When the shell itself is the leak

Most pools in this part of Brazoria County are shot with the same material: gunite, a sprayed concrete mix built over a steel rebar cage, then finished with plaster or pebble. Done right, that shell lasts decades. But it isn't flexible, and the ground it sits on isn't stable. When enough movement happens underneath it, the shell cracks the way any rigid slab cracks when the earth under one section drops while another holds. That's a different repair than a hairline plaster line or a worn skimmer gasket, and it needs a different process.

This page covers that heavier repair specifically: a fractured gunite shell, a separated cove where the wall meets the floor, or a crack that runs the full depth of the shell rather than sitting in the plaster skin. If what you're dealing with is a surface hairline or a skimmer body, our crack and skimmer repair page covers that lighter, cheaper fix instead.

Why the ground here does this to a shell

Almost every residential lot from Lake Jackson through Clute, Angleton, and Freeport sits on Beaumont clay, a heavy, fine-grained soil that expands when it takes on water and shrinks when it dries out. A normal Gulf Coast year runs through several of those cycles. Rain soaks the clay around a pool's footprint and it swells. A dry August pulls the same clay back and it contracts. A gunite shell doesn't expand and contract at anywhere close to that rate, so the ground moves relative to the shell instead of with it, and that differential movement is what eventually opens a structural crack.

Add a shallow water table on top of that. Much of this stretch of the coast keeps groundwater close enough to the surface that an empty or low pool can face real hydrostatic push from underneath, sometimes enough to crack or even lift a shell that has no active leak at all. Storms make it worse in a different way. Hurricane Harvey dropped feet of rain across Brazoria County in 2017, and the ground saturation and drainage stress that kind of event puts on a property doesn't always show up as a crack the same week. We've found shell damage on pools years after a major storm, once enough dry-wet cycles worked the existing stress point open.

How we repair a structural shell crack

1. Confirm it's structural

   Dye testing and a physical check tell us whether a crack is cosmetic plaster shrinkage or a true through-shell fracture. We look for stepped displacement on either side of the line, which is the clearest sign the gunite itself has moved.

2. Map the full extent

   A structural crack rarely stops where you can see it. We trace it along the cove, up the wall, and across the floor to find where it actually terminates before we open anything.

3. Expose and inspect the rebar

   Where the crack is wide enough to have let water and soil moisture reach the steel cage inside the gunite, we chip out around it to check for corrosion. Rusted rebar changes the repair; it has to be treated or replaced, not just covered over.

4. Structural injection or staple stitching

   Narrower active cracks get low-viscosity epoxy injected under pressure to bond the fracture from the inside out. Wider or shifting cracks get stainless steel staples set across the crack line first, tying both sides of the shell back together before any epoxy or patch goes in.

5. Re-gunite the section

   Larger structural repairs get a fresh layer of sprayed gunite over the repaired area, bonded to the existing shell, rebuilding the structural section rather than skimming over it.

6. Plaster finish and cure

   Once the structural work cures, plaster or pebble finish gets reapplied and matched to the surrounding surface as closely as the batch allows.

7. Pressure and dye retest

   We retest the repaired section once the pool refills, confirming the fix holds before we call the job finished.

What makes a shell repair harder

• Corroded rebar. Once water has tracked along a crack for months or years, rust can expand the steel cage inside the gunite, which pushes outward and widens the very crack it caused. That section has to be cut back further than the visible damage suggests.
• Deep-end cove separation. The joint where the wall meets the floor at the deep end takes the most stress from ground movement, and a crack there is harder to access and repair cleanly than one on a flat floor section.
• Layered old patches. Shells from the 1960s through the 1980s sometimes carry two or three cosmetic patches stacked over the real structural gap. Those have to come out before the actual repair can start, which adds time nobody quoted up front.
• Hydrostatic pressure during the repair itself. If the shell needs to be partially or fully drained to access a crack, the same high water table that helped cause the problem can work against the empty pool. We install or check a hydrostatic relief plug before draining any shell in this soil.
• Post-storm timing. A crack that opened during ground saturation from a major rain event sometimes doesn't show up until a dry spell pulls the clay back weeks or months later, which can make timeline questions about "when did this start" genuinely hard to answer.
• Unpermitted decking poured against the shell. Decking added without an expansion joint against the coping can transfer its own movement directly into the shell edge, a failure mode that's specific to how the deck was built, not the pool itself.

Common questions

Call (979) 320-1978 to get the shell inspected.