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Glossary

Componentisation

The breaking of an asset into parts that are recognised, valued and depreciated separately, because they have different useful lives.

Under accrual accounting an asset with parts that wear out at different rates is not depreciated as one item. A building envelope, its mechanical plant and its fit-out have different lives, and componentisation is what allows each to be written down over its own.

It becomes acute during a conversion from cash to accrual accounting, because the componentisation decided at that point fixes how the estate appears on the balance sheet for decades.

The same term, through four lenses

01

Project

the delivery team and the contract

The project does not componentise. It accumulates cost against whatever structure its cost breakdown uses, which is usually the contract, the package or the trade, because that is what payment certificates are issued against.

This is the decisive fact and it is nobody’s decision. The breakdown that finance will need at handover has to be derivable from records the project kept for a different reason, and no clause requires the two to correspond. A project that captured cost by contract cannot produce a component split afterwards; the information was never collected.

Fixed by

FIDIC Conditions of Contract, 2017 edition: the bill of quantities and the schedules against which interim payment is certified. Nothing in the payment clauses requires cost to be captured by asset or by component.

Recorded in

The cost breakdown structure, and the interim payment certificates.

02

Engineering

design, commissioning and the technical record

Engineering breaks an asset down into what can be located, isolated, maintained and replaced. The unit is the thing a technician is dispatched to: this air handling unit, that valve, that run of duct.

The breakdown descends from the design and the commissioning record, and its depth is set by maintainability rather than by value. A cheap component on a critical system is worth identifying separately; an expensive one that is never touched independently is not.

Fixed by

ISO 55001:2024, Clause 7.6, data and information. The technical breakdown is also what the operation and maintenance manuals and the as-built records are organised around.

Recorded in

The maintenance management system’s asset hierarchy, and the O&M manuals.

03

Finance

the accounts and the fixed asset register

Finance componentises for depreciation. IPSAS 45 paragraph 41 requires each part of an item with a cost or value significant in relation to the total to be depreciated separately, and paragraph 43 requires the remainder, the parts individually not significant, to be depreciated too. The standard’s own examples are the substructure and the surface of a road, and the airframe and engines of an aircraft.

Two things follow that engineers rarely expect. Significance is measured in money, not in criticality, so the test is what a part costs relative to the whole. And paragraph 42 permits parts with the same useful life and depreciation method to be grouped, so finance may deliberately merge components engineering keeps apart.

Fixed by

IPSAS 45, Property, Plant, and Equipment, paragraphs 41 to 44 on depreciating parts separately, with application guidance at AG24.

Read the sources

Recorded in

The fixed asset register, at the level the accounts must defend.

04

Operations

the people who run and maintain it

Operations inherits both breakdowns and has to work the one that answers the question in front of it: what failed, what is it costing to keep running, and is it due for renewal.

The renewal question is where the two collide. The decision to replace is taken on condition and criticality, which live in the technical register, and it is funded against a carrying value and a remaining life, which live in the financial one. An operator with no traceability between them can say a chiller is failing, or that a chiller has book value left, but cannot put the two sentences in the same paper.

Fixed by

ISO 55001:2024, Clause 7.6, data and information, and ISO/TS 55010 on aligning the financial and non-financial functions.

Read the sources

  • ISO 55001:2024, asset management system requirements2024 edition; read 2026-09-26.ISO’s product page: the publication details and ISO’s own summary of the standard, not the requirement text. The contents, foreword and introduction cited in this publication are taken from the standard’s preview pages hosted on the ANSI webstore, not from this page.

Recorded in

The renewal plan, and whatever reconciliation exists between the two registers.

Where the lenses part

  • Finance against Engineering

    Significance is the whole disagreement. Finance splits by value, because that is what IPSAS 45 paragraph 41 asks for, and may group parts with the same life under paragraph 42. Engineering splits by what can be isolated and replaced. A control system that is 2% of the capital cost and stops the building when it fails is one line to finance and forty to engineering. Neither is wrong: they are answering different questions, and nothing in either standard obliges the answers to correspond.

  • Project against Finance

    The project captures cost against contracts and packages; finance needs it against assets and components. The translation is only possible if somebody required it while the cost was being incurred, and no standard contract does. This is why the gap is structural rather than a failure of diligence: at the moment the requirement becomes visible, at handover, the records that could have satisfied it are closed.

What has to agree, and how you would know

The datumHeld byThe test
The component list itselfEngineering, FinanceTake ten components from the maintenance hierarchy and ask which financial asset line each falls under. Then take the ten largest financial components and ask which maintainable items they contain. If either direction cannot be answered from records, the two registers are not traceable to each other.
Cost against each componentProject, FinanceTake one component from the register and trace its cost back to the payment certificates it came from. If the answer is an apportionment made after handover, record that: the figure is an estimate, and it is the basis of a depreciation charge that will run for decades.
The life assigned to each componentFinance, OperationsCompare the useful life in the fixed asset register against the replacement interval in the renewal plan, component by component. Where they differ, one of the two documents is wrong about the same physical thing, and IPSAS 45 paragraph 48 requires the financial one to be reviewed annually anyway.

Sources

IPSAS 33, first-time adoption of accrual basis IPSAS. ISO 55001:2024, Clause 7.6, data and information. ISO/TS 55010 on the alignment of financial and non-financial functions.

Read the sources