LABPOX 35 | 100% Solids Epoxy for Porous Concrete and Pinhole Control

LABPOX 35 is a professional grade, 100% solids, 2 to 1 epoxy system engineered specifically for porous concrete and challenging substrates. Where standard epoxies might struggle with pinholes and outgassing, LABPOX 35 is designed to seal the slab and provide a consistent foundation for your decorative or protective system.

This product is the industry preferred choice for use as a base coat or receiver coat on inconsistent slabs. Whether you are installing a high end metallic floor or a heavy duty flake system, LABPOX 35 solves surface problems before they can affect your final finish quality.

If you are dealing with porous concrete, pinholes, or "thirsty" slabs, this is the highest-performing epoxy solution in the One Stop lineup.

Surface Preparation Requirements

Proper surface preparation is critical to the performance of LABPOX 35. Failure to prepare the substrate correctly will result in poor adhesion and surface defects.

• Mechanical Preparation: Surface must be mechanically prepared (grinding or shot-blasting) to a minimum CSP-2 profile. All pores must be open to allow proper penetration.
• Clean Surface: Concrete must be clean, dry, and free of grease, oil, paint, or curing agents.
• Concrete Cure Time: New concrete must cure for a minimum of 28 days.
• Moisture Testing: Moisture content must be below 4%. Test multiple areas of the slab before application.
• Fiber Reinforced Concrete: All exposed fibers must be completely removed (burnt or ground) prior to coating to prevent voids.
• Repair: Significant voids or cracks should be addressed prior to coating to ensure a seamless finish.

Mixing Instructions

Proper mixing is critical to the performance of LABPOX 35, especially when working with porous concrete.

• Pre Mix Part A: Mechanically mix Part A in its original container for at least 1 minute to ensure all solids and pigments are fully suspended.
• Mix Ratio: Combine 2 parts Part A with 1 part Part B in a clean mixing container.
• Mix Time: Mix for a minimum of 3 minutes using a low speed drill and a Box mixer at 300 to 450 RPM.
• Technique: Scrape the sides and bottom of the container to ensure a completely uniform mixture.
• Immediate Placement: Once mixed, the material must be immediately poured onto the floor in ribbons. Leaving material in the bucket will cause it to heat up (exotherm) and drastically reduce working time.

Application

To ensure equal down pressure and a uniform profile, apply using an 24-inch 3/16th inch notched squeegee and an 18" X 3/8" nap roller. Use a 9-inch roller only for detail edge work. This technique ensures the material can properly lay down and seal the slab.

Recoat and Sanding Requirements

Timing is critical to ensuring a chemical bond between layers. Follow these guidelines for a professional finish:

• Within 24 Hours: A second coat may be applied without the need for sanding.
• After 24 Hours: The surface must be mechanically sanded to achieve a uniform dull finish. All gloss must be removed to ensure a proper mechanical bond.
• Cleaning: After sanding, vacuum all dust and wipe the surface with denatured alcohol. The surface must be completely clean and dry before applying the next coat.

Coverage Rates

*This is a very heavy duty high strength commercial grade epoxy that is applied thick. Coverage will vary depending on the porosity and mechanical profile (CSP) of the concrete.

Frequently Asked Questions

When should I use LABPOX 35 instead of LABPOX 30?
Use LABPOX 35 when working with porous concrete or when pinholes are a concern. It is formulated to bridge those gaps. LABPOX 30 is typically used for smoother surfaces or as a build coat.

Do I really have to sand after 24 hours?
Yes. After 24 hours, the epoxy cures to a hard, glossy finish that new layers cannot "stick" to chemically. Sanding creates a mechanical "tooth" that allows the next layer to bond securely.

Can I use this as a standalone coating?
Absolutely. LABPOX 35 is a high performance 100% solids epoxy that can be used as a standalone system in industrial or commercial environments where UV stability isn't the primary concern.

Does this help prevent pinholes?
Yes. This product is specifically formulated to reduce pinholes caused by air release in porous concrete, provided the slab has been properly prepared to a CSP-2 profile.

What happens if I leave the mixed material in the bucket?
Because this is a 100% solids system, it generates heat (exotherm). If left in the bucket, it will cure rapidly often in minutes and can become hot enough to melt the plastic or smoke. Always pour in ribbons immediately.

Can I apply this over a previous coating?
Only if the previous coating is well bonded and has been mechanically sanded to a completely dull finish. We always recommend testing a small area for compatibility first.

Why is 28 days required for new concrete?
New concrete holds a high amount of moisture. Coating too early traps that moisture, which leads to hydrostatic pressure that can blow the epoxy right off the slab.

Is an 18-inch roller mandatory?
While not "mandatory," it is the professional standard. An 18-inch roller provides more uniform down pressure, which is essential for forcing the epoxy into the pores of the concrete to stop outgassing.