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When your underground pipes are damaged, you have two main options: dig them up and replace them, or reline them from the inside without excavation. Here's how to decide which approach is right for your situation.
What Is Pipe Relining?
Pipe relining is a trenchless repair method that creates a new pipe inside your existing damaged pipe. A flexible liner coated with epoxy resin is inserted into the pipe and inflated against the pipe walls. Once the resin cures (hardens), you have a smooth, jointless pipe-within-a-pipe that's structurally sound and resistant to root intrusion.
The process is done through existing access points such as manholes, cleanouts, or small excavation pits — eliminating the need to dig up your entire yard, driveway, or landscaping.
What Is Traditional Pipe Replacement?
Traditional pipe replacement involves excavating the ground above the damaged pipe, removing the old pipe, and installing a new one in its place. This has been the standard repair method for decades and is still the right choice in certain situations.
Comparing the Two Methods
Cost: Pipe relining typically costs 20-40% less than full replacement when you factor in excavation, reinstatement of surfaces (concrete, pavers, landscaping), and the time involved. However, relining costs more per metre than the pipe itself — the savings come from avoiding excavation.
Disruption: This is where relining really shines. A reline job can often be completed in a single day with minimal disruption to your property. Traditional replacement can take several days and requires digging trenches across your yard, potentially destroying gardens, driveways, paths, and fences.
Lifespan: Quality pipe relining products come with a 50-year warranty. New PVC pipes also have a 50+ year expected lifespan. Both methods deliver a long-term solution.
Pipe condition: Relining works best when the existing pipe has maintained its basic shape. If the pipe has completely collapsed, been crushed, or has significant bellies (sagging sections), replacement may be the only option.
When Relining Is the Best Choice
- Pipes are cracked, have joint displacement, or suffer from root intrusion but still maintain their shape
- The pipe runs under structures (driveways, buildings, pool areas) where excavation would be extremely expensive or impractical
- You want to preserve established gardens, mature trees, and landscaping
- You need a fast repair with minimal downtime
- The pipe diameter is between 50mm and 300mm (most residential and light commercial pipes)
When Replacement Is Necessary
- The pipe has completely collapsed and lost its shape
- There are significant changes in pipe grade (bellies) that need to be corrected
- The pipe is undersized and needs to be upgraded to a larger diameter
- The pipe alignment needs to be changed (rerouted)
- The pipe is made of materials that are incompatible with relining (rare, but possible)
The CCTV Inspection Step
Before recommending either approach, we always perform a CCTV drain inspection. This gives us a clear picture of the pipe's condition, the location and severity of damage, and any factors that might affect the repair method. We'll show you the footage and explain your options so you can make an informed decision.
Contact Precision Plumbing Co for a CCTV drain inspection and obligation-free quote on pipe relining or replacement.
