Top 8 Masonry Waterproofing Products for Interior/Exterior
Water is relentless. Left unchecked, it drives efflorescence through brick, pops spalls in concrete, feeds mold in basements, and pushes paint off block walls. The challenge isn’t just stopping moisture—it’s stopping the right kind of moisture from the right direction without trapping vapor. Choose a coating when you needed a breathable repellent, and you risk blistering. Pick a clear sealer for a below‑grade wall under hydrostatic pressure, and you’ll still get damp spots. The cost isn’t only material; it’s callbacks, downtime, and damaged substrates.
This guide cuts through the confusion by comparing eight proven masonry waterproofing options used by pros—ranging from penetrating silane/siloxane repellents to cementitious and latex barrier coatings. For each product, you’ll see the tech type, interior/exterior and grade rating, surface compatibility, standout features, application and recoat details, coverage and finish, plus where to buy. Whether you’re protecting brick veneer, sealing a slab, or waterproofing a basement wall, you’ll find a clear, job‑ready match below.
1. DeFusco Industrial Supply: Pro-grade penetrating masonry and stone sealers (Tenax and more)
When you need breathable protection—not a paint-like film—DeFusco Industrial Supply stocks pro-grade penetrating sealers from trusted brands like Tenax, built for masonry waterproofing projects that demand water repellency without trapping vapor. Pros lean on these for facades, pavers, and stone where a natural look and long-term durability matter.
Type and technology
Penetrating, non-film-forming sealers engineered to repel liquid water while allowing water vapor to escape. Available in professional water-based and solvent-based options to match jobsite preferences, substrate needs, and VOC requirements outlined by local regulations.
Interior/exterior and grade rating
Suitable for both interior and exterior use. Ideal for above-grade masonry waterproofing where wind-driven rain and splash exposure are concerns. Not intended to resist active hydrostatic pressure on below-grade walls; pair with a true waterproofing coating where bulk water pressure exists.
Surface compatibility
These pro-grade sealers are formulated for porous mineral substrates commonly encountered on jobsites:
- Natural stone: granite, marble, limestone, travertine, and more.
- Concrete and masonry: poured concrete, block, brick, mortar, and stucco.
- Pavers and tile: concrete pavers and many absorbent tiles and grout.
Standout features
Built to help pros move faster with fewer callbacks:
- Breathable water repellency: sheds rain while reducing efflorescence risk.
- Natural look options: invisible finish; enhancing choices available where desired.
- Trusted brands: Tenax and other pro lines selected for stone and masonry.
- Pro support + logistics: fast shipping in the U.S. and Canada with free returns.
Application and recoat
Prep clean, dry, and sound surfaces; test a small area for absorption and appearance. Apply per label with low-pressure sprayer, roller, or brush to achieve even saturation; many penetrating sealers perform best with a wet-on-wet approach. Recoat and cure times vary by product and temperature—follow the specific data sheet.
Coverage and finish
Coverage depends on porosity (dense stone vs. open-face block). Expect a natural, matte appearance from most penetrating masonry waterproofing products; select enhancing versions where color enrichment is desired while maintaining vapor permeability.
Where to buy
Order directly from DeFusco Industrial Supply—an e-commerce supplier focused on stone, tile, and masonry pros—with phone and email support, U.S. and Canada shipping, free returns, and a downloadable PDF catalog for easy spec review.
2. DRYLOK Extreme concrete and masonry waterproofer
When moisture is moving through block or poured walls, a high-build barrier beats a simple repellent. DRYLOK Extreme is a purpose-built coating among masonry waterproofing products, designed to create a continuous, protective film on concrete and masonry so damp spots don’t telegraph through finished spaces.
Type and technology
High-build, film-forming waterproofing coating for masonry and concrete. Unlike penetrating repellents, it forms a durable barrier layer to block liquid water intrusion through porous substrates.
Interior/exterior and grade rating
Rated for interior and exterior use and suitable for above- or below-grade applications per the manufacturer. Use it where walls face persistent moisture exposure rather than just wind‑driven rain.
Surface compatibility
Applies to properly prepared, sound masonry:
- Concrete block (CMU) and poured concrete
- Brick and mortar (uncoated, porous)
- Stucco and other mineral substrates
Standout features
Pros choose it when a coating is required rather than a sealer:
- Barrier performance: Built to stop water penetration through porous masonry.
