You're wiping down the counter and the water doesn't stop at the wall. It runs off the back edge and disappears somewhere behind the stone. You lean in, and there it is, a dark line where the countertop meets the wall that you would swear was not there last year.
Before you start pricing foundation repair, know that most of these gaps have been there since the day the counter went in.
Stone Doesn't Bend and Your Walls Were Never Straight
A slab of quartz or granite gets cut flat and it stays flat. The wall behind it is drywall hung over studs, and no wall in any house is perfectly straight or perfectly plumb. Put a rigid thing against a wavy thing and you get a gap that changes width as it runs. Fabricators know this, which is why they scribe the back edge where they can and fill the rest with caulk. The Natural Stone Institute treats about an eighth of an inch as normal and most installers work to a quarter.
So the counter went in with a gap, somebody ran a bead of caulk down the joint, and you stopped seeing it. Then that caulk spent five or ten years taking heat off the range, steam off the dishwasher, hard North Texas water, and somebody scrubbing at it with a rough sponge twice a week. Eventually it shrank, lost its grip on one side, and pulled back off the stone. The gap is old news. The caulk is what finally quit.
How to Tell If Anything Is Actually Moving
Four minutes with a tape measure settles this.
Measure the gap at both ends of the run and once in the middle. Write the three numbers on a strip of masking tape and stick it inside the cabinet door. Take a photo on your phone so the date rides along with it. Then check the same three spots in a month.
A gap that reads the same next month as it does today is a caulk job and nothing more. One that's picked up a sixteenth at one end is worth paying attention to.
The shape tells you something too. An even gap down the whole run is almost always just the wall being wavy. A wedge, tight at one end and open at the other, means the cabinet run isn't sitting level anymore, and cabinets only go out of level when what's underneath them moves.
One symptom on its own is not a story, so go walk the rest of that side of the house. Are the interior doors catching on the jamb. Has the grout opened up anywhere. What you're really looking for is a crack running at an angle up from the corner of a doorway, because that one travels with the same movement. Three of those on the same wall is a pattern, and that's a different conversation than a gap behind the counter. You read it the same way you'd read a new crack in your drywall, which most of the time turns out to be a lot less than it looks like.
Why Everybody Notices This in Late Summer
Allen sits on Blackland Prairie clay, and that soil moves with moisture more than almost any soil in the country. It swells when it's wet and shrinks when it's dry, and by the end of August in Collin County it's about as dry as it gets. Soil moisture across North Texas has been sitting below the tenth percentile for most of 2026.
When the clay under the edge of a slab shrinks, the slab edge settles a little. The cabinets sitting on it tip a hair, the counter tips with them, and the gap at the wall opens up at one end. Then the fall rains come, the clay swells back, and a good bit of what you're looking at closes on its own. That's why we tell people not to do anything permanent about it in September.
The most useful thing you can do costs about twenty dollars. Run a soaker hose 12 to 18 inches out from the slab and give it twenty minutes a few times a week through the dry stretch. Steady is the whole goal. The clay handles constant damp fine, and it's the swing between soaked and cracked that moves your slab, so consistency beats volume every time. Under NTMWD rules soaker hoses and drip lines are exempt from the twice-a-week spray restriction, so you can keep it on a schedule even in a stage three summer.
This is the same stretch of the year that has people asking us why their vinyl plank floor is buckling. Same soil, same heat, different symptom.
What Actually Fixes It
Up to about a quarter inch, this is a Saturday morning job and you don't need us for it.
The part people skip is removal. Pull every bit of the old caulk out with a plastic scraper and a fresh utility blade, get both surfaces clean and dry, and only then run the new bead. Caulking on top of old caulk is the single reason a second bead fails faster than the first one did.
Use silicone or a silicone hybrid. The painter's acrylic in the white tube tools beautifully and cracks by spring. Get it color matched to the stone or to the wall, whichever you'd rather be looking at every morning. If the gap is wider than a quarter inch, push a foam backer rod in first so the caulk has something to sit against instead of sinking into the void behind it.
Past about half an inch, caulk stops being the answer, because a bead that thick sags and splits. That's where a scribed filler strip or a low piece of the same stone does the job, cut to follow the wave in the wall. If you've still got a remnant from the original job, a fabricator can usually cut that piece out of it.
Sometimes the answer is that the top has to come off and the boxes underneath have to be shimmed level before it goes back down. That's real work and it isn't cheap, so nobody should be recommending it to you off a photo. When we set countertops we level the cabinet boxes first, even where the floor under them has already moved, because stone set on a run that isn't level will open the same gap again no matter how good the caulk is. The cabinets are what carry the counter, and that's the part people forget while they're standing there staring at the stone.
When It's Worth Having Somebody Out
If the gap measurably changed over a month, have someone look at it. Same goes if it's wedge shaped and there are doors sticking on that side of the house. The one that actually needs moving on is water getting back there, because most cabinet decks are particleboard under the laminate, and once that swells you've gone from a cosmetic problem to a real repair.
One more thing. Don't call a foundation company first. They'll look at your house through the one lens they own, and you'll have a number before you've got a diagnosis. Have somebody check the counter and the cabinets, find out whether the run is still level, and then you'll know whether there's a foundation question here at all. In most Allen kitchens there isn't.
While you're down there looking closely at your counters this month, the other thing homeowners around Twin Creeks and Suncreek ask us about in August is whether their quartz is fading by the window.
If you want somebody to put a level on your cabinet run and tell you straight what you're looking at, call us at (469) 242-3276. We've been doing countertops in Allen since 2010 and we've caulked a lot more of these gaps than we've re-set. If it's a caulk job you'll hear that from us, even though it isn't the job we'd rather be selling you.