Reference lead times by stage and project size
The table gives indicative production times for the economist's principal assignments, in working days from receipt of a complete file. They assume a clear brief, complete drawings and assumptions agreed at the outset.
| Assignment | Small project, under 5 packages | Medium, 5–12 packages | Large, over 12 packages |
|---|---|---|---|
| Outline estimate | 1 – 2 working days | 2 – 3 working days | 3 – 5 working days |
| Developed-design measure | 2 – 3 working days | 4 – 6 working days | 7 – 10 working days |
| Complete tender package | 5 – 7 working days | 8 – 12 working days | 15 – 25 working days |
| Tender analysis | 2 – 3 working days | 3 – 5 working days | 5 – 8 working days |
| Analysis report | 2 – 3 working days | 3 – 5 working days | 5 – 8 working days |
| Final account, per package | 2 – 3 working days | 3 – 5 working days | 5 – 7 working days |
Note: these run from receipt of a complete file — dimensioned drawings, agreed assumptions, engineering layouts available for the tender package. Any wait for missing documents is added.
ℹ Why does the tender package take so long? A complete package on a medium-sized project typically means 8 to 12 specifications of 15 to 30 pages each, as many structured pricing schedules, plus the administrative conditions and the tender rules. The volume produced is of the order of 150 to 300 pages of written and technical documents. It is the bulkiest deliverable of all the cost stages, and the one whose quality bears most directly on the quality of the offers received.
What makes lead times slip
In practice the real durations often exceed the reference figures — not because the economist is slow, but because the conditions for starting were not met. The table identifies the most frequent causes and how to prevent them.
| Factor | Effect on the lead time | How to avoid it |
|---|---|---|
| Incomplete or undimensioned drawings supplied | + 30 to 100 % | Check the drawings are complete before commissioning |
| Changes of brief mid-assignment | + 20 to 80 % according to scale | Freeze the brief before commissioning the studies |
| Back-and-forth on assumptions not settled at the outset | + 1 to 3 days per cycle | A complete brief with assumptions agreed at commission |
| Waiting for the engineering layouts | Blocking on the technical packages | Coordinate their issue before commissioning the package |
| Coordination with several engineers on the technical specifications | + 3 to 7 days | Plan the exchanges from the start of detailed design |
| Long internal approval on the client's side: committees, lawyers | Variable, outside the economist's control | Anticipate the client's internal approval circuits |
The factor most frequently under-estimated is waiting for the engineering layouts. On a project with substantial services packages, the economist cannot write the corresponding specification without the engineer's layouts and calculations. If those arrive two weeks after the assignment starts, the package will be delivered two weeks later, whatever the economist's productivity.
The typical tender-package programme
Week 1: start-up and framing
The economist takes in the file, identifies the packages to be tendered, structures the plan of the documents — the list of specifications, the organisation of the schedules — and asks for what is missing. This is the point at which it matters most to clarify assumptions and undefined points: every question left unresolved in week 1 becomes a round trip in week 2 or 3.
Weeks 2 and 3: drafting
The heart of the assignment. The economist writes the specifications package by package, starting with the ordinary ones they command — structure, finishing trades, finishes — then the technical ones while waiting for or coordinating with the engineers. The pricing schedules are produced in parallel, consistent with each package's specification. Interfaces between packages are defined and documented in each.
Week 3 or 4: review and coherence
Before delivery the economist cross-reads specification against schedule: every item described in one is present in the other, and vice versa. Interfaces are checked both ways. The administrative conditions are reread for consistency with the programme, damages and conditions announced in the tender rules.
Delivery and review
The package is delivered in editable format, Word and Excel, with a covering note summarising the structuring choices: number of packages, lump-sum schedule or priced bill, principal specification assumptions. A presentation meeting is held with architect and client for approval before issue to contractors.
What a "complete file" means
For an outline estimate
- Sketch or site plans with approximate areas
- Location and project type: housing, offices, public building, refurbishment
- Level of specification sought: standard, intermediate, high-end
- Known constraints: occupied premises, special foundations, asbestos
For a developed-design measure
- Dimensioned floor plans, all levels
- Elevations and sections
- A detailed brief with habitable or floor areas
- Technical choices settled: structural type, insulation, mechanical systems where defined
For a complete tender package
- Floor plans, elevations, sections and details at developed or detailed design
- Structural drawings from the structural engineer
- Outline mechanical and electrical layouts from the services engineers
- A technical brief
- An agreed list of the packages to be tendered
Lead times at Quostra
Quostra commits to firm lead times at commission, conditional on receipt of a complete file. The delivery window is calculated automatically from the date the file arrives and communicated to the commissioner as soon as the assignment is confirmed.
For routine assignments — outline estimate, developed-design measure — Quostra commits to 72 working hours from receipt of a complete file. For tender package and award assignments the lead time is stated package by package according to the complexity of the project.
You have better things to do. Submit your project on quostra.com; the delivery time is calculated automatically when your file arrives.
In summary
Production times for a cost study run from one or two days for an outline estimate on a small project to 15 to 25 days for a complete tender package on a large one. They are conditional on the quality of the file supplied: complete drawings, agreed assumptions, engineering layouts available. The principal causes of slippage sit upstream of the economist — incomplete drawings, changes mid-assignment, waiting on the engineers. Preventing them through a rigorous brief at the outset is the best way to hold the tender programme.