- Versatile placement: Interior/exterior; above/below grade per DRYLOK.
- Proven usability: Customers report a thick, easy-to-apply feel with solid coverage and results when applied correctly.
Application and recoat
Prepare clean, bare masonry; address defects before coating. Apply per label with brush, roller, or appropriate sprayer to drive the first coat into pores; additional coats are typically required for full waterproofing performance. Follow manufacturer dry/recoat windows and curing guidance.
Coverage and finish
Coverage varies widely with porosity (first coat usually absorbs more). Dries to a uniform, opaque, paint-like finish suitable as a finished surface or under subsequent coatings where allowed by the label.
Where to buy
Available directly from the manufacturer and through major home improvement and paint retailers across the U.S. and Canada. Consult local availability and product data sheets before specifying.
3. Sika ThoroSeal Plus concrete and masonry waterproofer
When you want a bonded, cementitious barrier that becomes part of the wall, Sika ThoroSeal Plus delivers. It’s a dry, polymer‑modified, cement-based coating used for sealing and protecting concrete and masonry—ideal when penetrating sealers won’t stop persistent moisture and you prefer a mineral finish over a paint film.
Type and technology
A polymer‑modified, cement-based waterproofing coating. As a cementitious system, it builds a rigid, durable layer that adheres to mineral substrates to help resist water intrusion.
Interior/exterior and grade rating
Engineered for sealing and protecting concrete and masonry in interior and exterior settings. Always confirm suitability for specific exposure (splash, wind-driven rain, or hydrostatic conditions) with the product data.
Surface compatibility
Use on sound, properly prepared, porous mineral surfaces common on structural envelopes:
- Concrete and CMU block
- Brick, mortar, and other masonry substrates
- Stucco and similar cement-based surfaces
Standout features
Cement chemistry that works with masonry, not against it:
- Polymer‑modified bond: Formulated for strong adhesion to mineral substrates.
- Cementitious durability: Rigid, abrasion‑resistant finish for tough environments.
- Purpose‑built waterproofing: Designed specifically to seal concrete and masonry.
- Brand confidence: Backed by Sika’s building‑envelope expertise.
Application and recoat
Prepare clean, sound, uncoated surfaces per label. Mix and apply as directed using a suitable brush, roller, or sprayer, working material into pores. Multiple coats are typically specified; follow Sika’s stated recoat windows and cure times for performance.
Coverage and finish
Coverage varies by substrate porosity and specified thickness. Cures to a uniform, cementitious, opaque finish appropriate for functional waterproofing on mineral surfaces.
Where to buy
Available through Sika’s retail channel and building supply distributors nationwide. Check local availability and the current product data sheet before specifying or installing.
4. PROSOCO silane/siloxane water repellents (Siloxane PD, Saltguard WB)
For façades, pavers, and exposed masonry that need to shed rain and resist de-icing salts without a paint film, PROSOCO’s masonry water repellents are a go-to. Their line is engineered to prolong the life of hard surfaces by repelling water, salt, oil, and stains—standout choices include Siloxane PD and the water‑based Saltguard WB.
Type and technology
Penetrating, non-film-forming water repellents designed for masonry and other hard surfaces. This class of products helps block liquid water and common contaminants while leaving the substrate appearance largely unchanged.
Interior/exterior and grade rating
Best suited to exterior exposure and above-grade masonry where wind‑driven rain and splash/salt are the primary threats. Not intended to counter active hydrostatic pressure—use a dedicated waterproofing coating in those conditions.
Surface compatibility
Formulated for porous, mineral-based surfaces common on building envelopes and hardscape:
- Concrete and CMU
- Brick and mortar
- Natural and cast stone
- Pavers and other absorbent masonry
Standout features
- Repels water, salt, oil, and stains: Helps reduce weathering and contamination.
- Category clarity: Options such as Siloxane PD and Saltguard WB address typical façade and hardscape needs; WB indicates a water‑based choice.
- Service life focus: Built to help extend substrate life by limiting moisture and contaminant ingress.
Application and recoat
Clean, sound, and dry substrates are essential. Apply by low‑pressure sprayer, roller, or brush to achieve even saturation; a wet‑on‑wet method is commonly used with penetrating repellents. Always test a small area and follow the product label for recoat and cure windows.
