Pipe Relining vs. Pipe Replacement: Which Sewer Repair Option Is Right for Your Property?

When an underground pipe fails, you often face two options: reline it from the inside or dig it up and put a new one in its place, and neither is a safe default. 

If you choose relining because it costs less and is minimally invasive, even when the damage calls for a complete replacement, you end up paying for a repair that won’t last long. Similarly, going for a replacement when relining can fix the damage just right, you pay more, dig up more, and wait longer for something that could’ve been a same-day job. 

So the right call comes down to the type of pipe, how deep the issue is, where it sits on your property, etc. In this guide, we’ll weigh these factors side by side, along with the cost and lifespan of each fix, to help you decide when you should reline vs. replace your pipes. 

TL;DR

• Choose pipe relining if the existing pipe still holds its shape and has cracks, leaks, root intrusion, corrosion, or minor joint movement, especially when the pipe runs under driveways, concrete, or established landscaping.
• Choose pipe replacement if the pipe has collapsed, severe bellies or misalignment, missing sections, widespread deterioration, an unsuitable route, or needs a larger diameter.
• To choose between the two, get a CCTV drain inspection, compare the full cost and consider the expected lifespan, disruption, and warranty. 

What Is Pipe Relining?

Pipe relining, also known as Cured-in-Place Pipe (CIPP) lining, repairs damaged sewer pipes without digging. Instead of replacing the entire pipe, plumbers repair it from the inside by creating a new pipe within the existing one. 

What Is the Process of Pipe Relining?

1. Inspect the Pipe: The plumber uses a CCTV camera to identify the damage and locate the sections that need repair.
2. Clean and Prepare the Pipe: High-pressure water jetting removes roots, grease, scale, and debris, while the plumber measures the pipe for the correct liner size.
3. Prepare and Install the Liner: The technician cuts a felt or fibreglass liner to size, saturates it with epoxy resin, and inserts it into the pipe through an existing access point, then presses it against the pipe walls.
4. Cure the Liner: The technician cures the resin with UV light, hot water, or steam, forming a strong, seamless inner pipe.
5. Reopen and Inspect the Repair: A robotic cutter reopens the connections where smaller pipes join the main sewer line. A final CCTV inspection then checks the liner and connections before normal sewer use resumes. 

What Types of Pipes Can Be Relined? 

Pipe relining works on almost any drain or sewer pipe, as long as the line still holds its basic shape and has enough structural integrity to support the liner. 

The types of pipes that can be relined include: 

• PVC and Plastic Pipes: Newer homes and renovations commonly use PVC and other plastic pipes. Cracks, damaged joints, and root intrusion can affect these pipes, while relining creates a smooth inner lining to repair the damage.
• Clay and Vitrified Clay (Earthenware) Pipes: Older Queensland properties often have clay or vitrified clay (earthenware) pipes. Ground movement can cause cracks, shifting, and gaps at the joints. Relining seals the damaged sections.
• Cast Iron and Galvanised Steel Pipes: Older properties also have cast iron and galvanised steel vent, waste and drain pipes. Over time, rust, corrosion, and buildup can restrict wastewater flow, but a new liner covers the damaged surface and helps restore flow.
• Concrete and Fibre Cement Pipes: Larger sewer and drainage lines often use concrete pipes, which can crack, corrode, and deteriorate. Relining can repair these pipes without excavation.

What Are the Benefits of Pipe Relining?

• No Major Excavation: Plumbers access the damaged pipe through existing access points, such as sewer inspection openings or access pits, so they can repair it without digging up your yard, driveway, garden beds, or concrete slabs. 
• Fast Installation: Most residential relining jobs take around a day, so you can get your drains/sewer line repaired without weeks of excavation, machinery, and restoration work around your home.
• Lower Overall Costs: Pipe relining costs 30% to 50% less than traditional dig-and-replace methods, as it reduces excavation, soil removal, concrete repairs, landscaping, and other restoration work.
• Long Service Life: A properly installed CIPP liner can last 40 to 60 years, providing a long-term repair for your sewer pipe.
• Less Environmental Impact: Trenchless relining creates less construction waste and disturbs far less soil than excavation. It can also reduce the need for heavy machinery and the materials needed to restore the property afterwards.

What Are The Limitations of Pipe Relining?

