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How To Run PVC Pipe Under Concrete

A home renovation project may require you to run PVC pipe underneath a concrete surface. Now, you're wondering how you can complete this task. We've researched this concern for your convenience, and here's what we found.

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First, ensure that you prepare for this project by following the correct safety procedures. Next, gather the items you’ll need. After completing the initial arrangements, run your PVC pipe assembly under concrete by following these steps:

  1. Know and follow building codes
  2. Gather the necessary permits
  3. Create the entry and exit points
  4. Prepare the PVC pipeline
  5. Insert the PVC pipe
  6. Secure the connections
  7. Close the holes

Although it may look relatively straightforward, running a PVC pipe under concrete requires careful following of its steps. Continue reading as we discuss this procedure in greater detail.

Plumbing pipe coupling on concrete floor, Blue PVC pipe for water transportation by pipeline - How To Run PVC Pipe Under Concrete

Safety Precautions To Follow

Like relatively any house or property renovation project, it’s important to prepare for the upcoming task. In particular, put together safety measures to ensure the well-being of everyone involved in the project, including the people nearby.

So here are some preventives actions you can follow before you start running a PVC pipe under concrete:

  • Look at your property’s blueprints. Be careful when breaking down structures, as you might bring harm to elements that otherwise stabilize your home.
  • Document the project from the beginning. Don’t leave your actions up to chance as you may increase the risks of committing costly mistakes.
  • Keep the worksite as clean and as tidy as possible. Maintain proper organization with your equipment and materials to prevent on-site accidents and injuries.
  • Wear the proper gear. Equip yourself with safety clothing, such as a construction hat, safety glasses, and steel-toed boots while you’re at the job location.
  • Turn off the electricity. In particular, disengage the property’s main power supply if you need to go through electrical equipment when boring through concrete.

Also, don’t forget that your mental health is as important as your physical well-being. So don’t be afraid in taking breaks when you hit roadblocks while working on this project. Leave the job site, and come back when you have a clearer mind than before.

Things You’ll Need

  • Steel measuring tape
  • Shovel
  • Sledgehammer
  • Concrete mix
  • PVC pipes
  • PVC adhesive

DIY Instructions To Run PVC Pipe Under Concrete

Buried water pipe

Step #1: Know And Follow Building Codes

Make sure to read up on the right building codes for this project. For instance, chapter 3 section 301 of the general regulations imposed by the 2015 Internal Plumbing Code (IPC) mentions the ideal spacing required for PVC pipes for plumbing lines.

Step #2: Gather The Necessary Permits

Take note that certain home renovation projects without the proper certifications or permits may result in costly government fines. You can ask your local municipal office for the appropriate permits to acquire to start and maintain this particular project.

For instance, you may need a permit if the PVC pipe you're installing on your property will require extensive construction and repairs throughout the surrounding areas. On the other hand, you might not need a permit if you're only going to install a PVC line in a small area on your property.

Step #3: Create The Entry And Exit Points

After understanding the codes and gathering the necessary permits for your project, start preparing this job by measuring the amount of PVC pipe you need. Again, make sure to document the required measurements for the pipes because you don’t want them to be too long or too short.

Once you have the correct measurements, purchase the PVC pipes needed for this project if you haven’t yet. Next, lay the pipes over your desired location. You don’t need to run those lines under the concrete slab yet.

Then, use your shovel to dig the ground for the entry and exit points of your pipe assembly. Use a sledgehammer instead of a shovel if those locations are concrete instead of soil.

Warning: Be careful when using the shovel or the sledgehammer. Digging through soil or concrete deeper than necessary may bring harm to installed structures, such as existing electrical and plumbing lines.

Step #4: Prepare The PVC Pipeline

Yellow PVC pipeline for cable systems buried in the sand. Polyethylene pipes are used as channels for optical cables and providing protection for telecommunication and electrical power cables.

