Cost to Replace Cast Iron Pipes [2024 Data]
Normal range: $375 - $900
The average U.S. homeowner spends $650 on replacing cast iron pipes, but the cost ranges from $375 to $900, depending on the location, size, and scope.
The cost to replace cast iron pipes is $650, but homeowners typically spend anywhere from $375 and $900 to swap out the old pipes. How much you’ll pay varies by the length of the pipe, accessibility, and more. Our guide breaks down what goes into replacing cast iron pipes to help you budget accordingly.
- Average
- $650
- Low end
- $125
- high end
- $1,800
Cast Iron Pipes Replacement Cost by Location
The cost of replacing cast iron pipes depends on the location of the pipes that need replacing. While you can determine the cost of replacing cast iron pipes by the linear foot, some projects are more intensive than that and require trenching, reconstruction, repaving, and more. Here are some of the most common locations and average replacement costs:
| Pipe Location | Average Cost Range |
|---|---|
| Bathroom sink replacement | $200–$800 |
| Basement overhead sewer line | $8,000–$10,000 |
| Kitchen sink pipe | $150–$500 |
| Main water line | $650–$2,800 |
| Sewer trap | $1,500–$3,000 |
| Under a slab | $3,000–$20,000 |
Size of Cast Iron Pipes
The average cost of cast iron pipes is between $10 and $20 per linear foot for the material, with an additional if you include labor. Most pipes range from 10 to 60 linear feet, with the average length falling at the 30-foot mark. Total costs with labor range from $125 to $1,800 depending on the length, so here’s a breakdown by size.
| Cast Iron Pipe Size (Linear Feet) | Average Material Cost | Average Cost with Labor |
|---|---|---|
| 10 | $100–$200 | $125–$300 |
| 20 | $200–$400 | $250–$600 |
| 30 | $300–$600 | $375–$900 |
| 40 | $400–$800 | $500–$1,200 |
| 50 | $500–$1,000 | $625–$1,500 |
| 60 | $600–$1,200 | $750–$1,800 |
Plumber Costs
Most cast iron pipe replacement projects require a professional plumber. You’ll find that plumbers typically mark up the material cost of cast iron pipes by 25% to 50% depending on the cost of living in your area and the project scope. This means cast iron pipes cost between $12.50 and $30 per linear foot with labor or $2.50 to $10 extra per foot. Here are several other tasks your plumber might complete:
Burst pipe repair: $500
Sewer cleanout cost: $2,000
Installing a sink: $450
Rough-in plumbing for a bathroom: $6,500
Landscaper Costs
If your main water line or sewer line needs replacing, you may need to hire a landscaping company near you to clear the way for a plumber to go in and replace the cast iron pipes. Professional landscaping costs range anywhere from $1,250 and $6,000 and can vary wildly based on the topography, soil composition, and obstacles in your yard.
Boulder removal cost: $650 to $1,200 per boulder
Tree removal cost: $200 to $2,000 per tree
Pavement paving cost: $2 to $15 per square foot
Additional Cost Factors
Several other factors can impact the cost to replace cast iron pipes, including sewer line inspections, old pipe removal, permits, accessibility, and post-construction cleanup expenses. Let’s break down each of these cost factors.
Sewer Line Inspection
The cost of a sewer line camera inspection ranges from $250 to $1,600. If you know there’s a leak or issue with your cast iron pipes but don’t know the source of the issue, a pro may conduct a sewer line inspection to pinpoint the exact location of the plumbing problem and strategically replace just the problematic cast iron pipes.
Old Pipe Removal
To remove old pipes, your pro may need to demolish and repair your walls, ceiling, yard, or pavement to access the pipes. This can greatly increase the cost of the project. Here are a few price estimates depending on the type of preparation needed to remove cast iron pipes:
Ceiling repair costs: $450–$1,700
Drywall repair cost: $300–$925
Trench cost: $400–$1,200
Permits
Plumbing permits cost anywhere from $50 to $500. You may need a permit for a major plumbing project such as replacing plumbing external plumbing lines or lines under a foundation. It’s a good idea to check with your local building department to see if you need to get a permit first. You can also ask your plumber if they can obtain a permit for you. Many plumbers include getting permits as part of their plumbing replacement quotes.
Post-Construction Cleanup
Junk removal costs range from $60 and $700 on average and depend on the number of pipes you’re replacing. While some pros offer removal services for the old pipes, others might use a third party or refer you to a junk removal company in your area.
