When Slabs Need Flattening, Ardex Self-Leveling Underlayment Works
Uneven concrete slabs stop finish flooring before it starts. Ardex self-leveling underlayment corrects slab flatness so tile, plank, and polished finishes install without compromise. We're an Ardex-system installer in Pittsburgh, meaning primer, pour, and cure follow Ardex spec exactly. Free written estimate.
Tile, plank, and polished concrete all require a flat substrate. A slab with 1/4-inch variation over 10 feet looks wavy under finish flooring and fails the installer's tolerance check. Ardex self-leveling underlayment (SLU) is the engineered solution: it bonds to the existing slab via Ardex primer, flows to a flat plane, and cures to the tolerance the finish flooring needs.
We install as an Ardex-system contractor, which means every step follows Ardex specification. The primer is Ardex primer (not a generic substitute). The SLU is mixed to Ardex water ratio. The cure schedule is Ardex schedule. This system approach is why the finish flooring contractor can install without complaint. See our full Ardex services if the project also needs repair, waterproofing, or overlay work.
The slab flatness issue is common in Pittsburgh warehouses, retail spaces, and residential basements. We coordinate the SLU pour with the finish-flooring trade so timing and tolerance align. Our warehouse floor coating work often includes SLU as the prep layer, and we apply the same rigor to residential polished concrete projects.
Recent work
Installation sequence
How Ardex SLU Gets Installed in Pittsburgh
Measure and plan the pour
We laser-scan the slab to find high and low spots, calculate the SLU depth needed to hit the finish-flooring tolerance, and confirm the plan with the tile or plank installer before we start.
Prep the slab surface
The concrete is diamond-ground to Ardex profile, dust and contaminants removed, and the surface is ready for primer. This step is critical for the bond.
Apply Ardex primer
The matched Ardex primer is rolled across the prepped slab. This is what bonds the SLU to the existing concrete. Skipping or substituting primer voids the warranty.
Mix, pour, and level SLU
Ardex SLU is mixed to spec water ratio, poured across the floor, and allowed to self-level to a flat plane. The material has a working window; we move quickly to use it within that time.
Cure and handoff
The SLU cures to Ardex schedule. We confirm final flatness against the finish spec and hand the slab to the next trade ready for tile, plank, or polish install.
Timing and coordination
SLU Works Best When Scheduled Early
The best SLU projects are planned into the build schedule, not added as an emergency fix. We coordinate with the finish-flooring contractor (tile, plank, or polish installer) up front, agree on the target flatness, and pour to that target. This way the next trade's install runs without surprises.
If the project also needs Ardex overlay or Ardex repair, we can spec those into the same system. Coordination with adjacent Ardex waterproofing is also common on basement and below-grade work.
Bonded primer, tolerance specs, depth ranges and coordination with finish trades.
Ardex offers SLU products that can feather to extremely thin edges (essentially a few mil) and pour up to substantial depths for major tolerance correction. Product choice depends on the tolerance and project; we spec from the Ardex range.
Yes, critically. The Ardex primer is what bonds the SLU to the existing concrete. Without it, the SLU delaminates over time. Skipping or substituting the primer voids the Ardex system warranty.
Sometimes, with the matched Ardex polishable or top-coated overlay product. Most projects use SLU as substrate for tile, plank, or another finish; using it as the finish itself requires a different product spec.
Foot traffic typically the same day or next; finish-flooring install usually waits longer for the SLU to cure and dry to the finish spec. The cure schedule is in the project handoff.
Cost depends on depth, area, and existing slab condition. We provide a written quote based on the actual project; budget guidance can be discussed during the assessment.
Client reviews
What Pittsburgh Clients Say About Ardex Self-Leveling
They prep with Ardex primer like the spec calls for, not a generic primer. SLU bonds properly, my tile install goes in on a flat substrate. The Ardex-system difference is real.
Z. T5
Tile Contractor, Pittsburgh
★★★★★
Coordinated the SLU pour with my schedule, agreed the target tolerance up front, hit it on the pour. My plank install ran without complaint. Trade coordination at its best.
Y. T5
Finish Floor Installer, Aliquippa
★★★★★
Three different substrate areas with different tolerance issues, three different Ardex SLU products specced. Each one matched the conditions; the finish-flooring went over each cleanly.
Q. T5
GC, Monroeville
★★★★★
Tight feather-edge work at door thresholds where standard SLU would not work. They used the right Ardex product, feather edge held, no telegraph through the finish.
X. T5
Custom Home Builder, Mckeesport
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