Coverage and finish
Coverage varies with porosity and finish profile; dense stone uses less, open-face block more. Expect a natural, clear appearance typical of penetrating repellents, helping maintain the substrate’s original look.
Where to buy
Available through PROSOCO’s national distribution network and building supply retailers. Verify local availability and consult the current product data sheet to match the right repellent to your substrate and exposure.
5. Stormdry masonry protection cream (brick, stone, mortar)
For vertical façades that need a clear, natural-look defense against rain, Stormdry Masonry Protection Cream is a practical pick among masonry waterproofing products. Marketed as a transparent waterproof brick sealant, it’s compatible with masonry, brickwork, mortar, and concrete—ideal when you want repellency without a paint film.
Type and technology
Penetrating, cream-formulation waterproofer that soaks into porous mineral substrates rather than forming a surface film. The result is water repellency while keeping the original appearance of the substrate.
Interior/exterior and grade rating
Commonly used on exterior, above-grade masonry to resist wind‑driven rain and splash exposure. Not intended for situations with active hydrostatic pressure; use a dedicated waterproofing coating for below-grade walls or where bulk water is present.
Surface compatibility
Engineered for typical building and hardscape minerals found on envelopes and chimneys:
- Brick and brickwork
- Mortar joints
- Concrete surfaces
- Stone and general masonry
Standout features
- Transparent protection: Helps shed liquid water while maintaining a natural look.
- Cream format for verticals: Controlled application with reduced dripping and run-off.
- Single-product simplicity: Designed specifically for brick, stone, concrete, and mortar.
Application and recoat
Prepare clean, dry, sound substrates; remove contaminants that could block penetration. Apply per label using a brush or roller to achieve uniform coverage; always test a small area first and follow the product’s stated recoat and cure guidance.
Coverage and finish
Coverage varies by porosity (dense brick vs. open mortar or block). Dries clear, preserving the substrate’s natural tone and texture typical of penetrating masonry waterproofers.
Where to buy
Available through major online retailers and building supply outlets in the United States. Confirm local availability and review the current product label to match substrate and exposure conditions before specifying.
6. KILZ Basement & Masonry waterproofer
When a damp basement wall needs a true coating—not just a repellent—KILZ Basement & Masonry Waterproofing Paint is a solid, pro-friendly choice among masonry waterproofing products. It’s purpose-built for porous concrete and masonry where you want a continuous barrier and an even, paint-like finish.
Type and technology
Film-forming waterproofing paint. Unlike penetrating sealers, it creates a protective coating that helps block liquid water from migrating through porous mineral substrates.
Interior/exterior and grade rating
Designed for interior and exterior use, commonly specified on basement walls and other masonry exposed to intermittent moisture. Always verify suitability for below-grade and hydrostatic conditions on the current label.
Surface compatibility
Formulated for porous concrete and masonry:
- Concrete and CMU block
- Brick and mortar
- Stucco and other cement-based substrates
Standout features
- Barrier protection: A coating system to help stop water penetration through porous walls.
- Versatile placement: Interior/exterior flexibility for multiple assemblies.
- Straightforward application: Thick, workable consistency suited to brush/roller work.
Application and recoat
Prep is critical: clean, sound, and properly cured masonry; repair cracks and defects. Drive the first coat into pores with a brush; follow with additional coats per label. Observe manufacturer dry/recoat windows and full cure before exposing to moisture.
Coverage and finish
Coverage varies widely with substrate porosity; the first coat typically absorbs more. Dries to a uniform, opaque, paint-like finish appropriate as a standalone surface where permitted by the label.
Where to buy
Available via KILZ’s retail network and major home improvement retailers throughout the U.S. and Canada. Check local availability and consult the latest product data sheet before specifying.
7. Ghostshield Siloxa-Tek 8500 penetrating sealer (Ultra Concentrate available)
When hardscape and vertical masonry need invisible protection from water and de-icing salts, Ghostshield Siloxa-Tek 8500 is a contractor favorite. Sold in an Ultra Concentrate as well as ready-to-use formats, it’s a water-based, penetrating concrete and masonry sealer that leaves no film yet delivers serious repellency for long-term durability.
Type and technology
A penetrating, non-film-forming, water-based sealer that soaks into concrete and masonry to reduce liquid water and salt absorption. It maintains the substrate’s natural look instead of creating a paint-like layer on the surface.
