Switchgear, Zero Float, and a Fixed Opening Day
You are the design-build project manager for a $60M school with a 52-week electrical switchgear lead time. The electrical subcontractor cannot release the purchase order until the owner approves the 90% design of the main electrical room, and that review has been sitting for three weeks. Energization must precede roughly six weeks of testing and commissioning before occupancy. The contract completion date is the first day of school, which the board has declared immovable. Your Monte Carlo model with current logic gives P50 at the contract date and P80 fourteen days later. Someone on the team proposes putting the switchgear into a separate early-release package.
1. Work the arithmetic before discussing mitigation. Is the current plan even feasible?
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Back-plan from the fixed date rather than forward from today.
- Occupancy at month 12.
- Energization at month 10.5, allowing the six weeks of testing and commissioning.
- Switchgear on site around month 10, allowing installation, terminations, and inspection.
- Purchase order released 52 weeks earlier: approximately month -2.
The conclusion is uncomfortable and important: the PO is already overdue. Every further week of approval delay is pure project delay, not float consumption. The approval activity has zero - in fact negative - float, and the Monte Carlo distribution is describing a schedule that cannot meet the board's date regardless of which percentile you read.
Before you take that to the board, interrogate the lead time. Fifty-two weeks is a quotation that assumes a release date; ask the fabricator what the lead time is from a release next month. Then re-derive the true latest PO date and the real approval window. Lead with arithmetic, not with risk language - numbers survive a boardroom.
2. How do you present P50/P80 to a board that has fixed the date?
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Never present P50 as a commitment; it is by definition a coin flip, and presenting it as a plan guarantees that half the time you will be explaining a failure you predicted.
Frame it in one sentence: "The current plan has a 50% chance of meeting the date; reaching 80% requires 14 days of mitigation or a compressed commissioning sequence." A fixed date is a constraint to be bought down, not a schedule outcome.
Then put real options on the table with cost and residual risk attached:
- early-release package for the switchgear, decoupling procurement from design approval (owner-held contract or assigned PO);
- temporary generator power to begin commissioning before permanent energization;
- resequencing dry-in and interior finishes ahead of energization to protect downstream work;
- phased occupancy with a temporary certificate of occupancy.
Ask the board to select, in writing, and record the residual risk they are accepting. A constraint accepted silently becomes a claim later; a constraint accepted on the record becomes a shared decision.
3. The subcontractor offers a 40-week lead time at a 12% premium. Do you buy it?
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Verify the offer before you value it. Call the fabricator directly, obtain the 40-week commitment in writing tied to a specific release date, and confirm what changed - a re-quote with different testing or a genuine slot. A premium paid for a lead time that evaporates at the next schedule update is money spent for nothing.
Then value the time. Twelve weeks recovered against the cost of delay: extended general conditions, temporary power, lost use of the building, and any liquidated damages. Compare with 12% of the equipment value. The comparison only works if the twelve weeks actually land on the controlling path - a gain on a non-critical activity buys nothing.
Guard the commitment: not-to-exceed amount, milestone payments tied to documented fabrication progress, and a delivery guarantee with a remedy for late shipment.
Finally, update the risk register and the contingency draw in the same meeting. An approved mitigation without a contingency adjustment is how projects quietly lose their reserve.