Total cost of ownership of a coating: ROI calculation

Why per-litre price misleads

Comparing coatings only on per-litre price omits labour, surface preparation, access, production downtime and inspection. A useful analysis compares documented scenarios over the same period and with the same operating assumptions.

The 5 components of total cost

The total cost of ownership (TCO) of a coating system over its service life breaks down into:

• Material: coating, solvents and consumables

• Application labour: preparation, application and supervision

• Access and surface preparation: blasting, scaffolding and containment

• Production downtime: site-specific value of unavailability

• Inspection and maintenance: planned work and failure scenarios

Example method over 20 years

For a storage tank, calculate each option's initial installed cost, downtime, inspection and expected interventions. Include at least an optimistic, central and adverse scenario for time to maintenance. Discount future cash flows when the horizon warrants it. This sensitivity analysis identifies which assumptions drive the decision without inventing a universal price or lifespan.

The hidden cost of downtime

The often-underestimated line item is production downtime cost. The asset owner should provide or validate it because it depends on the process, inventory, workarounds and outage timing. Do not count an outage as avoided if it would have occurred for other maintenance.

Conclusion

Total cost of ownership helps compare systems when assumptions are explicit and consistent. No system is always the least expensive: the best option depends on exposure, service period, outage constraints, application quality and uncertainty in the analysis.