Interior/exterior and grade rating
Commonly used on exterior, above-grade assemblies exposed to rain, splash, and de-icing salts. Like other penetrating repellents, it isn’t designed to resist active hydrostatic pressure; use a dedicated waterproofing coating for below-grade or water-bearing walls.
Surface compatibility
Formulated for porous mineral substrates encountered on site:
- Concrete and CMU block
- Masonry and mortar joints
- Brick and other absorbent masonry surfaces
Standout features
- Invisible protection: Dries clear with no film to peel or blister.
- Water and salt repellent: Helps reduce absorption from rain and de-icing salts.
- Ultra Concentrate option: Mix on site to cut shipping weight and storage space.
- Water-based convenience: Low odor and straightforward cleanup.
Application and recoat
Prep is key: clean, dry, and sound substrates free of sealers or contaminants. Apply by low-pressure sprayer, roller, or brush for uniform saturation; a wet-on-wet pass is often recommended with penetrating sealers. If using the Ultra Concentrate, dilute exactly per the label. Always test a small area and follow the manufacturer’s recoat and cure windows.
Coverage and finish
Coverage depends heavily on porosity and surface profile. Expect a natural, clear finish that preserves the original color and texture while shedding water; additional passes may be used to reach refusal on very absorbent substrates.
Where to buy
Available through major home improvement retailers and online channels in the U.S., including options listed under concrete and masonry sealers. Check the current product label and data sheet to confirm dilution, application method, and substrate suitability before specifying.
8. DRYLOK Original masonry waterproofer
For damp, porous walls that need a true barrier rather than a breathable repellent, DRYLOK Original is a dependable, latex-based coating among masonry waterproofing products. Pros reach for it when they want a uniform, paint-like finish that helps stop water from telegraphing through concrete, block, and brick.
Type and technology
Latex-based, film-forming waterproofing paint. Unlike penetrating repellents, it builds a continuous coating across masonry pores to help block liquid water migration.
Interior/exterior and grade rating
Designed for interior and exterior use, commonly applied on basements and exterior masonry exposed to the elements. Always verify suitability for below-grade and hydrostatic conditions on the current product label.
Surface compatibility
Formulated for porous mineral substrates encountered on residential and light commercial projects:
- Concrete and CMU block
- Brick and mortar
- Stone and other masonry
Standout features
- Barrier coating: Helps stop water penetration through porous walls.
- Latex convenience: Brush/roller friendly with straightforward cleanup.
- Versatile placement: Interior/exterior flexibility for multiple assemblies.
- Flat aesthetic: Practical, uniform finish on utility and storage spaces.
Application and recoat
Prep clean, sound, uncoated masonry; repair cracks and voids. Drive the first coat into pores with a stiff brush, then follow with additional coats per label. Observe dry/recoat windows and full cure before moisture exposure.
Coverage and finish
Coverage varies with porosity; the first coat typically absorbs more on CMU and rough substrates. Dries to an opaque, flat finish; white is a common stocked color.
Where to buy
Available through major home improvement retailers and paint suppliers across the U.S. and Canada, as well as the manufacturer’s distribution network. Check local availability and the latest data sheet before specifying.
Choose the best fit for your project
Start with the moisture driver, not the brand. If you need a breathable, natural-look finish on above-grade masonry, choose a penetrating repellent. If you’re fighting damp block or active seepage through walls, you need a barrier coating. When you want a mineral bond that becomes part of the wall, a cementitious system makes sense. Match chemistry to substrate porosity, exposure (rain, splash, salts), and the finish your client expects.
- Natural look, above-grade façades: PROSOCO repellents, Ghostshield Siloxa‑Tek 8500, or Stormdry.
- Salt and freeze‑thaw exposure: PROSOCO Saltguard WB or Ghostshield Siloxa‑Tek 8500.
- Persistent damp/below-grade walls: DRYLOK Extreme/Original or KILZ waterproofing paint.
- Cementitious bond and durability: Sika ThoroSeal Plus on sound mineral substrates.
- Stone, pavers, mixed masonry with pro support: DeFusco’s penetrating options (e.g., Tenax).
Still unsure? Talk to a specialist and source everything in one place at DeFusco Industrial Supply for pro-grade selection and job-ready support.
