How do you handle addenda and revisions in a steel bid?

A workflow that holds up

1. Log it on arrival. Record the date, the addendum number, the sheets affected and who sent it.
2. Get the whole sheet, not just the cloud. Revision clouds miss changes. Compare the new sheet against the old one.
3. Triage by impact. Structural sheets change your quantities. Architectural, mechanical and electrical changes can still move steel through stairs, openings, equipment loads and dunnage.
4. Re-take-off only what changed. Keep the original takeoff, mark what is superseded, and add the delta. Do not start again unless the change is large.
5. Re-price the delta. If quantities and prices were kept separate, this is fast.
6. Write down the basis. The bid should list the addenda acknowledged and the revision letter or date of each structural sheet priced.

What is the difference between an addendum, a bulletin and an ASI?

An addendum changes the bid documents during the bidding period and must be acknowledged on the bid form. A bulletin or ASI (architect's supplemental instruction) is more common after award and changes the drawings for construction. A revision is a new issue of a sheet, listed in the title block revision table. Different projects use these words loosely, so check the cover note rather than relying on the label.

During bidding, treat them all the same: read, log, compare, price.

Where do revisions hurt estimators?

Three recurring failures:

• Pricing Rev 2 while the GC awards on Rev 4.
• Catching the clouded change on one sheet and missing the unclouded consequence on another, such as a new opening on the plan and the beam it needs in a detail.
• Giving a last-minute addendum twenty minutes when the original set got two days.

Most bid busts come from revisions, not from the original count. A written revision log, with your price tied to named revisions, is the cheapest protection.

How do you reduce rework?

Keep your takeoff in a form you can update by sheet. With SteelFlo you can run the revised set as a new takeoff, and each box is tied to its sheet, so you can check the pages that changed against your earlier count. Start with the sheets the addendum lists, then check the sheets that reference them.

Also use RFIs. If a revision is unclear, ask in writing and state your assumption in the bid until you get an answer. See RFIs from your steel takeoff and our fuller guide to drawing revisions in steel estimating.

A simple revision log

Keep one table per bid. Update it the moment anything arrives:

The log serves three purposes. It tells you what is left to review, it tells your boss what changed the number, and it is evidence if there is a dispute about what you priced.

What should the bid say about revisions?

State the addenda acknowledged by number and date, the drawing issue each structural sheet was priced from, and any assumptions you made about unresolved items. Plain wording works: "Pricing is based on structural drawings S-001 through S-502 as revised through Addendum 3 dated the 14th. Items not shown or marked by others are excluded." Keep it short and specific. A vague qualification protects nothing, and a long one gets ignored.

Also set a validity period. Steel prices move, and a bid held for 90 days without escalation language can turn into a loss.

What if a revision arrives the day before bid?

Triage fast. Open the changed sheets, decide whether quantities move, and either price the delta or add an explicit allowance and say so. If you cannot review it properly, qualify the bid on the earlier revision and say that later revisions will be priced separately. That is better than guessing silently. Do not skip it, and do not claim to have priced something you did not read.