Light Weight Fill Polyurethanes: Uses and Properties

NCFI Geotechnical’s polyurethane systems are engineered with both performance and practicality in mind. The light-weight fill product line is a dual-component system, specifically designed to meet the demands of a wide range of geotechnical applications. In this article, we’ll explore the key properties and project benefits that make the lightweight fill polyurethane systems a versatile and effective solution for challenging fill and stabilization needs.

NCFI-2.2FX (Formerly Strata-Fill 24-023)

The first and fastest of 3 lightweight fill formulas, this polyurethane offers low exothermic properties, fast reactivity, ideal for applications requiring controlled placement, such as creating pipeline pads and trench breakers or stabilizing accessible voids. In these situations, rapid expansion helps minimize material migration and ensures targeted support. Fast reactivity also means being able to apply this product to vertical surfaces in a spray application, such as sheet piles or exposed earth voids encountered during excavation. Like any of our polyurethane formulas, NCFI-2.2FX has been tested to ASTM standards- measuring its free rise density at 2.0 – 2.2 PCF and compressive strength at 44 PSI. Highly resistant to chemical exposure, mold or mildew growth, this formula is ideal for the following applications:

• Pipeline Pads / Pillows
• Trench Breakers
• Low-Exotherm Void Filling
• Rock Shields

To learn more technical details about NCFI-2.2FX, check out the TDS sheet.

NCFI-2.2SHX (Formerly Strata-Fill 24-039)

Similar to the other formulas in this product line, NCFI-2.2SHX is also low exotherm. This formula, however, is unique from the others. It is slow reacting and offers hydrophobic / hydro-insensitive properties. This formulation can also be produced to meet NSF/ANSI/CAN 61 requirements upon request, making it suitable for use in applications involving potable water. Per ASTM testing standards, this formula has a free rise density of 2.2 PCF and a compressive strength of 35 PSI. This formula performs well in wet environments, resisting mold, mildew, and solvents. Use 24-039 for these applications:

• Filling Large Voids
• Pipe Abandonment
• Underground Tank Abandonment
• Soil Stabilization

To learn more about NCFI-2.2SHX, read our TDS sheet. 

NCFI-2.2SX (Formerly Strata-Fill 24-070)

The third and final formula in the lightweight fill product line, NCFI-2.2SX has low exothermic properties, slow reactivity, and excellent flow. Excellent flow characteristics are critical for projects where material must navigate tight spaces, irregular voids, or complex areas—ensuring uniform fill, complete coverage, and consistent performance throughout the treated area. According to ASTM testing, this polyurethane has a free rise density of 2.2 PCF and a compressive strength of 30.9 PSI. Its excellent chemical resistance prevents damage from solvents, mold, and mildew. NCFI-2.2SX works well for the following applications:

• Filling Large Voids
• Pipe Abandonment
• Underground Tank Abandonment

To learn more about this formula, read our TDS sheet. 

When it comes to dual component polyurethanes, NCFI's lightweight fill products are an excellent solution for projects that require large void or cavity fill applications where a large amount of material may be used without overheating or scorching. They provide an excellent opportunity for accomplishing unique projects with innovative materials.
Thinking about a lightweight system for your next project? Contact NCFI Geotechnical today and our Technical Support team can help you choose the best system to meet your project's needs.