Handling addenda and revised sheets without redoing the takeoff

Addendum 3 arrives at 4pm the day before the bid with eleven revised sheets. The question is not whether you can re-measure everything — you cannot — but which conditions are actually affected and how quickly you can tell.

First pass: triage, do not measure

1. List the revised sheets from the addendum and match them to your sheet index.
2. For each revised sheet, note which scopes you measured on it.
3. Read the addendum narrative — it usually states what changed.
4. Compare revision clouds and delta triangles on the new sheets.
5. Produce a list of affected conditions before touching a measurement.

Many revisions do not change quantities at all — a note clarification, a detail reference, a spelling correction. Triage separates those from the grading revision that moves 3,000 CY.

Second pass: recalibrate, then re-measure

Revised sheets are re-plotted, and re-plotting occasionally changes the sheet size or the drawn scale. Treat every revised sheet as a new sheet for calibration purposes, even when the title block says the same scale as before.

Third pass: propagate

• Reissue a revised quantity sheet to any sub whose scope changed.
• Update derived quantities downstream — trench, base, restoration.
• Re-run coverage and ratio checks; addenda reopen omission risk.
• Acknowledge the addendum number on the bid form.

Keep the audit trail

Record which revision each quantity was measured from. When a bid is questioned, or when the awarded scope turns out to differ from what you priced, the record of "this quantity came from sheet C-4, Rev 2, dated 6/18" is the entire basis of the conversation. Without it, the discussion is about memory.

Contractors who handle addenda well are not faster measurers. They are better bookkeepers — they know within ten minutes what changed, and they spend the remaining time on the two conditions that actually moved.