Flowable Fill (CLSM) in New Braunfels & the San Antonio Area
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Flowable fill — also called controlled low-strength material, or CLSM — is a pourable,
self-leveling blend of cement, sand, and water used as backfill and void fill. Because it flows
into place and levels itself, it needs no tamping or mechanical compaction, which makes it
far faster and more reliable than trying to compact soil in tight or hard-to-reach spaces. It flows into voids you can’t get a compactor into and cures into a stable, load-ready fill.
Express Metered Concrete supplies flowable fill for utility crews, road contractors, and municipalities across New Braunfels, San Antonio, and the surrounding region — and because we mix on site with continual loading, we can keep a large backfill job supplied without hot-load worries.
Why Flowable Fill Beats Compacted Soil
Compacting soil backfill in a narrow trench or around a structure is slow, labor-intensive,
and easy to get wrong — poorly compacted fill settles later and causes pavement failures
and sinkholes. Flowable fill removes that risk. It self-levels into every void, requires no
compaction equipment or labor, and cures to a consistent, predictable strength. It’s
typically engineered as low-strength on purpose, so it stays firm and load-bearing but can
still be dug out later if a utility needs to be accessed. For utility and road work on a
schedule, it’s often faster and more dependable than conventional backfill.
What Flowable Fill Is Used For
- Trench backfill and utility cuts.
- Backfill around prefabricated manholes.
- Pipe and conduit encasement.
- Foundation sub-bases.
- Base material for pavers and pavement cuts.
- Filling voids under existing pavement.
Why Our Volumetric Trucks Excel at Flowable Fill
Flowable fill jobs frequently need a large amount of material, quickly, with continual
loading — and that’s exactly what volumetric trucks do well. Our on-site mixing keeps the
material coming without the hot-load worries of drum delivery, lets us adjust the mix to the
placement, and bills you only for what you actually place. On large backfill volumes, paying
by the yard placed rather than by the truck ordered makes a real difference to the job cost.
Why Choose Express for Flowable Fill
You get fast, continual supply for backfill and void work, a mix tuned to the placement, and
metered billing on high-volume pours — plus calibrated trucks, 24/7 scheduling for utility
and road crews, and a local, ACI-member team that understands spec-driven infrastructure
work.
Frequently Asked Questions
What’s the difference between flowable fill and regular concrete?
Flowable fill (CLSM)
is a low-strength, self-leveling material meant to replace compacted soil backfill, not to
serve as structural concrete. It flows into voids without compaction and is usually designed
to stay excavatable for future utility access, whereas structural concrete is designed for high
strength and permanence.
Do I need to compact flowable fill?
No. It self-levels and requires no tamping or
mechanical compaction, which is one of its biggest advantages in trenches and around
structures.
Can flowable fill be dug out later?
Yes, when it’s mixed as a controlled low-strength
material it stays firm and load-bearing but remains excavatable, so utilities buried in it can
be reached later.
How quickly can you supply a large backfill job?
Because we mix volumetrically on site
with continual loading, we can keep large backfill and void-fill jobs supplied steadily
without the hot-load limits of drum delivery.
Serving the New Braunfels and San Antonio Area
From our yard at 2077 Wald Rd in New Braunfels, we cover the I-35 corridor and the Hill Country: