Blocked or broken pipes can lead to expensive property damage if not handled properly. Many assume the only fix is full pipe replacement, which often means excavation and high restoration costs. But for pipes that are cracked or leaking but still structurally intact, another option may be more practical.
Pipe relining is a trenchless method that repairs pipes from the inside, avoiding the need to dig up lawns, driveways, or concrete. It can reduce time on site and limit extra costs for reinstating hard surfaces. This makes it a useful alternative in areas where access is difficult or disruption needs to be minimal.
Understanding when each method is suitable helps avoid unnecessary costs and delays. In this guide, we compare the cost factors, disruptions, and practical applications of pipe relining and full pipe replacement, with a focus on which option delivers better value for Australian homes and businesses.
What is Pipe Relining?
Pipe relining is a trenchless method for repairing cracked, leaking, or root-damaged pipes without excavation. It starts with a CCTV inspection to assess the damage. After the pipe is cleared using high-pressure jetting, a resin-soaked liner is inserted, inflated, and cured in place. This creates a new internal pipe that seals faults and restores flow.
The process suits pipes made of clay, PVC, or cast iron, as long as they are still structurally sound. It’s often used under driveways, concrete slabs, or landscaped areas where digging would increase time and cost.
Once cured, the new pipe has a smooth surface that resists corrosion and blocks future root intrusion. This method helps extend the life of damaged pipes without removing or replacing them. Our pipe relining service is used in residential and commercial settings where quick, low-disruption repairs are needed.
What is Full Pipe Replacement?
Full pipe replacement involves removing and replacing damaged or outdated sections of pipe. This usually requires excavation to access the pipe, which may include digging through lawns, driveways, or concrete slabs depending on the pipe’s location. Once exposed, the old pipe is removed and a new one is installed in its place.
This method is often used when a pipe has collapsed, is severely deformed, or cannot be repaired using relining. Replacement is also recommended when the entire system is outdated or undersized for current water usage and flow requirements.
The process can take several days or even weeks, especially if access is limited or restoration works are extensive. It often involves additional costs for concrete cutting, machinery hire, and reinstating the site once the new pipe is laid.
Although pipe replacement provides a new system with full flow capacity, the disruption and higher labour cost make it a more suitable option only when trenchless repair isn’t feasible.
The Cost Breakdown
The total cost of pipe repair depends on location, depth, material, and access. While pipe relining may appear more expensive per metre, it often reduces or avoids other costs tied to excavation, restoration, and labour.
Pipe Relining Costs
- Estimated per metre: $400–$1,000
- No digging required
- No surface restoration needed
- Shorter project time (1–2 days)
Although the upfront cost per metre is higher, relining eliminates the need to break and restore surfaces. This makes it a more economical option when pipes run under concrete, buildings, or landscaping.
Pipe Replacement Costs
- Estimated per metre: $250–$350
- Excavation required in most cases
- Restoration of concrete, paving, or garden areas adds to cost
- Project duration may extend to days or weeks
The lower material cost per metre in replacement is often outweighed by the added work and site reinstatement. In areas with difficult access or where restoration is extensive, replacement can become significantly more expensive overall.
Other Factors to Consider
When comparing pipe relining and full replacement, the cost is only one part of the decision. Several practical factors influence which method is more appropriate for the situation.
- Lifespan
Both relining and replacement offer long-term results. A well-installed relined pipe can last 25 to 50 years. Replacement pipes, especially PVC, also provide durability over several decades. - Disruption
Relining causes minimal disruption because it doesn’t involve digging. This is beneficial for homes, businesses, and strata properties where access is limited or where surfaces like driveways or tiling need to stay intact. - Site Conditions
Relining requires the existing pipe to maintain its shape. If a pipe is crushed, collapsed, or severely misaligned, full replacement may be the only option. - Property Use
For properties in use during the repair, relining allows for faster completion with fewer interruptions. In contrast, replacement may require temporary access restrictions and longer timeframes.
Each situation needs to be assessed based on damage extent, pipe condition, and location. The more invasive method is not always the most effective.
When Relining Makes More Sense
Pipe relining is often the more practical option when the existing pipe structure is still intact and the goal is to minimise surface damage and repair time. It is well suited to situations where access is difficult or where property owners want to avoid excavation-related costs.
Relining is typically recommended when:
- Pipes run beneath concrete slabs, driveways, or landscaped areas
- The damage is limited to cracks, corrosion, or root intrusion
- There’s no full collapse or severe deformation
- Quick turnaround is preferred without major site disruption
This method also avoids issues with surface reinstatement. For properties with tiled floors, decorative paving, or other permanent finishes, removing and restoring these features can add significantly to total project cost during full replacement.
In commercial and strata properties, relining can often be completed without shutting down water services for extended periods. It also supports compliance with modern standards for internal pipe repairs in heritage-listed or space-constrained sites.
When pipe access is available and the damage is not structural failure, relining is usually a lower-risk, lower-disruption solution.
Image cue: [Technician feeding liner into pipe below a concrete footpath]
When Replacement is Better
Pipe replacement is the preferred option when the existing system is no longer structurally viable. If a pipe has collapsed, is significantly deformed, or has shifted out of alignment, relining is not possible. Replacement allows full access to remove the damaged section and install new pipework that meets current standards.
Situations that require full replacement include:
- The pipe has fully collapsed or is crushed
- Severe misalignment prevents liner insertion
- The existing system is outdated, undersized, or made of unsuitable materials
- Major renovations already involve excavation work
In some cases, a combination of partial replacement and relining may be used. For example, if only one section is too damaged to reline, that portion can be replaced while other sections are relined.
While more disruptive and time-consuming, full replacement ensures flow capacity, proper slope, and long-term system reliability. It also provides the opportunity to upgrade materials and improve access for future maintenance.
Planning replacement early helps avoid future issues, especially in ageing systems where multiple sections are failing.
Not Sure Which Option to Choose?
Choosing between pipe relining and full replacement depends on the condition of the pipe and where it’s located. Both methods are long-term solutions, but one may offer clear cost and access advantages depending on the job.
If the pipe is still structurally sound but showing signs of leaks, cracks, or root entry, relining can resolve the issue with less disruption. It’s especially suitable in areas where digging would disturb concrete, tiling, or established landscaping. The process is faster, and there’s no need to restore the surface afterward.
In contrast, if a pipe has collapsed, is severely misaligned, or the entire system is deteriorating, replacement is the safer option. It provides full access and allows for complete renewal of the line, including upgrading to modern materials if needed.
A CCTV pipe inspection is the most reliable way to determine which option applies. This allows plumbers to assess internal conditions accurately before any work begins.
Book a Professional Inspection
Pipe damage is not always visible from the surface, and guessing the extent of the issue can lead to unnecessary costs. A CCTV inspection is the best way to confirm whether pipe relining or full replacement is suitable for the problem.
At Green Planet Plumbing, we provide both services and assess each situation based on structural condition, location, and access. Our licensed plumbers carry out detailed inspections before recommending the most cost-effective and long-term solution.
If you’re dealing with blocked, leaking, or ageing pipes, contact us to arrange an on-site assessment.