Natural Stone Treatment VOC Water Repellent - Bulk

Natural Stone Treatment VOC — Deep-Penetrating Water Repellent for Limestone, Marble & Calcareous Masonry

Natural Stone Treatment VOC is a modified siloxane water repellent engineered specifically for limestone, marble, and other calcareous masonry surfaces, as well as general masonry types. It is designed for contractors and trades professionals who require long-lasting water repellent protection on both interior and exterior applications. The product penetrates deeply into the substrate to resist water infiltration, acid rain damage, and biological staining from mold, mildew, and fungal growth — without altering the natural appearance of the treated surface.

Unlike conventional silane or siloxane water repellents, Natural Stone Treatment VOC is uniquely modified for effectiveness on calcareous surfaces that standard siloxane chemistries often fail to protect adequately. It also outperforms common acrylic and metallic stearate water repellents in protection quality, while remaining compliant with EPA AIM VOC regulations and suitable for sale in most states and districts with more restrictive AIM VOC requirements.

Technical Specifications

Key Features & Benefits

Deep Penetration for Lasting Protection

The small molecular size of Natural Stone Treatment VOC allows it to penetrate deeply into masonry substrates rather than sitting on the surface. This deep penetration delivers more durable, longer-lasting water repellency compared to surface-film-forming products that can peel, flake, or wear away over time.

Breathable — Does Not Trap Moisture

Treated surfaces continue to breathe after application, allowing moisture vapor to escape from within the substrate. This is critical for contractors working on occupied buildings or structures with existing moisture content, where trapping moisture behind a sealant can lead to spalling, efflorescence, or freeze-thaw damage.

No Surface Film or Gloss

Natural Stone Treatment VOC does not form a surface film or alter the natural appearance of the masonry. This makes it ideal for historic restoration, architectural stone, and any application where preserving the original look of the substrate is a project requirement.

Alkali-Resistant — Protects Mortar & Grout

The formulation is alkali resistant, allowing it to be safely applied over new or existing mortar and grout joints without degrading or losing effectiveness. Contractors can treat entire wall assemblies — stone and joints together — without needing to mask or protect mortar lines.

Reduces Atmospheric Soiling and Biological Staining

The product reduces the severity of biological staining common in regions with high relative humidity, and helps treated surfaces resist dark staining from fungal growth, mold, mildew, and general atmospheric soiling. This reduces the frequency and cost of cleaning and maintenance over time.

VOC Compliant for Multi-State Use

Natural Stone Treatment VOC meets EPA AIM VOC regulations and is suitable for sale in most states and districts with more restrictive AIM VOC rules. This gives contractors working across multiple jurisdictions confidence that the product can be used on most job sites without regulatory concern (excluding California).

Resists Saltwater Pool Environments

The formulation is specifically noted to resist damage from saltwater pools, making it a viable choice for pool surrounds, copings, and adjacent masonry exposed to salt-laden splash and spray.

Common Applications

Limestone and Marble Facades

Formulated specifically for calcareous stone, this product is the preferred choice for treating building exteriors clad in limestone or marble where conventional siloxane repellents are ineffective.

Historic and Architectural Masonry Restoration

The no-film, no-gloss formulation preserves the natural appearance of historic stone, making it appropriate for restoration projects where altering substrate aesthetics is not acceptable.

Mortar and Grout Joint Protection

Alkali resistance allows the product to be applied across full wall assemblies including new or existing mortar and grout joints, protecting them from water infiltration and degradation without adverse chemical reactions.

High-Humidity Environments Prone to Biological Growth

In climates or regions with high relative humidity, Natural Stone Treatment VOC reduces the severity of mold, mildew, and fungal staining on masonry surfaces, lowering long-term maintenance requirements.

Saltwater Pool Surrounds and Copings

The product's resistance to saltwater pool damage makes it suitable for masonry surfaces in close proximity to saltwater pools, including deck pavers, coping stones, and adjacent walls.

Interior Masonry Surfaces

Suitable for interior applications, the product can protect exposed masonry walls, floors, and architectural stone elements inside commercial or institutional buildings.

