How to Repipe a House on a Slab

Repiping a house on a slab is a significant home improvement project that involves replacing the plumbing pipes located beneath the concrete foundation. This type of repiping is common in homes with concrete slab foundations, and it becomes necessary when the existing plumbing system starts showing signs of deterioration, leaks, or reduced water pressure. 

How to Repipe a House on a Slab

Repiping a house on a slab requires careful planning, professional expertise, and adherence to safety protocols. In this comprehensive guide, we will walk you through the step-by-step process of how to repipe a house on a slab of repiping a house on a slab, from preparation to completion.

Needed Materials

Copper, PEX, or CPVC Pipes: 

Depending on your preference and budget, choose the appropriate type of pipes for the repiping project. Copper pipes are durable and resistant to corrosion, while PEX and CPVC pipes offer flexibility and ease of installation.

Pipe Fittings and Connectors: 

Get a variety of fittings, such as elbows, tees, couplings, and adapters, to create a functional plumbing network.

Hangers and Clamps: 

Secure the new pipes to the slab using hangers or clamps to prevent movement and damage.

Pipe Insulation: 

Insulate the pipes to protect them from temperature changes and prevent condensation.

Pipe Cutter or Saw: 

Use a pipe cutter or saw to cut the pipes to the required lengths accurately.

Use a Pipe Cutter or Saw to Cut the Pipes

Pipe Wrenches or Adjustable Pliers: 

These tools are essential for tightening and connecting pipe fittings securely.

12 Step-by-step Guidelines on How to Repipe a House on a Slab

Step 1: Inspection and Assessment

Before beginning the repiping process, conduct a thorough inspection of the existing plumbing system to identify any issues or areas that require attention. Look for signs of leaks, corrosion, and poor water flow. Also, assess the layout of the current plumbing system to determine the best approach for the repiping project.

Step 2: Obtain Necessary Permits

Contact your local building department to inquire about the required permits for a repiping project. Most municipalities have specific regulations governing plumbing work, and obtaining the necessary permits is crucial to ensure that the work is done safely and up to code.

Step 3: Prepare the Work Area

Clear the work area around the slab foundation and ensure that it is accessible to the plumbing professionals. Move furniture, rugs, and any other items away from the working zone. It is essential to provide a clean and unobstructed workspace to facilitate the repiping process.

Step 4: Turn Off the Water Supply

Locate the main water shut-off valve and turn off the water supply to the house. This step is critical to prevent any water flow during the repiping process, reducing the risk of flooding or accidents. If you cannot locate the main water shut-off valve, contact a professional plumber. But never try to repipe with the water supply still on.

Locate the Main Water Shut-off Valve

Step 5: Excavate Trenches

Using appropriate excavation equipment, dig trenches around the perimeter of the house where the new plumbing pipes will be installed. The trenches should be wide and deep enough to accommodate the new pipes comfortably. However, be careful not to damage the plumbing system, wiring, and other utilities buried beneath the slab.

Step 6: Remove Old Pipes

With the trenches dug, remove the old plumbing pipes carefully. This may involve cutting the pipes and extracting them from the slab. Dispose of the old pipes responsibly, adhering to local waste disposal regulations. Although removing the old pipes can be a challenging job, it is a necessary step to complete the repiping process accurately.

Step 7: Install New Pipes

Begin laying the new plumbing pipes in the trenches. Depending on the layout of your plumbing system, you may use copper, PEX, or CPVC pipes for the repiping. Copper is known for its durability, while PEX and CPVC are more flexible and easier to work with. But make sure to use the type of pipes that is compatible with your existing plumbing system.

Step 8: Secure and Insulate Pipes

Once the new pipes are in place, secure them to the slab using appropriate hangers or clamps. Properly insulate the pipes to prevent heat loss and protect them from potential damage. This step is essential to ensure that the pipes last long and perform efficiently. It also helps maintain a comfortable indoor temperature.

Using Appropriate Hangers or Clamps

Step 9: Connect the Pipes

As you lay the new pipes, make the necessary connections to ensure a smooth flow of water throughout the plumbing system. Use appropriate connectors, fittings, and valves to create a fully functional network. However, make sure to adhere to local plumbing codes while connecting the pipes.

