How to Remove Stone Impregnating Sealers and Color Enhancers

Frederick M Hueston StoneForensics.com

Removing impregnating sealers and color enhancers from stone surfaces can be a challenging task, especially since these products are designed to penetrate the stone and provide long-lasting protection. Whether you are correcting an application mistake, addressing discoloration, or preparing the surface for refinishing, following the correct procedures is crucial. This guide provides detailed steps and recommended chemicals for effective removal.

Step 1: Identify the Type of Sealer or Enhancer

Before starting, determine the type of sealer or color enhancer that was applied. Common types include:

• Solvent-based impregnators: These are typically harder to remove due to deeper penetration.
• Water-based impregnators: Easier to remove but still require specific chemicals.
• Color enhancers: Usually solvent-based and designed to darken or enrich the stone’s color.

Understanding the product type helps in choosing the appropriate removal method and chemical.

Step 2: Gather Necessary Supplies

You will need:

1. Protective gear: Gloves, goggles, and a respirator if using strong solvents.
2. Scrub brushes: Nylon or natural bristle brushes for agitation.
3. Chemical strippers: Choose based on the type of sealer or enhancer (details below).
4. Plastic sheets: For dwell time.
5. Pressure washer: Optional, for outdoor stone surfaces.
6. Absorbent materials: Rags or poultice materials for deeper impregnation.

Step 3: Choose the Right Chemical Stripper

The chemical selection is critical for effective removal. Below are recommended chemicals for different sealer types:

1. For Solvent-Based Sealers and Enhancers:
   • Methylene Chloride-Based Strippers: Highly effective for deep-penetrating sealers.
     • Recommended product: Klean-Strip Premium Stripper.
     • There are also Non Methylene Chloride strippers that may also work and are safer to use. These are usually called safe strippers.
   • Acetone or Xylene: For lighter solvent-based sealers.
     • Recommended product: Sunnyside Xylene.

2. For Water-Based Sealers:
   • Alkaline Strippers: These break down water-based formulations.
     • Recommended product: Aqua Mix Sealer & Coating Remover.
   • Detergent-Based Strippers: For less aggressive removal.
     • Recommended product: Prosoco’s Sure Klean Stripper.

3. For Heavy Color Enhancers:
   • Solvent Gel-Based Strippers: These cling to vertical surfaces and allow extended dwell times.
     • Recommended product: StoneTech Heavy Duty Coating Stripper.

Step 4: Application Process

1. Surface Preparation:
   • Clean the stone thoroughly to remove dirt, oils, or surface debris.
   • Test the stripper in an inconspicuous area to confirm compatibility and effectiveness.
2. Apply the Stripper:
   • Generously apply the chemical stripper using a brush or roller.
   • Work in manageable sections to maintain control over the process.
3. Dwell Time:
   • Cover the applied stripper with plastic sheeting to prevent evaporation and allow it to penetrate deeply.
   • Allow the stripper to dwell for the recommended time (usually 20–40 minutes for most products).
4. Agitate the Surface:
   • Use a nylon or natural bristle brush to agitate the surface, loosening the sealer or enhancer.
5. Rinse the Surface:
   • Use clean water or a pressure washer to rinse away the stripper and dissolved sealer.
   • For indoor surfaces, use a wet vacuum to collect residues.

Step 5: Repeat as Necessary

For stubborn impregnating sealers or multiple layers of color enhancers, repeat the application and removal process. Allow the surface to dry between applications to assess progress.

Step 6: Perform Final Cleaning

After removal, clean the surface thoroughly with a pH-neutral stone cleaner to neutralize any remaining chemicals and restore the stone’s natural state.
Recommended product: MB-5 Stone & Tile Cleaner.

Step 7: Evaluate the Surface

Once the sealer or enhancer is removed, evaluate the stone for any staining or discoloration. If necessary, proceed with a poultice or stain removal process before reapplying a new sealer.

Important Tips and Warnings

1. Ventilation: Ensure proper ventilation when working indoors, especially with solvent-based strippers.
2. Test First: Always test in a small area to avoid damaging the stone.
3. Use Caution with Acids: Avoid acidic products, as they can damage certain stone types like marble and limestone.
4. Follow Manufacturer Instructions: Adhere to the instructions provided with your chosen chemical stripper.

Removing impregnating sealers and color enhancers requires patience and the right tools, but with the steps outlined above, you can restore the stone to its original state. Always prioritize safety and proper technique to protect both the stone and yourself.