climate. This guide presents five proven products suitable for concrete, brick, stone, and masonry walls. Each option targets different needs—porous masonry protection, elastomeric flexibility, penetrating sealers, and paint-with-primer convenience—so you can choose what best fits your project. The buyer types below help you pick: DIY homeowners seeking simple coatings, contractors needing flexible adaptables, and renters or property managers looking for long-lasting protection with low maintenance.
| Product | Best For | Key Benefit |
|---|---|---|
| KILZ Basement and Masonry Waterproofing Paint | Basements, masonry walls, and below-grade areas | Water barrier with nanotechnology |
| Ames Blue Max Liquid Rubber Waterproofer | Foundations and above/below-grade surfaces | Elastomeric, highly flexible membrane |
| MasonryDefender All Purpose Sealer | Outdoor masonry like brick, stone, and concrete | Penetrating, clear barrier preserves look |
| 9900 Sealant Waterproof | Crack and joint sealing on roofs and walls | High flexibility and heat resistance |
| Mollor Exterior Paint And Primer In One | Exterior walls with paint-ready finish | Waterproofing as part of paint film |
Note: For below-grade walls or active leaks, prepare the surface with appropriate crack fillers before applying any coating.
KILZ Basement And Masonry Waterproofing Paint
KILZ Waterproofing Paint creates a water barrier using nanotechnology. It is versatile for interior and exterior concrete, brick, and masonry walls, making it suitable for basement walls and exterior foundations. The finish resists alkali buildup, contributing to durability in high-moisture areas. Best for homeowners who want a combined waterproofing solution and decorative finish in one coat.
Who it’s best for: DIYers tackling both basement walls and exterior masonry, needing a paintable waterproof layer that also resists moisture and alkali. Better for surfaces with minor cracks after prep work.
Caution: Not recommended for floors or walls with active water leaks; prepare large holes/cracks with hydraulic cement before painting.
Ames Blue Max Liquid Rubber Waterproofer
Ames Blue Max is an elastomeric liquid rubber waterproofer with high elongation (1200%), designed for both above- and below-grade surfaces. It provides a flexible, adhesive membrane that resists cracking as the structure moves. It can double as a primer on roofs and works on concrete, wood, metal, and more. Best for surfaces prone to movement or cracking and for projects needing a robust waterproof membrane.
Who it’s best for: Contractors or homeowners dealing with movement-prone walls, foundations, or roofs that require a flexible coating. Better for large, flat exterior areas where a spray or roller can apply evenly. Avoid this if you need a discrete, thin film finish on highly textured surfaces where adhesion might be uneven.
MasonryDefender All Purpose Sealer
MasonryDefender offers a penetrating penetrating sealer that creates a clear, waterproof barrier for exterior masonry like brick, concrete, and stone. This product emphasizes protecting outdoor surfaces without altering their natural appearance. Its 1-gallon size is designed for covering moderate to large outdoor areas.
Who it’s best for: Property owners who want to preserve the original look of their masonry while adding water resistance. Better for preserving texture and color; avoid if you need a visible coating or opaque finish.
9900 Sealant Waterproof
9900 Sealant Waterproof is a silicon-based sealant designed to permanently seal roof and wall cracks. It offers high flexibility (186% elongation) and strong adhesion across surfaces, making it ideal for joints and seams that experience movement or shifting. Best for targeted crack and joint repairs in exterior walls and roofing edges.
Who it’s best for: Homeowners or pros focusing on crack repair and joint sealing in exterior walls. Choose this if you need a flexible sealant that resists heat and weather. Caution: Not a broad, full-wall coating; use where sealant is needed and complement with other waterproofing products for full coverage.
Mollor Exterior Paint And Primer In One
Mollor Exterior Paint And Primer In One provides exterior white paint with waterproof performance. It combines paint and primer in a water-based, low-odor formula, with good adhesion on textured surfaces. It’s designed to prevent rainwater penetration while delivering a durable, aesthetically pleasing finish. Best for homeowners who want a single solution for appearance and protection.
Who it’s best for: Homeowners prioritizing a straightforward, paint-ready exterior finish with built-in waterproofing. Better for those seeking a uniform look without multiple products. Limitation: As with any paint-only approach, preparation and proper priming of cracked surfaces improve longevity.
Buying Guide: Key Considerations For Exterior Wall Waterproofing
- Surface type: Concrete, brick, stone, or stucco each respond differently to coatings. Penetrating sealers work well on porous surfaces, while elastomeric coatings handle movement better.
- Moisture level: Active leaks require initial crack repair or hydraulic cement before applying sealers or paints.
- Movement and temperature: Areas with frequent temperature shifts benefit from flexible membranes or silicone-based sealants.
- Aesthetic goals: If you want a finished color, paint-with-sealer options reduce steps; for natural masonry, penetrating sealers preserve appearance.
- Maintenance expectations: Elastomeric coatings and paints may require periodic inspection for peeling or cracking and reapplication.
- Application method: Consider whether you’ll apply by roller, brush, or spray, and whether a primer is included or required.
Frequently Asked Questions
- What is the best waterproofing option for brick walls? – Penetrating sealers preserve the brick’s look while blocking moisture; for textured brick, elastomeric coatings add a protective film that tolerates movement.
- Do I need a primer with waterproof paints? – Some products include primer and paint in one, while others require a separate primer for best adhesion on challenging surfaces.
- Can these products seal active leaks? – Most product guides advise fixing active leaks before coating; sealants are not substitutes for leak repair in active situations.
- How long does exterior waterproofing typically last? – Longevity depends on surface, climate, and maintenance; elastomeric coatings generally last several years with periodic inspection.
- Should I choose a clear sealer or painted finish? – Clear sealers preserve appearance while adding moisture protection; painted finishes offer color and extra film protection but may require more maintenance.
- Is breathable protection important? – Yes, breathable products prevent moisture from becoming trapped, which can cause issues like efflorescence or mold behind coatings.