ASMM, the Civil Engineering SMM, the TMR Schedule of Rates and RICS NRM all exist for one reason: so that two people handed the same drawing arrive at the same quantity. Inside an estimate, the thing that does the equivalent job is a code set.
A method of measurement is a published rule book that fixes how a quantity is derived from a drawing — what is measured, in what unit, described with what content, and with what deemed to be included in the rate that follows. It is not a pricing manual, and it will never tell you what anything costs. It settles the narrower and more important question of what a line item is, so that the price attached to that line means the same thing to the person who wrote it and the person who evaluates it.
The reason this matters is commercial rather than academic. Hand the same structural drawings to two experienced estimators and you get back two different tonnages of reinforcement, because one measured chairs, spacers, tie wire and lapping and the other assumed those were deemed included. Both readings are defensible. Only one can be in the contract, and the method of measurement decides which.
Where no method is named, the bill still gets priced — it just stops being comparable. The spread between submissions ends up reflecting how each tenderer read the scope rather than how efficiently each can build it, and the evaluation panel normalises the returns by hand, under time pressure, with no audit trail. That undocumented normalisation is the most common root of a post-award argument about what the rate was supposed to cover.
TX1:Trinity keeps parallel code sets — delivery WBS, AS 2124 schedule, client chart of accounts — over the same priced item, with percentage-split allocations instead of a second round of measurement.
Start a free 14-day trialA method of measurement is therefore the first of two vocabularies every estimate needs. The first governs quantities and comes from outside your organisation, published and enforceable. The second governs where a priced quantity reports — which work package, which schedule item, which cost centre — and almost nobody publishes that one.
Strip away the tables and worked examples and every method does the same three jobs. The unit is the one everybody remembers. The other two are where the money is.
What constitutes one item and where the next one begins. Is a trench one item or four — excavate, bed, lay, backfill? Is a pit measured as an assembly or as its parts? The boundary decides how coarse your estimate can be before it stops being defensible.
m, m², m³, kg, t or No., and with it the measuring convention: net or gross, over openings or around them, to the neat line or to the pay line, rounded up to the next whole unit or carried to two decimals.
The deemed-to-include list — the clause saying the tonne rate carries its own lapping, or the cubic metre of excavation its own dewatering. It generates more tender qualifications and variation claims than the other two combined.
The coverage rule is the bridge between measurement and costing, which is why the standard is worth reading before you price anything. When the specification says an item is deemed to include setting out, temporary support, testing and rectification, it has handed you a checklist of operations that must appear somewhere in the build-up. Each is either priced, deliberately gated to zero with a reason recorded, or deferred to an item the specification expressly authorises. A build-up that silently drops one is not cheap; it is wrong in the same direction every time, which is how a library of quietly under-scoped rates comes into existence.
What no method fixes is the rate itself. Measurement tells you the tonne of reinforcement includes its own tie wire; it says nothing about crew size, crane hours, waiting time or wastage. Measurement defines the question and a first-principles build-up answers it. Confusing the two — treating a published schedule of rates as though it were also a published set of prices — is how organisations end up carrying rates they cannot explain.
Australian practice runs on four measurement frameworks. They are dialects rather than competitors, each fitted to a procurement context, and most estimators working across sectors will use at least three.
| Framework | Published by · domain | Where you meet it |
|---|---|---|
| ASMM | AIQS · building work, organised by traditional element | State government building procurement, health and education projects, large commercial and fitout work |
| Civil Engineering SMM | Civil engineering · infrastructure work | Earthworks, drainage, pavements, structures and utilities for water authorities, energy networks and local government |
| TMR Schedule of Rates | Queensland TMR · aligned to the MRTS specifications | Queensland road and transport delivery, priced directly by panel and stand-alone contractors |
| RICS NRM 1–3 | RICS · international | Internationally funded resources, energy and major PPP work where the funder specifies NRM measurement |
The ASMM is structured the way a building is structured — substructure, superstructure, finishes, services, external works — which is why an elemental cost analysis drops out of an ASMM bill almost for free, and why the same bill is awkward to reconcile against a programme organised by zone and level. The Civil Engineering SMM trades that elemental logic for an operational one: its items follow the work as performed, which suits linear infrastructure where the same operation repeats along a chainage.
The TMR Schedule of Rates is the unusual one, because it is simultaneously a measurement convention and a payment schedule. The measurement basis and the basis of payment are read together out of the governing MRTS clause — drainage, pavement, structures, traffic and electrical each carry their own rules, standard drawings and mandatory testing. That coupling is a genuine advantage: measure the item correctly and you have also established what triggers payment and what the rate is deemed to cover, in one reading.
The RICS NRM suite splits the job across three documents — order-of-cost estimating and cost planning, detailed measurement, and maintenance works — so a project can stay inside one family of rules from business case through to whole-of-life. Australian projects meet NRM when the money comes from offshore and the funder brings its own reporting expectations with it.
The one sentence: a method of measurement is a shared vocabulary for quantities, and a code set is a shared vocabulary for where those quantities report — an estimate that has the first without the second gets re-typed by hand at every reporting cycle.
Take a single bored pile. To the delivery team it is an activity inside a work package, sitting under a structure, under a site, in the work breakdown structure that drives the programme. To the contract administrator it is a schedule item under AS 2124, with a measurement basis and a payment trigger. To the client's finance group it is a row in a chart of accounts that was designed years before the project existed and will outlive it. To the cost planner it is part of an element. To the sustainability reporter it is a boundary around embodied carbon. Five audiences, five structures, one pile.
