Hydrostatic Plumbing Testing: What It Is and Why It Matters for Your Home’s Foundation
Most homeowners don’t think much about what’s going on beneath their home—until something goes wrong. You might spot a crack in the wall, notice your floors are a little uneven, or wonder why doors are sticking when they used to swing just fine. It’s easy to assume the problem is just the shifting Texas soil (which, to be fair, is usually involved), but here’s the part most people don’t expect: sometimes the issue starts with your plumbing.
Specifically, what’s under your slab.
Let’s back up. Underneath most homes in the Dallas–Fort Worth area is a concrete slab foundation. It’s a solid base, but it’s only as strong as what’s going on beneath it—namely, the soil and the plumbing. If your home has a leak in a sewer or drain line under the slab, you may not see water, hear dripping, or even notice anything wrong with your fixtures. But over time, that hidden leak can start softening and shifting the soil beneath your house. And when that soil moves, your foundation starts to move too.
This is where hydrostatic plumbing testing comes in.
Put simply, a hydrostatic test checks to see if any of your underground plumbing is leaking. It’s not invasive. A technician plugs the main sewer line, fills it with water, and then watches to see if the water level holds. If it drops, there’s a leak somewhere under the slab. If it holds, you’re good to go.
Now, in the past, this kind of testing was something you’d have to coordinate separately—calling a plumbing company, hoping they could sync up with your foundation crew, and juggling quotes and schedules. That’s why we brought it in-house. Cable Plumbing is a trusted member of the Atlas Foundation family, which means we can handle everything—from the first sign of foundation movement to the final plumbing fix—without you having to chase anyone down or play project manager on your own home.
Why does this matter? Because plumbing and foundation problems don’t happen in isolation. A cracked sewer line can cause soil to swell, sink, or erode, which shifts your foundation. And if you’re repairing a foundation without checking the plumbing, you might be missing the root of the problem. Even worse, foundation work itself—especially lifting and leveling—can sometimes put pressure on old or brittle pipes. That’s why we often recommend a hydrostatic test after foundation repairs, just to make sure everything stayed intact underneath.
And it’s not just about repairs. If you’re buying a home, seeing new cracks in an older one, or living in an area with heavy soil movement (which is most of North Texas, let’s be honest), a hydrostatic test is one of the smartest ways to get peace of mind. It’s quick, affordable, and gives you a clear answer to a big question: Is water quietly wrecking my foundation from below?
The good news is, you don’t have to figure all this out on your own. When you call Atlas, we don’t just look at surface-level symptoms—we take a whole-home approach. That includes working hand-in-hand with our team at Cable Plumbing to get eyes (and ears, and test gauges) on what’s happening beneath your slab.
Whether you’re dealing with active foundation damage, trying to prevent it, or just want to be proactive, hydrostatic plumbing testing is one of the most overlooked tools in the toolbox. But once you understand how much it can reveal—and how easily we can handle it for you—it becomes a no-brainer.
After all, your home is only as strong as what it sits on. And that means checking the ground and the plumbing beneath your feet.
FAQ
Q: Is this something Atlas does directly?
Yes it is. Hydrostatic testing is handled by Cable Plumbing, a trusted member of the Atlas Foundation family. Because we work together under one roof, there’s no guesswork, no third-party scheduling hassles, and no finger-pointing between contractors. If you’re already working with Atlas on a foundation issue—or even if you’re just calling with concerns—we can bring in our plumbing team to run a hydrostatic test quickly and professionally. It’s all part of our commitment to keeping things simple, seamless, and done right the first time.
Q: Will I know if I have a leak under my slab?
Not always. That’s the tricky part. Many under-slab leaks don’t show up as wet spots or backups. They might not affect your water bill or your fixtures. But they can still be slowly softening the soil beneath your home, which leads to foundation movement over time.
Q: When should I get a hydrostatic test?
We recommend testing if you’ve had recent foundation work, if you’re seeing signs of foundation settling, if you suspect a plumbing issue, or if you’re buying a home with known soil movement. It’s also smart after a major plumbing repair—just to be sure everything stayed sealed.
Q: What happens if there is a leak?
Don’t panic. Cable Plumbing can scope the line with a camera to find the exact location of the problem. In many cases, it’s just a small section of pipe that needs to be repaired. Once the plumbing is fixed, Atlas can reassess the foundation to make sure it hasn’t been compromised.
Glossary
Hydrostatic Plumbing Test
A simple pressure test where the sewer line is filled with water and monitored for leaks. It helps detect under-slab plumbing failures before they cause major foundation issues.
Under-Slab Leak
A break or crack in a sewer or drain line that runs beneath a home’s concrete foundation. These leaks are hard to detect but can seriously damage the soil—and the foundation—over time.
Slab Foundation
A flat concrete base that a home is built on. Most homes in North Texas sit on slab foundations, which are especially vulnerable to soil movement and underground moisture.
Soil Movement
Changes in the ground beneath a home caused by moisture changes, drought, heavy rains, or leaks. North Texas soils—especially clay—are notorious for expanding and contracting with water, which can shift a home’s foundation.
Cable Plumbing
Atlas Foundation Inc.’s in-house plumbing team. Cable Plumbing handles hydrostatic testing, leak detection, and under-slab plumbing repair as part of Atlas’s whole-home approach to foundation protection.