Ageing pipeline networks present constant challenges; ground movement, corrosion, and deformation can all compromise structural integrity. For engineers responsible for maintaining essential water and wastewater systems, the goal is to find a solution that restores performance while minimising disruption and environmental impact.
That’s where iPlus® Composite comes in. Developed through decades of trenchless rehabilitation expertise, it combines fibre-reinforced composite engineering with Insituform’s proven CIPP technology to create a liner that achieves higher stiffness, durability, and efficiency during installation.
What Makes iPlus® Composite the Best Choice for Stronger Pipe Repairs?
Conventional CIPP relies on resin-saturated felt liners, which provide reliable rehabilitation for circular pipes but have limitations in more complex shapes. iPlus® Composite integrates reinforcing fibres within the laminate structure to deliver a significant increase in flexural modulus and structural stiffness.
This additional reinforcement forms a composite sandwich layer that distributes load more evenly through the wall section. As a result, it can withstand higher ground and live load stresses, even in non-circular profiles such as egg-shaped and flat-bottom arch pipes.
Engineers value this because it enables a truly structural repair, not just a flow liner. It performs under full deteriorated conditions, restoring the host pipe’s mechanical integrity without excavation. The result is a stronger, longer-lasting rehabilitation solution that meets design standards across a range of soil and hydraulic conditions.
How Does iPlus® Composite Improve Flow Capacity in Pipe Rehabilitation?
A key performance issue in many rehabilitation projects is loss of internal diameter after lining. Thicker liners reduce the effective flow area, particularly in gravity pipelines.
Because of its composite structure, iPlus® Composite achieves the required stiffness and strength with roughly half the wall thickness of traditional rehabilitation. This means internal diameters can be largely maintained while still meeting all structural criteria.
In practical terms, flow hydraulics are preserved, or in many cases improved, as smoother internal surfaces and thinner walls reduce friction losses. For water authorities and contractors, this translates to consistent flow performance without needing upsizing or additional treatment capacity.
This efficiency also simplifies design calculations and helps achieve compliance with flow and velocity requirements under UK water and wastewater infrastructure standards.
How Does iPlus® Composite Benefit the Environment During Installation?
Reducing environmental impact is now central to engineering project delivery. iPlus® Composite supports this through both its material design and installation process.
- Less resin is required, lowering embodied carbon and overall material demand.
- Shorter curing times reduce site energy consumption and equipment runtime.
- Reduced product weight means lower transport of fuel use and fewer emissions.
- Trenchless installation minimises surface disturbance, reinstatement work, and disruption to local communities.
Collectively, these factors contribute to measurable reductions in carbon emissions across the full project lifecycle. For organisations working toward environmental performance targets or sustainability certification, iPlus® Composite provides a practical way to achieve both operational and ecological objectives.
What Types of Pipes and Projects Can Benefit from iPlus® Composite?
iPlus® Composite was designed for versatility across a broad range of structural rehabilitation scenarios. iPlus® Composite has a few benefits, it performs effectively in:
- Medium to large diameter gravity pipelines from 600 mm up to 2 400 mm
- Fully deteriorated pipes, including those with offset joints or deformation
- Complex geometries, such as ovoid, egg-shaped and flat-bottom arches
- All standard host materials, including concrete, brick, and clay
This adaptability makes it a preferred option for utilities, councils, and engineering contractors delivering rehabilitation works in constrained environments. It maintains flow, restores strength, and minimises overall installation time, key factors in reducing total project cost and risk.
Why iPlus® Composite Is the Stronger, More Efficient Choice for Structural Pipe Repairs
For engineers, project managers, and infrastructure specialists, the value of iPlus® Composite lies in its technical reliability and installation efficiency. It delivers the mechanical performance of a fully structural liner with the environmental and operational advantages that modern projects demand.
The fibre-reinforced laminate design provides superior load-bearing capability while maintaining thinner walls, enabling high performance even in non-circular or variable-condition pipes. Installation is faster, curing requires less energy, and long-term durability reduces maintenance demands.
In short, it is a proven, engineered system that extends asset life while aligning with environmental and operational priorities.
If you’re assessing rehabilitation options or designing a specification for a complex pipeline project, contact Insituform to discuss how iPlus® Composite can meet your structural and performance requirements.
Talk to our technical team today to evaluate your network conditions and find out how iPlus® Composite can strengthen your next pipeline rehabilitation project.