The usual response is one of two bad options. Either the item is measured more than once, in parallel workbooks maintained by different people, which guarantees they drift apart by the second revision. Or one structure is nominated as master and everything else is hand-mapped at each cut-off, which works until the month the mapping is done in a hurry and the totals stop tying out. Both treat a reporting problem as though it were a measurement problem.
The alternative is to separate the two vocabularies properly: measure once, price once, classify many. A code set is a classification tree that sits over the priced item rather than inside it — a published structure everyone agrees to use, exactly as a method of measurement is. Multiple code sets coexist over one estimate because they are not competing for the same field. And because some items honestly do not belong to a single branch — site establishment is not 100% of anything, a shared crane serves four structures at once — allocations are percentage splits, not assignments. The cost is distributed rather than duplicated, so every tree still sums to the same project total.
The method is never stated. The bill is issued, the quantities look professional, and nowhere in the front matter does it say which rule book generated them. Every downstream disagreement about coverage then becomes a matter of opinion. Naming the method — and the edition — on the first page of the bill costs one line and removes an entire category of dispute.
One flat code tree is asked to serve every audience. An organisation adopts a single cost-code structure, usually the one finance prefers, then bends it to also carry the WBS and the schedule. The result is a code six segments long that nobody can read and that still fails at least one audience. Parallel trees solve the problem a compound code was invented to work around.
Items get split to satisfy a report. Somebody needs the pile cap reported separately from the pile, so the item is cut in two. Now there are two half-items, each with a build-up too thin to defend, neither comparable to anything in the rate library. The report was worth having; the split was not the way to get it.
Methods are mixed inside one bill. The structures package is measured to one convention and the drainage package to another, because two people prepared them. Each package is internally coherent; the bill as a whole is not. It surfaces during tender clarification, when the two are finally compared against each other.
Provisional work is measured as though it were firm. Provisional quantities and sums sit in the same columns as measured work, unflagged, then enter benchmarks and unit-rate comparisons as if they had been priced from drawings. They are placeholders with an at-risk quantity attached, and treating them otherwise quietly corrupts the historical record you will later want as a reference class.
A sixth failure is less a mistake than an accepted cost: the monthly re-map. Somebody rebuilds the mapping between the estimate structure and the client's reporting structure every cycle. Nobody counts those days, because they have always been spent. They are the price an organisation pays for having only one classification field.
TX1:Trinity treats classification as a set of parallel trees rather than a code field on each item. Each code set is its own hierarchy — a delivery work breakdown structure, an AS 2124 schedule, a client chart of accounts, an elemental breakdown — and a priced item can be allocated across every set at once, with percentage splits where the honest answer is that it belongs partly to each. The item is measured once and built up once; the reporting structures are applied afterwards and can be added, changed or retired without touching the build-up underneath.
Because allocation is a split rather than a copy, the arithmetic reconciles by construction: each code set sums to the same project total, so the WBS report, the schedule report and the finance report agree without anyone reconciling them. Distributed costs return to the unit rate through CalculatedSellRate = DirectRate + (TotalAllocated / Qty), so an allocated preliminary or a shared crane shows up in the rate for the item that carried it, not in a separate column that gets forgotten.
The same discipline runs downwards into the resources. Built-up resources recompute as the sum of their contributing component rows, so changing one component cascades to the package rate, to every item using it, and through to all allocations — which is why a library authored once and imported as a package stays usable across clients with quite different chart-of-accounts conventions, a point taken up in building a library. Carbon rides the same objects: emissions attach to the resources you already priced, so the Scope 1, 2 and 3 view inherits the code sets rather than needing its own.
A second-order benefit only shows up after a few jobs. When every estimate an organisation produces is coded consistently, the estimates become queryable as a set — and a consistently coded back catalogue is the raw material that turns your own delivered work into a benchmark, the argument made in full on optimism bias and the outside view.
The ASMM is the AIQS rule book for measuring building work in Australia. It sets the boundary of each item, the unit it is measured in (m, m2, m3, kg, t, No.), the content a description must carry, and the coverage rule that says what the resulting rate is deemed to include. It is organised around traditional building elements and is the default framework for state government building procurement and most large commercial work.
Queensland transport infrastructure is procured against the TMR Schedule of Rates, which is written to sit alongside the Main Roads Technical Specifications. The schedule is unusual in that it is both a measurement convention and a payment schedule at the same time, so the measurement basis and the basis of payment for an item are read together from the governing MRTS clause rather than from a separate rule book.
No. A method of measurement settles what an item is, not what it costs. It tells you that the tonne of reinforcement includes lapping and tie wire, which is precisely the information a first-principles build-up needs before it can price the item honestly, but it is silent on productivity, plant selection, crew composition and rates. Measurement defines the question; the build-up answers it.
Yes, provided the software treats classification as a set of parallel trees rather than a single code field on each item. In TX1:Trinity a priced item can be allocated across a delivery work breakdown structure, an AS 2124 schedule structure and a client chart of accounts simultaneously, using percentage splits where an item genuinely belongs to more than one branch. Nothing is measured twice and every tree sums to the same project total.
You get tender returns that are all technically priced and none of them comparable. Each tenderer applies its own coverage assumptions, so the differences between submissions reflect scope interpretation rather than efficiency or market position. The evaluation panel then normalises the returns by hand under time pressure, which is slow, undocumented and the usual root cause of a post-award variation argument.
Measure once, price once, classify as many ways as the job demands. Parallel code sets with percentage-split allocations, on a local-first Windows desktop built for Australian infrastructure.