Concrete Solutions for Low Thermal Resistivity

When designing duct-bank systems, proactive risk management is key to preventing potential outage issues. Lafarge presents Thermaflow, an exclusive concrete mix with varying strengths and superior thermal resistivity levels. This advanced concrete solution is tailored to optimize duct-bank system design, ensuring predictable thermal performance and potential cost savings for your project.

Main Characteristics

  • Exceptional Flowability
  • Self-compacting Properties
  • Utilizes Small Aggregate Size to Fill Voids Efficiently
  • Precise Thermal Resistivity
  • Enhanced Heat Dissipation Capabilities

Why Thermaflow™ Thermal Fill?

  1. Efficiently dissipates heat generated by buried cables providing constant electrical power.
  2. Predictable thermal performance enables contractors to optimize conduit capacity, trench depth, and reduce construction costs. 
  3. Allows for shallower trenches and potentially fewer conduit runs, potentially reducing excavation and materials costs.
  4. Local mixes are pre-tested, ensuring confidence in material performance when and where you need it.

The Challenge

Underground transmission lines require a stable thermal environment. Excessive heat can cause:

  • derating of cable ampacity and hot spots
  • reduction in cable lifespan
  • premature cable failure to conduit

Backfill material selection needs to consider:

  • thermal stability
  • low (and accurate) thermal resistivity
  • self consolidation
  • precise spread, viscosity and flowability
  • local availability

Product Availability

  • British Columbia
  • Alberta
  • Manitoba
  • Saskatchewan
  • Ontario
  • Quebec

To Ensure Power That Never Stops:

icon lafargegreen energy

Think Beyond Concrete

Thermaflow minimizes the depth of burial and cost of backfill and maximizes the number of conduits and size of ducts.

icon lafargegreen factory green

Consult Lafarge's Experts

Our experts combine science, soil analysis, and concrete expertise to provide the perfect solution for your project.

icon-lafargegreen lightning issue

Measure, Don't Assume

The rho value of 90 isn't a magic number. Soil conditions vary from location to location.

Contact Us


  • Data centers
  • Electric utilities
  • Wind farms