A slab leak is a supply line leaking beneath a concrete slab foundation. It is its own service because both the finding and the fixing are different from a leak inside a wall. The line is encased in or run under concrete, so it cannot be seen, and the repair choices, reroute, open-and-spot, or pipe coating, each have a place.
In Arvada slab leaks have a specific driver. The expansive Pierre Shale and bentonite clay under the Front Range swells when wet and shrinks when dry, and that seasonal movement flexes the slab and the lines cast into it. Over years that stress works copper against concrete and opens a leak. Hot-water lines fail first, because heat makes copper move more.
Finding a leak you cannot see or reach
Detection under a slab is careful work. We isolate the hot and cold lines by pressure to prove which side is leaking, then use acoustic equipment tuned to the sound of water escaping under concrete, cross-checked with thermal imaging that reads the warm track of a hot-line leak through the floor. The result is a marked point, not a general area.
That precision is the whole game with a slab leak. The difference between a located leak and a guessed one is the difference between opening one square of concrete and trenching a room. We do not open the floor until two methods agree on the spot.
| Repair option | Best when | Trade-off |
|---|---|---|
| Spot repair | One leak, sound pipe | Opens slab at the point |
| Reroute | Repeat risk, leak under tile | New line in walls or attic |
| Pipe coating | Suitable line, avoid opening floor | Case-dependent, needs assessment |
Choosing reroute, spot repair or coating
Once located, there are three honest paths. A spot repair opens the slab at the leak and replaces that section, best when the pipe is otherwise sound and the leak is a one-off. A reroute abandons the failed under-slab run and routes new line through walls or the attic, best when the old line is likely to fail again or the leak sits under finished tile. Pipe coating restores a line from the inside without opening the floor in the right cases.
We walk through which fits your house and your slab rather than defaulting to the biggest job. On a newer west Arvada home with one hot-line failure, a spot repair may be right. On an older slab with a second leak, a reroute usually costs less over time than opening the floor twice.
The expansive-clay pattern under Arvada slabs
Homes on slab-on-grade foundations across the metro sit on soil that the Colorado Geological Survey maps as expansive. When that clay takes on water, from irrigation, poor drainage, or the leak itself, it swells with real force and pushes up on the slab. When it dries, it shrinks and the slab settles. That constant flexing is what shears a line that was fine for fifteen years.
It is also why fixing the leak is only half the job. We check drainage and grading around the foundation, because a downspout dumping against the slab keeps the clay cycling and sets up the next failure a few feet away.
Slab Leak Detection & Repair: related work and areas
Slab Leak Detection & Repair: common questions
How do I know if I have a slab leak and not a wall leak?
Tell-tale signs are a warm spot on the floor from a hot-water line, the sound of running water with everything off, unexplained damp or cracked flooring, and a bill that climbed. We confirm it by isolating the slab lines under pressure, so we know it is under the concrete before opening anything.
Do you have to jackhammer my whole floor?
No. A located slab leak is opened at a single point for a spot repair, or bypassed entirely with a reroute that leaves the floor closed. The reason we invest in precise detection is to avoid opening more concrete than the leak actually requires.
Why do slab leaks happen so often on the Front Range?
The expansive clay under the metro swells when wet and shrinks when dry, and that movement flexes the slab and the lines cast into it until a joint or a worn spot gives. Hot-water lines fail first because heat makes copper expand and rub against the concrete. It is a soil-and-movement problem more than a pipe-quality one.
How much does slab leak repair cost in Arvada?
A single spot repair on an accessible line is the low end. A reroute or a leak under finished tile costs more because of access and restoration. We give the repair options with ranges after the leak is located, and we recommend the least invasive fix that will actually last, not the largest one.
Are you licensed to open a slab foundation?
Yes. Slab work is done by licensed, insured Colorado plumbers, and any concrete cutting is done to code and properly restored. License details are available on request before work begins.
Need slab leak detection & repair in Arvada?
Call a licensed local plumber who works Arvada every day. No forms, no callback queue.