S
SLIPROX
Green composite sleepers
Lifecycle calculator

Composite sleeper business case

Savings from skipping one replacement cycle.

A buyer should not compare sleeper price alone. The expensive part is often the intervention around the sleeper: crew, machines, track access, logistics, disruption and disposal. Doubling service life can postpone one full intervention and reduce lifetime cost.

25 yrsWooden sleeper cycle
50 yrsComposite sleeper cycle
€200Non-sleeper work per change

What this calculator shows

Lifecycle cost, NPV and break-even price.

Enter your assumptions for sleeper price, non-sleeper replacement cost, lifetime, track length and discount rate. The calculator compares wooden sleepers against composite sleepers over the chosen analysis period.

Core sales logic
Pay a slightly higher unit price now, avoid a full replacement cycle later.

Inputs

Defaults are set to the current discussion: €75 wood sleeper, €90 composite sleeper, €200 non-sleeper replacement work, 25 vs 50 years.

Track section
Costs
Service life & finance
Wood-specific extra costs
Operational impact: track closures can also create lost capacity and lost revenue, because trains cannot run while the work is being carried out. These site-specific costs are not included in the calculator, but fewer replacement cycles can reduce both maintenance cost and traffic disruption.

Results

Calculated instantly from your assumptions. NPV discounts future avoided replacement cycles.

What NPV means: NPV = net present value. It converts future costs into today’s money using the discount rate. This matters because avoiding a replacement in 25 years is valuable, but it is worth less today than avoiding the same cost immediately.
Undiscounted lifecycle saving — — per km
NPV lifecycle saving — — per km
Total sleepers—in selected track section
Wood all-in replacement—per sleeper event
Composite all-in replacement—per sleeper event
Break-even composite price—sleeper-only, NPV basis

Cost comparison

Wood
—
Composite
—
Saving
—
ScenarioNominal costNPV costCost / sleeper NPV
Wooden sleepers———
Composite sleepers———
Saving with composite———
—
How the calculation works

The model calculates replacement costs at year 0, then every service-life interval until the end of the analysis period. With the default 50-year period, wooden sleepers are replaced at the start and once again after 25 years, while composite sleepers are replaced only at the start. NPV means net present value: future costs are discounted back to today using the selected discount rate. The break-even price is the maximum sleeper-only composite price that makes the NPV equal to the wood scenario. Track closures can also create lost capacity and lost revenue, because trains cannot run while the work is being carried out. These site-specific costs are not included in the calculator, but fewer replacement cycles can reduce both maintenance cost and traffic disruption.