Bear in mind that the exact methods in this particular step often differ per person and the specific requirements for their project. However, it's ideal to assemble your PVC pipe assembly above ground.

You can also use adhesives like rubber and PVC cements to connect and secure the different parts of the assembly. Next, pour water into the hole to help soften the soil underneath the concrete.

At this point, you might also be curious if you can use silicone instead of a plumber's putty. Read our post highlighting that concern to know the answer.

Step #5: Insert The PVC Pipe

If you’re installing a new PVC pipe underneath a concrete slab, you’ll likely need to push the material through the soil under the concrete. You can use a shovel to help clear some of the ground under the concrete material.

On the other hand, if you’re replacing an old PVC pipe, you can stick the new line into the old material’s location. That way, you shouldn’t run into significant interferences as you install the new pipe.

Step #6: Secure The Connections

Once the PVC pipe assembly is underneath the concrete, and it’s in your desired location, connect it to the main plumbing line. Again, you can use your choice of adhesive for this step, but ensure that the connection is secure before you move forward.

Step #7: Close The Holes

At this point, you can test the new PVC pipe assembly if it works as intended. If it performs to your liking, cover the holes you created earlier. Pour the soil back into these openings. Otherwise, you may need to mix a fresh batch of concrete if the entry and exit points of the installation are at a concrete area.

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You can also watch this video if you need a visual reference for this project:

After going through this procedure, you might also want to learn the process to run a washing machine drain outside into the yard. If so, read our post on that concern to know the steps you need to take.

Does Concrete React With PVC Pipe?

Although concrete may stick to a PVC pipe, the bond formed isn’t usually strong. PVC pipes also expand and contract with changing temperatures. This movement can help remove the bond from the concrete, allowing the pipe assembly to remain safe from unwanted pressure and strain.

Does PVC Deteriorate Underground?

PVC can still deteriorate underground. However, the material can be safe from harm from other sources, such as harsh UV rays.

Also, proper installation is often vital to ensure the underground PVC assembly lasts long. It’s because improper installation practices can lead to PVC failure.

How Deep Can PVC Pipe Be Buried?

Plumbing pipe coupling on concrete floor, Blue PVC pipe for water transportation by pipeline

You can bury quality PVC materials to a maximum depth of 50 feet. Some high-quality options exist that you can bury even deeper.

How Much Weight Can A Buried PVC Pipe Hold?

The maximum strength a buried PVC pipe can withstand often depends on factors like the quality of its construction and its diameter. For example, a Schedule 40 PVC pipe with a 0.50-inch diameter should be strong enough to hold about 264 pounds. But a Schedule 80 PBC pipe with an 8-inch diameter might be able to hold about 17,332 pounds.

What Causes PVC Pipes To Break Under Concrete?

Repair and replacement of broken waste water pvc plastic sewer pipe, drainage of waste water from the house. Close-up

As mentioned earlier, improper installation can become a prime suspect to PVC pipes having shorter serviceable lives than intended. Other reasons that can cause these materials to break under concrete are:

High Water Pressure

PVC pipes, particularly those used for plumbing, can only often handle water pressure up to 80 psi. Water pressure higher than that measurement may cause the materials to expand, leading to cracks and breaks.

Sunlight Exposure

PVC pipes that become exposed above ground can be susceptible to harm from the sun’s harmful UV rays. Exposure to these rays may cause PVC to become brittle, making it susceptible to issues like cracking. Color fading may also occur from significant UV light exposure to PVCs.

Soil Erosion

The ground surrounding a PVC pipe assembly may shift because of natural causes. If so, this movement may place unwanted pressure on specific locations on the pipe setup, which may lead to breaks.

You can also watch this clip to gain additional insights into the different reasons why PVC pipes may break underneath concrete:

Final Thoughts

Take your time in going through the different steps to run a PVC pipe assembly under concrete. Follow the steps mentioned in this post and don’t forget to document your progress. If done correctly, your new PVC pipeline should work as intended.