Why Garage Floors Sink in Katy TX — Causes & Solutions

Cause 1: Soil Consolidation Under Load

When a garage floor slab is poured, the weight of the concrete compresses the soil beneath. If the soil wasn't properly compacted during construction, or if fill soil was used (common in newer Katy subdivisions), consolidation continues for years after the pour. The slab slowly sinks as voids compact. This produces gradual, uniform settlement — the floor dips slightly across its full area.

Cause 2: Clay Shrinkage Voids

Katy TX clay soil shrinks dramatically during drought. Extended dry periods in 2011, 2022, and 2023 caused significant clay shrinkage beneath Houston-area foundations. When clay shrinks away from the underside of the slab, it creates a void. The slab may span that void initially, then crack and drop when the void becomes large enough. The classic sign: a section drops suddenly after a dry period, often along a control joint.

Cause 3: Plumbing and Drainage Erosion

Leaking underground plumbing beneath a garage slab can erode soil, creating progressive voids that eventually cause settlement or sinkholes. Signs: localized settlement directly above known pipe runs, wet areas on the slab surface with no roof source, or new settlement after plumbing repairs. This requires a plumbing investigation before any remediation — lifting a slab over an active leak is pointless.

What We Can Do

For settled floors, our role is: (1) assess severity and likely cause; (2) refer to a slabjacking contractor if structural lift is needed; (3) coordinate the sequence so epoxy is installed after stabilization; (4) level minor variations (up to 1") with SLU or grinding; (5) install the final epoxy system. We don't do slabjacking ourselves, but we work with trusted local contractors and manage the handoff. The goal is to hand you a flat, stable, beautifully coated floor.