• Severely Collapsed or Deformed Pipes: A liner needs the existing pipe to provide a stable path and surface to form against. When a pipe has collapsed, crushed, or lost most of its shape, plumbers replace it.
• Deep Bellies and Grade Problems: A belly occurs when a section of pipe sags and holds wastewater. Because the liner follows the existing pipe’s path, it cannot correct the underlying grade change.
• Sharp Bends and Complex Pipe Layouts: Extreme bends, unusual fittings, and complicated pipe geometry can make liner installation difficult. The liner may wrinkle or fold rather than form a smooth inner surface.
• Reduced Pipe Diameter: The new liner occupies some space within the existing pipe, slightly reducing its internal diameter. This can restrict flow in smaller pipes or systems already operating near capacity.
• Extreme Heat or Chemical Exposure: Wastewater above 60–70°C can soften or weaken the liner, while strong chemicals can cause further damage. Specialised vinyl ester or epoxy resin liners handle these conditions better but can increase repair costs. 
• Poor Installation: Poor cleaning, incomplete curing, or incorrect installation can lead to premature relining failure. Choose a licensed plumbing company, such as 1Touch Plumbing, with experience in drain lining to ensure proper liner installation and reduce the risk of premature failure. 

What Is Pipe Replacement?

Pipe replacement is an invasive repair method that involves excavating the ground, extracting the damaged sewer or stormwater pipe, and installing a new one in its place. Unlike pipe relining, replacement removes the existing pipe rather than repairing it from the inside.

What Is the Process of Pipe Replacement?

1. Inspect and Locate: The plumber uses CCTV and site plans to locate the damaged section and check for underground utilities.
2. Excavate: The crew digs down to expose the damaged pipe.
3. Remove and Replace: They remove the old pipe, prepare the trench, and install a new PVC or HDPE pipe with the correct grade.
4. Test and Backfill: The plumber checks the new pipe for leaks and correct alignment before the crew backfills and compacts the trench.
5. Restore the Surface: The team repairs any concrete, paving, turf, or landscaping affected by the excavation.

What Are the Benefits of Pipe Replacement?

• Provides A Completely New System: Replacement removes severely damaged pipe sections and installs new pipework, so you no longer rely on old pipes affected by corrosion, cracking, scaling, or structural failure.
• Restores Full Flow Capacity: A new pipe keeps its full internal diameter, giving you more flow capacity than a liner, which slightly reduces the existing pipe diameter.
• Fixes Multiple Problems At Once: A replacement can fix collapsed sections, severe bellies, major offsets, and extensive root damage in a single repair, reducing the need for repeated repairs.
• Provides Long-Term Reliability: New PVC and HDPE pipes can last 50 to 100 years, depending on material, installation quality, soil conditions, and application, providing a long-lasting drainage solution.
• More Economical for Accessible Pipes: When a damaged pipe is located under a shallow, open area such as a lawn, simple excavation costs less than the specialised equipment and preparation required for relining. 
• Allows Pipe Rerouting: Replacement allows plumbers to reroute the sewer line when the existing pipe runs under a structure or through an unsuitable area.
• Reduces Recurring Problems: Replacing a severely damaged sewer line resolves ongoing leaks, blockages, and structural issues, resulting in a more reliable sewer system.

What Are the Limitations of Pipe Replacement?

• Significant Surface Disruption: Open-cut replacement requires digging along the pipe’s route, which can mean cutting through your driveways, concrete slabs, gardens, turf, and landscaping.
• Higher Overall Cost: Excavation, equipment, soil removal, disposal, and surface restoration can make replacement more expensive than relining.
• Longer Project Time: A full replacement can take several days, and plumbers may need to shut off water or restrict sewer use during the work, which can temporarily disrupt your daily routine. 
• Risk to Nearby Utilities and Structures: Excavation can disturb nearby water, gas, electrical, and telecommunications services. Digging close to foundations or other structures also requires careful planning to avoid damage.
• More Soil Disturbance and Waste: Excavation requires plumbers to remove and dispose of large amounts of soil, old pipe and other materials. You pay for additional backfilling, surface restoration and disposal. 
• Limited Access Makes Replacement Difficult: Pipes beneath large concrete slabs, buildings, or other hard-to-access areas require extensive excavation or structural work, making replacement impractical or costly.

Key Differences Between Pipe Relining and Pipe Replacement

When Is Pipe Relining the Better Option?

