Long-lead items do not fail on site. They fail three months earlier, on a Tuesday, when nobody placed the order because the required-on-site date still looked comfortable. This works backwards from the date you need it and tells you the last day you can order without hurting the programme.
Settings
Buffer to hold, in weeks
Contingency on top of the quoted lead time. Two weeks is a common minimum.
Amber warning at, in weeks of float
Below this the item is going amber and needs chasing
What you are waiting on
The lead time is the supplier’s, not ours. This tool does not know what anything takes to
arrive — you enter that, and it should come from a written quote, not a phone call.
Lead times move, and the quoted one rarely includes shop drawing approval, sample sign-off,
inspection, or the wait for a delivery slot on your own site.
Questions
Where do I get the lead time from?
From the supplier in writing, and ask what it excludes. The number people usually quote is manufacture only. Shop drawing preparation, your approval turnaround, sample sign-off, freight, and getting a delivery slot on a busy site all sit on top of it.
Why does it add a buffer?
Because the quoted lead time is a best case, and ordering with zero float means any slippage lands directly on your programme. The buffer is yours to set. Two weeks is a common minimum on imported or fabricated items.
What does red mean here?
That the latest sensible order date has already passed. It does not mean the item is impossible, it means the programme date is now at risk and somebody needs to know today rather than at the next site meeting.
Should I include shop drawing approval time?
Yes, and it is the most commonly forgotten one. On structural steel, facades, lifts and joinery the approval loop can be longer than the manufacture. Either add it to the lead time or hold a bigger buffer.
A spreadsheet of long-lead items works right up until nobody updates it. The paid system tracks the order against the work front it feeds, so a late item shows as a blocked work front instead of a line nobody has looked at since March.
This is a practical site-management tool. It is not legal, engineering or regulatory advice and does not guarantee compliance or a satisfactory inspection outcome. Requirements may vary by jurisdiction, project, contract and circumstances.
Want a person to look at it?
The tools above are free and yours to use. When you need the paperwork behind them reviewed by someone who has run sites, Obras HSE Services is a live consulting business in south-east Queensland.
SWMS review service — a marked-up review showing what is missing and why it matters.
