How To Dig Under A Concrete Slab

How To Dig Under A Concrete Slab
  • Author: Amanda Arnold
  • Posted On: October 5, 2022
  • Updated On: August 21, 2023

The two most frequent causes of digging under a concrete slab are installing an irrigation system or outdoor lighting. A supply line will probably need to be run under an existing hard surface for either job. One technique is to dig a trench by removing a piece of concrete or asphalt, but there are other, less dramatic options.

The use of water’s power to carve a hole in a barrier is the most effective and economical method of doing so. Use the required fittings to join a garden hose to one end of a piece of PVC pipe and a jet nozzle to the other.

The force of the water will rip a hole through to the other side that is precisely the same size as your PVC pipe. The length of the PVC pipe can be changed to excavate large or small regions. A coupler can be added to the PVC pipe to allow the tool to be reused repeatedly.

The Process Of Digging Under A Concrete Slab

It is advisable to use water pressure to drill through the soil. This is one such strategy that needs a little extra equipment. Before digging a tunnel beneath a concrete slab, dig the necessary trenches on either side of the obstruction.

  • Build a water drill. Therefore, the PVC pipe should be cut to four and a half feet length longer than the concrete slab’s width. If two pipe lengths need to be joined, do so. Using pipe cement, join a PVC female hose adapter to one end and a male hose adapter to the other.
  • Attach a high-pressure hose nozzle, such as a sweeper, to the male end. Connect the garden hose to the female adaptor. Put the water drill’s nozzle tip against the trench’s end and place it into the trench from one side. Turn on the water firmly.
  • Put pressure on the soil by inserting the drill’s tip into the end of the trench. Push the drill beneath the concrete slab repeatedly until the tip emerges from its other side. And then, move the drill back and forth to remove debris from the hole.
  • Using a PVC cutter or saw, remove the adapters. The pipe must be connected to the rest of the system.

Elements Needed To Dig Under A Concrete Slab

  • The brass 2-inch sweeper nozzle
  • PVC male hose end adapter fitting.
  • Brass 3 or 4-inch female hose to 3 or 4-inch female pipe swivel
  • Brass a three or 4-inch male hose to a three or 4-inch female pipe.
  • PVC glue
  • Garden hose

Using A Sidewalk Sleever To Run Pipe Under A Concrete Slab

Firstly, place a piece of pipe next to the concrete slab Sleever so that one end is in contact with the pipe stop, then use your finger to mark the spot where the pipe just touches the tapered end. Afterward, cut the pipe there. During installation, dirt might enter the pipe if it extends past the tapered end.

Slide the cut-off pipe onto the concrete slab Sleever. The concrete slab Sleever should be kept tidy. Removing the tool if it is covered with dirt will require much effort. Just below the concrete, tamp in a few inches with the Sidewalk Sleever. The tool will hold itself off the ground.

As a result, installing the tool and removing it once it is in place is simpler. Use a sledgehammer to strike the concrete slab Sleever buried beneath the concrete slab while standing on the edge of the trench. Keep pounding the tool when the tapered end is visible at the opposite end.

Grab the tool’s end and remove it from the installed pipe once the tool and pipe are visual at the other end. If it’s crucial, use the hammer to tap the tool’s pointed end to aid the concrete slab Sleever exit from the pipe.

Filling A Space Under A Concrete Slab

Under concrete slabs, cavities can be filled with sand-cement grout. To fill in the gaps, holes are drilled, and the sand, cement, and water mixture are pushed through them. Slab jacking is a cost-effective way of restoration, but there are some significant downsides.

One of the best base materials for concrete slabs is crusher run, a mixture of crushed stone and stone dust. The other is coarse aggregate. Most concrete contractors use a blend of coarse and fine aggregate for a durable base that will be secure for settlement and drainage.

Final Installation Step

Although the speed of the installation can vary depending on the soil and experience, in this case, the pipe was put in under 60 seconds.

Once the pipe is inserted, it can be continued by gluing on to it, a smaller pipe can be threaded through it, or the pipe can be used as a sleeve for wires. Repeat the procedure to install as many pipes and many sleeves as necessary. This is an easy way to dig under a concrete slab without any high budget.


For some homeowners, digging beneath their concrete slabs is preferable. As was already said, one significant benefit is that the house floor is not damaged or made a mess. If you recently refinished your flooring, you probably don’t want to go back and undo all that labor-intensive work.

If you are remodeling, intend to renovate, or don’t want your property to look like a disaster zone, making it temporarily unlivable, under-slab digging may be a fantastic solution.

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Author: Amanda Arnold

Amanda has been working with ConstructionHow since 2021. Her experience spans over 5 years in the creative niche such as home decor and trends, landscaping, renovations, and custom architectural values. As a home designer expert, she has a keen eye for the latest home improvement trends with accurate facts that readers find impossible to ignore. Being invested in home-building trends is how she has gained her lucrative expertise exploring more to bring a positive ambiance for all homeowners (and even tenants!). Currently, she lives in a beautiful beach home, a source of fascination for her.