A tender programme can look convincing while depending on decisions nobody has agreed to make. A transformer is assumed to arrive on a particular date. A room is assumed to be available. A design package is assumed to be complete enough for procurement. The bars line up; the conditions behind them remain invisible.
For a contractor or client reviewing a data centre bid, the useful question is: what has to be true for this completion date to remain credible? A short, structured assumptions register makes that question answerable. It also helps distinguish a competitive delivery strategy from a date achieved by hiding unresolved work.
Start with the boundaries of the tender
Identify what the programme includes, who supplies each major package and where responsibility changes hands. Owner-procured equipment still needs a place in the construction logic. A utility connection outside the contractor’s scope can still govern energisation. “By others” is a responsibility description, not a reason to omit a dependency.
Use separate milestones for the information, access or equipment that another party must provide. Link each milestone to the work it enables. Record the source of its date: a confirmed commitment, a supplier quotation, a client requirement or a planning assumption. These are different levels of confidence and should be reviewed differently.
Use an assumptions register that can change a decision
| Field | What to record |
|---|---|
| Assumption | The specific condition being relied upon, not “design on time”. |
| Affected work | Programme activity IDs and the delivery milestone they support. |
| Evidence | Document revision, quotation or correspondence supporting the date. |
| Owner and deadline | Who can confirm it, and when confirmation is needed. |
| Alternative | What changes if the condition is not met. |
For example, an assumed switchroom release date should identify what “release” means. Is the room weather-tight, structurally complete, accessible for delivery and ready for the particular installation? Agree the relevant requirements with the responsible disciplines. Do not let one milestone silently mean four different things.
Test the assumptions that could move completion
Prioritise assumptions connected to critical and near-critical work, scarce resources or irreversible procurement decisions. Prepare a small number of alternative programmes using the same scope, calendars and calculation settings. Change the assumption being tested, then examine the resulting paths to the required milestones.
Illustrative example: a bid assumes an equipment release on 1 March. The supplier can only confirm a slot after technical approval. Model a later approval and the resulting release; do not simply add a matching delay to project completion. Other available float, installation readiness and commissioning dependencies determine the actual effect.
Show the decision that keeps the preferred scenario available. This might be an earlier design review, agreement on an equipment specification or confirmation of a delivery route. An assumption without an owner and a decision date is difficult to manage after award.
What should accompany the tender programme?
- A scope and interface statement aligned with the tender documents.
- A clear account of working calendars, access restrictions and major resource assumptions.
- A list of unresolved approvals and externally controlled milestones.
- A narrative explaining the driving sequence and the most sensitive assumptions.
- A record of the alternatives considered and the decisions needed to support the offered dates.
The programme narrative should help a reviewer challenge the logic without reconstructing the entire schedule. Keep it specific to this project; a standard disclaimer page does little to explain how a campus, its utility infrastructure and its buildings will be delivered together.
Carry the reasoning into delivery
At award, reconcile the assumptions against the agreed scope and current evidence. Preserve the tender record, identify what has changed and develop the delivery programme through the applicable review process. Do not present tender assumptions as confirmed commitments merely because the contract has started.
A useful tender programme leaves the delivery team with a reasoned starting point: dates, dependencies, unresolved conditions and the decisions that will resolve them.
Further reading: the GAO Schedule Assessment Guide provides a broader framework for assessing reliable schedules.
Put the next decision on a sound footing.
Our programme consultancy supports tender, construction and commissioning planning. For an existing programme, explore a schedule health check.