Compatible Materials

• Limestone
• Marble
• Calcareous masonry surfaces
• Other traditional masonry types
• New and existing mortar joints
• New and existing grout joints

Limitations

• May damage glass or be difficult to remove — always protect glass surfaces prior to application
• Not appropriate for asphaltic or painted surfaces
• Not suitable for synthetic resin paints, gypsum, plaster, or other non-masonry surfaces
• Not recommended for below-grade application
• Will not prevent water penetration through structural cracks, open joints, or material defects
• Not available for use in California due to VOC restrictions
• PROSOCO Strippable Masking is not appropriate for use with this product

Product Documents

• Product Data Sheet
• Product Data Sheet (Canadian French)
• Safety Data Sheet
• Safety Data Sheet (Spanish)
• SDS Canadian French
• VOC Compliance

Application Instructions

Surface Preparation

1. Protect people, vehicles, property, plants, windows, painted surfaces, anodized aluminum, and all non-masonry surfaces from product, splash, spray, residue, fumes, and wind drift.
2. Protect and/or divert pedestrian and auto traffic in the work area.
3. Test metal finishes and glass prior to application — some finishes may be damaged by exposure.
4. Ensure the surface is clean and free of dirt, dust, oils, and other contaminants. Use an appropriate PROSOCO surface preparation cleaner if necessary.
5. Surface must be thoroughly dry before application.
6. All caulks and sealants must be in place and thoroughly cured prior to application.
7. Cap and make watertight the tops of walls prior to application.
8. Fill all cracks and voids when applying in interior settings to prevent fume infiltration into the building.

Environmental and Safety Conditions

1. Ensure fresh air entry and cross ventilation during application and drying.
2. Extinguish all flames, pilot lights, and other potential ignition sources during use and until all vapors are gone.
3. When applying to exteriors of occupied buildings, cover all windows, exterior intakes, and air conditioning vents, and shut down air handling equipment during application and until vapors have dissipated.
4. Best air and masonry surface temperatures for application are between 40–90°F (4–35°C). Allow frozen masonry to thaw before application.
5. On warm days, apply early in the day and to shaded areas. Avoid application on windy days, as rapid solvent evaporation may occur.

Application

1. Apply using a high-volume, low-pressure spray (<50 psi). Sprayers must be fitted with solvent-resistant hoses and gaskets.
2. Note: If the substrate incorporates asphaltic or other crack-suppression membranes, this deeply penetrative treatment may penetrate through exposed stone, tile, grout, or paver surfaces and react with the membrane to cause staining. Always pretest to ensure desired results.

Safety Data Summary

Hazard Information

• Highly flammable liquid and vapor (Flammable Liquids Category 2)
• May cause mild skin irritation
• May be harmful in contact with skin
• Solvent characteristic odor
• Flash point: 61°F (16°C)
• UN Number: UN1866

Personal Protective Equipment

• Wear protective gloves
• Wear protective clothing
• Wear eye protection
• Wear face protection
• Use appropriate safety equipment during application and handling

Safe Handling

• Keep away from heat, sparks, open flames, and hot surfaces — no smoking
• Keep container tightly closed
• Ground and bond container and receiving equipment
• Use explosion-proof electrical, ventilating, and lighting equipment
• Use only non-sparking tools
• Take precautionary measures against static discharge
• Store in a well-ventilated place and keep cool
• Dispose of contents and container to an approved waste disposal plant
• 24-Hour Emergency Information: INFOTRAC at 800-535-5053

Frequently Asked Questions

Q: Can Natural Stone Treatment VOC be used on standard masonry surfaces, or only calcareous stone?
A: It is effective on limestone, marble, and other calcareous surfaces, as well as other traditional masonry types. It is not suitable for asphaltic or painted surfaces, synthetic resin paints, gypsum, or plaster.

Q: Will this product change the appearance or sheen of the treated stone?
A: No. Natural Stone Treatment VOC will not form a surface film or gloss, and is formulated to leave the natural appearance of the substrate unaltered.

Q: Is the product available for use in California?
A: No. Natural Stone Treatment VOC is not available for use in California due to that state's VOC restrictions. It is suitable for sale in most other states and districts with more restrictive AIM VOC regulations.

Q: Can this product be applied over new mortar and grout joints?
A: Yes. The formulation is alkali resistant, making it safe for application over new or existing mortar and grout joints without loss of effectiveness or adverse chemical reaction.

Q: Will it stop water coming through structural cracks or open joints?
A: No. Natural Stone Treatment VOC resists water penetration through existing shrinkage cracks of 0.02 inches or less, but will not prevent water penetration through structural cracks, defects, open joints, or material defects. Those conditions must be addressed before application.

Q: Is this product suitable for below-grade applications?
A: No. Natural Stone Treatment VOC is not recommended for below-grade application.