Step 10: Pressure Test

Before covering the trenches, conduct a pressure test on the new plumbing system. This test ensures that there are no leaks or weaknesses in the newly installed pipes. Fix any issues detected during the pressure test before proceeding. It is also important to visually inspect the pipes and fittings once again.

Step 11: Backfill the Trenches

Once the pressure test is successful, backfill the trenches carefully. Use appropriate fill material and compact it evenly to avoid settling and shifting of the soil. But make sure that the new pipes are protected from any damage during the backfilling process. Finally, restore the work area to its original condition.

Step 12: Final Inspection

After completing the repiping work, schedule a final inspection with your local building department to ensure that the project meets all safety and plumbing code requirements. Address any concerns or feedback provided by the inspector.

Following these steps on how to repipe a house on a slab can help you safely and effectively complete the project. With proper planning and professional assistance, your home will be equipped with a reliable plumbing system for many years to come.

Good luck with your repiping project!

Frequently Asked Questions

Q1: How Do I Know if My House on a Slab Needs Repiping?

A1: There are several signs that indicate your house on a slab may need repiping. Common signs include recurring leaks, water stains on walls or ceilings, low water pressure, discolored water, strange odors, and corroded or deteriorating pipes. If you notice any of these issues or if your plumbing system is several decades old, it’s essential to have a professional plumber inspect your pipes to determine if repiping is necessary.

Q2: How Long Does It Take to Repipe a House on a Slab?

A2: The time it takes to repipe a house on a slab can vary depending on the size of the house, the complexity of the plumbing system, and the extent of the repiping needed. Generally, repiping a house on a slab can take anywhere from a few days to a week or more. Factors such as the number of bathrooms, the accessibility of the pipes, and any unexpected challenges that arise during the process can also impact the timeline.

Q3: What Type of Pipes Should I Use for Repiping a House on a Slab?

A3: There are several types of pipes commonly used for repiping a house on a slab. Copper pipes are known for their durability and resistance to corrosion, making them a popular choice. PEX (cross-linked polyethylene) pipes are flexible and easy to install, making them suitable for various plumbing layouts. CPVC (chlorinated polyvinyl chloride) pipes are another option known for their affordability and resistance to chemical corrosion. Each type of pipe has its advantages and disadvantages, and the best choice depends on your budget, local building codes, and personal preferences.

Q4: Can I Repipe My House on a Slab Myself, or Should I Hire a Professional?

A4: Repiping a house on a slab is a complex and labor-intensive task that requires specialized knowledge and tools. Unless you have significant experience with plumbing and construction, it is not recommended to attempt repiping on your own. Mistakes during the repiping process can lead to costly damages, leaks, and safety hazards. Hiring a licensed and experienced professional plumber is the best way to ensure that the repiping is done correctly, up to code, and with minimal disruption to your home and daily life.

Hiring a Licensed and Experienced Professional Plumber

How Much Will It Cost?

The cost of repiping a house on a slab depends on numerous factors such as the size of the house, the type of pipes used, and any additional work that may be needed. On average, it can cost anywhere from $3,000 to $15,000 or more depending on these factors. It is important to work with an experienced plumber who can assess the project and provide a more accurate cost estimate. Also, be sure to finetune the project budget to account for any unexpected expenses that may arise.


Repiping a house on a slab is a complex undertaking that requires meticulous planning and expert execution. By following this step-by-step guide, you can ensure a successful repiping project that improves the plumbing system’s efficiency and longevity. Remember to work with licensed and experienced plumbing professionals to achieve the best results while adhering to safety and building regulations.

A well-executed repiping job will provide your home with a reliable and durable plumbing system, offering peace of mind for years to come. Thanks for reading this article on how to repipe a house on a slab.

You Can Check It Out To Loosen a Pipe Without a Wrench

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Enrique Howard

Hi, I am Enrique. I started my professional life as a handyman and did a lot of external and internal repair of home and office with a little bit of electric and plumbing support. I have extensive experience in tools testing such as drilling, turning, milling, and non-conventional machining like EDM. So let me help you on your journey towards becoming an enlightened DIYer with amazing tools that you can use on your project.

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