Pipe relining is the best option in the following situations: 

• Cracked or Fractured Pipes That Hold Their Shape: The liner bridges and seals cracks, creating a watertight internal pipe. As long as the existing pipe has not lost its basic circular structure, relining can repair the damage.
• Root Intrusion: After high-pressure jetting clears the roots, the seamless CIPP liner permanently seals cracks and joints where roots entered.
• Offset Joints Under Reactive Clay Soils: Townsville’s reactive clay soils expand and contract between wet and dry seasons, which can cause pipes to shift and joints to open. Relining can cover minor offsets and create a continuous internal wall.
• Corroded or Scaled Pipes: The resin liner creates a new interior surface over the corroded areas and helps restore smoother wastewater flow.
• Cracked or Leaking Pipes: A fully bonded liner seals cracks and joints, helping stop groundwater from leaking into the pipe or sewage from leaking into the surrounding soil.
• Pipes Under Driveways, Concrete Slabs, or Landscaping: Relining lets plumbers repair pipes without digging up driveways, concrete, gardens, or established landscaping. It can also help protect trees and other features around heritage or character homes. 
• Minimal Disruption and Fast Turnaround: Most residential relining jobs can be completed in about 1 day. You can stay home during the work, although your plumber may ask you to limit sewer use while the liner is installed and cured.
• Cost Savings: Relining can cost $2,000–$3,000 less than pipe replacement. If you have a tight budget and the existing pipe is suitable for relining, it can be the more affordable option. 

When Is Pipe Replacement the Better Option?

Pipe replacement becomes the necessary choice in the following situations:

• Completely Collapsed or Missing Pipe Sections: If the pipe has caved in or sections are missing entirely, there is no stable host pipe for a liner to follow or bond against; then full replacement is the only option.
• Outdated or Hazardous Materials: Older properties may have galvanised steel, polybutylene, or lead pipes. When these materials deteriorate across multiple sections, replacing them is best, as it removes the need for repeated patch repairs.
• Severe Bellies and Grade Failures: Replacement can correct deep bellies by removing the sagging section, re-grading the trench, and installing the new pipe at the correct slope.
• Widespread Leaks and Rust: When leaks keep appearing in different sections or older metal pipes show extensive corrosion, replacing the affected pipework can provide a more reliable long-term repair.
• Major Offsets and Misalignment: Townsville’s reactive clay soils shift pipes and joints, sometimes causing severe misalignment that relining can’t correct. Replacement realigns the pipe correctly.
• Pipes That Need Rerouting or Design Correction: A sewer line may run beneath a structure, follow an unsuitable route, or have the wrong grade. Replacement allows the plumber to change the route and correct the design.
• Already Excavating For Major Site Work: If you are already demolishing or rebuilding a yard, parking area, driveway, or concrete slab, replacing the pipe at the same time can reduce the cost of accessing the line.
• Major Home Renovations: Adding bathrooms or changing room layouts requires a new drainage configuration. Replacing and reconfiguring the pipework makes more sense than keeping old lines that no longer suit the property’s layout.

Final Thoughts: How to Know Which Pipe Repair Option Is Best For You

You now know what signs point to relining and what point to replacement. But knowing the signs isn’t the same as knowing which ones are actually true for your pipe. And you can’t settle that from looking at the surface only. 

That’s why, at 1Touch Plumbing, we start every sewer/drain repair job with a CCTV inspection to locate the damage. Then use high-pressure hydro jetting to clear roots, scale, and debris so the pipe’s condition is fully exposed. From there we tell you whether pipe relining or replacement will make most sense for you. 

Contact us today for honest advice on your sewer/drain pipe repair.

FAQs

Can a collapsed pipe be relined?

No. Relining requires the existing pipe to maintain its shape so the liner can bond to the host pipe during curing. A fully collapsed or missing section leaves no pathway for the liner to pass through and no support for it.

Can tree roots grow through a relined pipe?

No. A seamless CIPP liner has no joints for roots to enter. It also seals cracks and gaps that allowed roots to enter the original pipe.

Can you use your plumbing during pipe relining?

No. You cannot use the affected plumbing during active installation and curing, which typically takes 3–6 hours. You may also need to heavily limit water use for 24–72 hours after installation. Your plumber will tell you when you can safely resume normal use.

Will insurance cover pipe replacement?

Generally, standard home insurance does not cover the cost of replacing the pipe itself. However, your policy may cover resulting water damage when the pipe breaks suddenly and accidentally. Check your policy and speak with your insurer before committing to the repair.