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Cost deliverables by design stage: a complete guide for architects and economists

📐 Article7 min read

Every design stage carries its own set of cost deliverables. Together they are the financial spine of the project: they let the client decide on an informed basis at each step, and they progressively engage the design team's liability.

The deliverables at a glance

Stage Cost deliverable Method Accuracy Contractual role
ESQ Order of magnitude Ratios per m² ±25–30 % Informative, no commitment
APS Estimate by trade Refined ratios and breakdown by trade ±15–20 % Provisional commitment on forecast cost
APD Quantities by individual element Measured off the drawings ±10 % Definitive commitment, basis for any penalty
PRO Specifications, quantities, priced bill Precise measurement and specification Contractual The documents of the future contract
DCE Priceable schedule, list of documents n/a Contractual The basis on which bids are compared
ACT Comparative table and analysis report Analysis of the bids n/a Support for the client's decision
DET Validated applications, contract tracking sheet Actual progress Monthly Financial control of the site
AOR Final account Settlement of every contract Definitive Financial closure of the operation

The deliverables in detail

ESQ, the order of magnitude: what it is and what it is not

The ESQ order of magnitude is the first figure the project produces. It is built by applying cost ratios per square metre of floor area, which vary with building type, specification level and geography.

Its purpose is not to fix the final budget but to confirm that the brief and the money broadly agree. A 500 m² office project in Paris estimated at 600,000 € excluding VAT, or 1,220 €/m², reveals the gap against market ratios immediately, those running from 1,840 to 2,550 €/m² depending on specification.

Accuracy: ±25 to 30 %. To be communicated only as a band, never as a single figure.

APS, the estimate by trade

The APS estimate structures the cost by broad families of work: structure, façades, external joinery, finishing trades, technical packages. That breakdown exposes the dominant items and prepares the trade-offs should the envelope be exceeded.

It is also the first document to show the peripheral items so often forgotten at ESQ: external works, landscaping, design and consultants' fees, insurance, finance costs. That is the difference between the works cost and the total development cost of the construction.

Works cost excluding VAT The sum of the trade contracts. It is the basis on which design fees are calculated.
Plus design and consultants' fees 7 to 14 % of the works cost according to appointment and complexity.
Plus specialist studies Ground investigation, asbestos survey, site coordination, health and safety coordination, technical control. 1 to 3 % of the works cost.
Plus damage insurance 0.5 to 1.5 % of the works cost. Mandatory before the site opens.
Plus finance costs Variable with the funding arrangement. To be included for a developer.
Equals the total development cost of the construction The complete envelope, excluding land and excluding VAT.

APD, the quantities: the key to the commitment

The APD quantities are the financial pivot of the appointment. They list the individual elements with their units, square metres, linear metres, cubic metres, number or lump sum, and the quantities measured off the drawings, to which reference unit rates from the economist's database are applied.

Their quality rests on two things: completeness, with no element forgotten, and the reliability of the rates, current with the market and adjusted for location. Quantities built on old rates or on uncorrected national data under-estimate the real cost systematically, and never more so than in a period of material inflation.

PRO and DCE: specification, pricing schedule and priced bill

The pricing schedule is the contractual form of the APD quantities, laid out so contractors can price it. Each element is presented with its description, unit and quantity, and two blank columns for the unit rate and the total the contractor will enter.

The priced bill completes the schedule on remeasurement contracts, and wherever quantities are hard to determine in advance. It then becomes the reference for valuing additional works, or omissions, during construction.

ACT, the comparative table: from bid to decision

The comparative table is the summary deliverable of the tender analysis stage. Package by package and sub-package by sub-package, it sets the bids received against the economist's PRO estimate. It comes with an analysis report documenting the technical observations and giving a reasoned award recommendation.

That document is what lets the client take an informed award decision, and defend it if the award is later contested.

DET, the contract tracking sheet

The contract tracking sheet is the instrument of financial control during construction. Kept by the economist or the design team, it records for each contract the original amount, the instructions being valued, the variations signed, the provisions for identified risks, and the updated forecast final cost.

A tracking sheet kept properly reveals budget drift early, while there is still time to act, rather than at handover when there is not.

AOR, the final account: financial closure

The final account is settled package by package. It carries the original contract amount, the signed variations, the instructions valued definitively and any liquidated damages. The contractor's signature is irrevocable: it is a waiver of any later recourse over the sums paid.

What Quostra takes on

From the ESQ order of magnitude to the final account at handover, the construction economist produces all of these. Each document is several days of technical work, and each engages the design team's liability towards the client.

Quostra, the construction economist on demand Cost estimates, pricing schedules, developer appraisals, summary notes. The deliverables that take you days today, taken on by a dedicated economist. You have better things to do. Submit your project and an economist takes over. → quostra.com

Sources: Léonard Hamburger, Maître d'œuvre Bâtiment, 3rd ed., Eyrolles, 2016 · Yves Widloecher and David Cusant, Manuel de l'étude de prix, 4th ed., Eyrolles, 2018.

Reference basis of the figures

The ratios per square metre and per unit on this page are stated in January 2026 values. They were updated from January 2025 values, the basis retained for this whole group of articles, using the BT01 all-trades index published monthly by INSEE on its 2010 base: 132.0 in January 2025, 134.7 in January 2026, a coefficient of 1.0205.

Global amounts quoted in worked examples, along with rents, running costs and revenues expressed per year or per night, stay at their original basis: a building cost index does not apply to them.

To bring the ratios forward, apply the usual revision formula: updated value = page value × (BT01 for the month in question / 134.7). The BT01 measures contractors' input costs, labour at 44.9 % and materials at 36.5 %, not the prices actually tendered.

Frequently asked questions

From the ESQ order of magnitude built on ratios to the final account at handover, the economist produces estimates, measured quantities, specifications, pricing schedules, comparative tables and tracking sheets.

The pricing schedule is the lump sum document the contractor completes with its rates. The priced bill is a schedule of unit rates used for additional works.

It records the original amount, the instructions, the variations and the provisions. It reveals budget drift while there is still time to act.

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