ARDEX K 301 Exterior Self-Leveling Concrete Topping – 50 lb Gray Bag, Fast-Drying Cement Underlayment for Interior & Exterior Floors, Freeze-Thaw Resistant, High-Strength Concrete Resurfacer (12435)

Product Features:

• Self-Leveling Resurfacer: Self-leveling topping and underlayment designed for fast-track resurfacing and smoothing of both exterior and interior concrete surfaces, delivering a flat, even finish with minimal effort
• High-Strength Cement Blend: Formulated with a premium blend of Portland cement and advanced hydraulic cements to provide exceptional early strength, long-term durability, and reliable performance in demanding conditions
• Flexible Installation Depth: Installs from 1/4" to 3/4" neat and up to 2" with aggregate, eliminating the need for metal lath while allowing versatility for both shallow repairs and deeper resurfacing applications
• Rapid Drying Performance: Walkable in just 2–3 hours and ready for water-based coatings in as little as 24 hours, helping to reduce project downtime and support fast-track construction schedules
• Freeze-Thaw Resistant: Engineered to withstand harsh environmental conditions, including freeze-thaw cycles, making it ideal for outdoor use in wet areas such as balconies, driveways, terraces, and light-industrial floors
• Multi-Surface Compatibility: Effectively levels and smooths a variety of substrates including concrete, terrazzo, existing epoxy coatings, ceramic tile, quarry tile, and other approved non-porous surfaces
• Moisture Control Compatible: Fully compatible with ARDEX MC™ Moisture Control Systems and suitable for use with a wide range of commercial and residential floor coverings, ensuring reliable installation performance
• Eco-Friendly Formula: Zero-VOC formulation supports environmentally responsible building practices, contributes to LEED® credits, and promotes healthier indoor air quality
• Versatile Project Use: Ideal for commercial, residential, and light-industrial applications on, above, or below grade, offering a dependable solution for concrete repair, leveling, and preparation

Product Description:

ARDEX K 301™ Exterior Self-Leveling Concrete Topping is a professional-grade, cement-based resurfacing compound engineered to restore, smooth, and level worn or uneven concrete surfaces in both interior and exterior environments. Designed for contractors and flooring professionals, this high-performance underlayment provides a reliable solution for creating flat, durable substrates that meet the demands of modern construction and renovation projects.

Utilizing advanced rapid-hardening technology, ARDEX K 301 significantly reduces downtime by allowing foot traffic in as little as 2 to 3 hours and enabling the application of water-based coatings within 24 hours. This makes it an excellent choice for fast-track projects where time efficiency is critical. The product is formulated with a specialized blend of Portland cement and hydraulic cements, delivering superior bond strength and long-lasting durability. Its freeze-thaw resistance ensures consistent performance in exterior applications and harsh climates, while its ability to be installed at varying thicknesses—from 1/4 inch up to 2 inches with aggregate—provides exceptional flexibility across a wide range of resurfacing needs.

ARDEX K 301 can be used as a finished wearing surface or as an underlayment beneath tile, luxury vinyl tile (LVT), carpet, epoxy coatings, and other flooring systems. It is compatible with properly prepared concrete and a variety of non-porous substrates, including terrazzo, ceramic tile, and existing epoxy coatings, making it highly versatile for renovation and new construction projects alike. Each 50 lb (22.7 kg) bag mixes easily with approximately 5 quarts (4.73 L) of water, producing a smooth, pourable consistency that self-levels for effortless application. The product provides coverage of approximately 23 square feet at 1/4-inch thickness or 12.5 square feet at 1/2-inch thickness. With a compressive strength of up to 4,300 psi after 28 days (ASTM C109), ARDEX K 301 ensures a strong, stable, and long-lasting surface. Whether used in commercial, residential, or light-industrial settings, ARDEX K 301 delivers the performance, efficiency, and reliability professionals need for high-quality concrete resurfacing and floor preparation.

Installation:

Mixing Ratio: 5 quarts (4.73 L) of water per 50 lb. (22.7 kg) bag
Coverage: 23 sq. ft. per bag at 1/4” (2.1 sq. m at 6 mm)
12.5 sq. ft. per bag at 1/2” (1.1 sq. m at 12 mm)