Subducting: Maximising the Infrastructure You Already Have
Expanding fibre capacity is a growing challenge for network operators. Installing new duct routes is often expensive, disruptive and in many locations simply not realistic. Urban streets, commercial estates and live business parks come with restrictions that make civils work difficult to justify.
Subducting provides a practical way forward. By installing new microduct pathways inside existing ducts, operators can increase capacity, add resilience and plan for future growth without disturbing the infrastructure that is already in use.
What Is Subducting?
Subducting is the process of installing smaller microducts inside a larger host duct. These new inner pathways can then be used to blow or pull fibre when required.
The concept is straightforward. You create additional capacity without excavating and without interfering with the active fibres already running through the duct.
Subducting delivers:
- New fibre pathways inside existing ducts
- A modular, scalable approach to future expansion
- A safe method for increasing capacity without interrupting live services
It is a clean, strategic upgrade that prepares networks for long-term growth.
Why Use Subducting?
Subducting is chosen for three core reasons: cost efficiency, flexibility and minimal disruption.
Reuses existing infrastructure
There is no need to dig or install new ducts. You maximise what is already in the ground.
Reduces installation costs
Avoiding civils work provides immediate savings in both labour and reinstatement.
Supports phased upgrades
Microducts can remain unused until increased capacity is required. Fibre can then be blown in without further groundworks.
Protects live services
Existing fibres stay undisturbed throughout the installation. Service continuity is maintained from start to finish.
Improves long-term scalability
Subducting creates a structure that can expand as demand grows, rather than forcing major upgrades every cycle.
Where Subducting Makes the Most Sense
Subducting is particularly effective in locations where access or disruption must be controlled.
Urban deployments
High civils costs and limited access make reuse of existing ducts a major advantage.
Commercial and business parks
Ideal for upgrading tenant connectivity without interrupting daily operations.
Phased or modular network growth
Perfect for rollouts where capacity may need to increase year by year.
Clients looking for stronger ROI
Reusing existing ducts provides both financial and operational value.
The Right Tools for Effective Subduct Installation
Accurate subduct installation relies on controlled pushing or blowing forces and reliable handling of multiple microducts. This is where the right fibre blowing machinery makes a clear difference.
The Flowlight V3 Fibre Blowing Machine is well suited to subducting when paired with the appropriate accessories. With the dedicated subducting kit, the V3 can install:
- 7 x 7/3.5 mm microducts
- 4 x 14/10 mm microducts
This gives installers the flexibility needed to deliver clean, secure and consistent subduct routes that are ready for future fibre installation.
More information on the V3 machine is available here.
Why Subducting Matters for Modern Networks
Demand for bandwidth continues to rise and operators need ways to scale without repeated groundworks. Subducting provides a practical method for building networks that are easier to expand, maintain and upgrade.
It allows installers and network owners to:
- Prepare for future capacity
- Avoid unnecessary excavations
- Deploy upgrades quickly
- Improve the value of existing assets
- Reduce service disruption during works
When combined with the right fibre blowing equipment, subducting becomes one of the most effective ways to future-proof modern fibre networks.