Accessibility
You'll pay more per linear foot to have a plumber work in hard-to-reach areas of your home. For example, if your cast iron pipes are in the crawl space, under your foundation, or require trenching and landscaping services, then you'll likely pay on the higher end of the price range than an easily accessible area like under the kitchen sink.
Remember that if your cast iron pipe replacement project requires repairing drywall and other structures in your house, it can further increase the cost of your project.
DIY Replacing Cast Iron vs. Hiring a Pro
DIYing minor cast iron replacement projects could save you anywhere from 25% to 50% of the project cost, or between $75 and $300 on labor costs for a typical 30-foot cast iron pipe. While you might be able to replace a simple cast iron pipe in your kitchen or bathroom sink, most major cast iron replacement projects require a licensed plumber to tactfully complete the project. In some municipalities, you might even need a license for certain plumbing projects.
For this reason, we recommend working with a local plumber—especially if you’re replacing the main sewer line in your home. To ensure you find the best plumber for the job, be sure to vet your pros carefully and compare quotes and services from at least three contractors.
Cast Iron Pipes Replacement vs. Repair
Replacing cast iron pipes may not be your only option if you’re hoping to save money—in some cases, you can repair your cast iron pipes. Main water repair costs are $300 to $1,100 less than replacing the pipes, ranging from $350 to $1,700 on average.
You’ll need to consider the age and condition of your cast iron pipes and have a professional plumber inspect the pipes to determine if repairing vs. replacing the plumbing is possible. Pipes that are more than 25 years old, or pipes that have extensive damage, are better off replacing entirely. A good rule of thumb is the 50% rule. If repairing cast iron exceeds 50% of your replacement cost, your best bet is to replace them.
How You Can Save Money While Replacing Cast Iron Pipes
Before you take out the checkbook and sign off on a price, these tips could help you save on the cost of replacing cast iron pipes.
Conduct a sewer line inspection to replace or repair the pipes that need it rather than all cast iron pipes.
Clear your yard or home to make replacing cast iron pipes more accessible to your pros.
Repairing cast iron pipes that are still in decent condition and aren’t over 25 years old can help you save on the cost of replacing the pipes entirely.
Use a trenchless sewer replacement method to avoid extra trenching and landscaping repair costs.
Consider replacing your cast iron pipes with a more budget-friendly replacement material like PVC.
Check your homeowners insurance policy or HOA to see if they’ll cover damage associated with your cast iron pipes.
Does Replacing Cast Iron Pipes Increase Home Value?
Replacing old, outdated cast iron pipes can definitely increase your home’s value, but just how much ROI you’ll see depends on many factors, including:
Safety: If your old pipes have caused water leaks, mold issues, or worse, structural problems, then replacing these faulty pipes and repairing the damage they caused will increase your property’s value.
Functionality: Cast iron pipes aren’t common in newer constructions because they’re prone to rust and corrosion, blockages, the freeze-thaw cycle, and breakages over time. If you live in a colder region, here’s a winter plumbing tip: replacing outdoor cast iron pipes with PEX pipes could give you the biggest return on your investment, as your pipes are less likely to freeze and burst.
Efficiency: If you replace cast iron pipes with copper, you could see a larger ROI because copper is durable and can handle hot water or cold temperatures.
How Angi Gets Its Cost Data
Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We extensively research project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We rely on reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.
Want to help us improve our cost data? Send us a recent project quote to costquotes@angi.com. Quotes and personal information will not be shared publicly.
Frequently Asked Questions
Replacing cast iron pipes when they’ve reached the end of their life span is key to preventing leaks and clogs. Over time, cast iron pipes corrode and experience pipe scale, which thickens the inside of the walls and increases the chance of clogs while also decreasing water flow. As the material deteriorates, you could experience costly leaks that increase reparation expenses.
Cast iron can last between 50 and 75 years, but it’s still a good idea to check for leaks as your pipes approach the 25-year mark, as pipes can already show signs of deterioration within the first three decades.
For easy-to-access pipes, your plumber will shut off the main water line and replace the pipes without demolishing your property. Underground or difficult-to-access pipes require different approaches. There are two ways to replace underground cast iron pipes: trench and trenchless sewer line replacements. Trenchless replacements result in minimal damage to your yard and involve bursting pipes and replacing them with new ones via an access point.
Replacing cast iron pipes can take anywhere between a few hours to more than five weeks to complete, depending on the project's scope. Small projects like simply replacing a pipe in your kitchen or sink can be accomplished in one day. Meanwhile, extensive underground projects will take much longer to complete and are weather-dependent.