Drawing sets, overlays, and patches: the workflow addenda were made for

Addenda used to mean re-doing takeoff. With drawing sets and patch overlays, you slip a revised detail on top of the original and keep your measurements intact.

You're two days into a bid. Piers are counted, footings are traced, slabs are calibrated. Addendum 2 drops. Fourteen sheets are revised, most of them minor detail changes. Historically, you have two bad options: redo the takeoff on the affected sheets (hours), or hope the changes don't affect your quantities (dangerous).

A drawing set is a named bundle of sheets — "Bid Set," "Addendum 1," "Addendum 2," "For Construction." You assign each uploaded sheet to a set. When you're taking off, you pick which set is active. The measurements are shared across sets on the same base sheet, so switching sets doesn't lose your work.

Overlay. A whole revised sheet floated on top of the original at reduced opacity. You compare old vs. new visually, catch what changed, and update targeted measurements.

Patch. A cropped region of a revised sheet slipped over the same region of the original. Same visual comparison, but only the piece that changed. You keep the rest of the original visible and undisturbed.

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