Flowable Fill

Ready mixed flowable fill is commonly referred to as controlled low strength material (CLSM).


Ready mixed flowable fill is usually a blend of cement, fly ash, sand, and water. It is typically designed as a low strength, flowable material requiring no subsequent vibration or tamping to achieve 100% consolidation.

In addition to flowable fill, CLSM is commonly referred to by a wide variety of other names, including controlled density fill, unshrinkable fill, flowcrete, liquid dirt, fly ash slurry, flowable mortar, plastic soil cement, and many other trademark names.


No matter what you call it, flowable fill is the backfill material that out performs any comparative backfill material. Here's why...


Self Compacting & Self Leveling
Unlike traditional granular fill, flowable fill can be placed without the assistance of backhoes, loaders, compacting equipment such as rollers and compactors, as well as the additional operating personnel.


Flowable fill's versatility offers numerous advantages in design and difficult placement conditions. Flowable fill mixtures can be designed to meet a wide variety of project specific performance conditions including strength, set time, unit weight, excavatability, flowability, and thermal properties.


Readily Available
Utilizing byproducts such as fly ash from power plants that burn coal to generate electricity, local ready mixed concrete producers can manufacture and transport flowable fill meeting project specifications.


Common Applications:


  • Sewer trenches

  • Utility trenches

  • Building excavations

  • Bridge abutments

  • Conduit trenches

Structural Fill

  • Road base

  • Mudjacking

  • Subfooting

  • Floor slab base

  • Pipebedding

Other Uses

  • Underground storage tanks

  • Slope stabilization

  • Soil erosion control

  • Mud mats

  • Abandoned sewers

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