The useful question after an AI takeoff is whether the quantities cover the scope you intend to price. A plausible total can hide omitted rooms, duplicate detections, or a wrong scale. Review against the drawing, not just the quantity list, and keep corrections traceable to their source.
1. Confirm the source before checking the result
Start with the drawing index, revisions, and bid instructions. Confirm that every required sheet has been processed and that superseded sheets have not been counted again. Then identify the boundaries: building, level, zone, trade, and alternate.
- Record sheet number and revision for each takeoff group.
- Separate new work, demolition, existing work, and owner-supplied items.
- Check for missing pages, rotated scans, cropped details, or unreadable tags.
- List anything requiring an RFI or a stated allowance.
An existing fixture may still require demolition or relocation labor even when it needs no new material purchase. Keep these conditions visible instead of deleting everything outside the new-work count.
2. Inspect counts by symbol type and zone
Review the overlay one group at a time. Start with groups that are ambiguous, expensive, or easy to confuse, then complete the remaining scope. A spot check can find an issue; it does not prove the rest of a bid is complete.
| What you see | What to check |
|---|---|
| A mark on the legend | A legend example is not installed equipment. Exclude it from the measured scope. |
| Two marks on one symbol | Inspect the source and remove only the confirmed duplicate. Nearby paired devices may be legitimate. |
| A missing mark under text | Zoom into the original PDF, identify the symbol and tag, then record a manual correction. |
| Several variants grouped together | Split by the schedule or specification, such as standard and emergency fixture types. |
| A room with no detected items | Check whether it truly has no scope or whether low contrast, cropping, or scale prevented detection. |
For example, the electrical showcase has 35 A2 fixtures and 21 B fixtures. If a result gives 56 fixtures in one undifferentiated group, the total alone cannot tell you which unit price or labor allowance belongs on each line. Review the types before accepting the total.
3. Check scale, routes, and boundaries
Verify the drawing scale using a known dimension, then test a second dimension. Repeat for details or sheets that use another scale. A length error also affects area: a 10% error in both dimensions turns a 100-square-foot rectangle into 121 square feet, a 21% difference.
Bluebeam’s page-scale documentation describes calibration and multiple scales within one PDF page. Those are useful checks regardless of whether the initial quantity pass was automated.
For linear measurements, inspect endpoints and route continuity. Check risers, drops, branches, and schematic sections separately. State whether the quantity represents route length, installed material, or a multi-conductor assembly.
For areas, inspect closed boundaries, openings, and exclusions. Keep plan area distinct from sloped surface area. Record the basis for deductions and allowances so another estimator can reproduce the result.
The count, linear, and area comparison gives a short checklist for selecting the right measurement method.
4. Reconcile plans, schedules, and estimate lines
Compare the reviewed counts with schedules and relevant details. Investigate differences by checking sheet coverage and scope. A schedule may cover the whole building while the plan shows one floor, so a mismatch is a question to resolve rather than a reason to overwrite one number.
Keep a small review log with the item, sheet/revision, original quantity, correction, reason, reviewer, and date. If a revision arrives, use those references to identify affected groups and related assemblies.
Separate measurement from waste and purchasing. For instance, the plumbing example measures 262 LF of vent pipe; a stated 10% allowance rounded up gives 289 LF. Retain both values. If a later review finds a missing 20-foot branch, correct the measured quantity before recalculating the allowance.
5. Release a documented quantity set for pricing
A reviewed takeoff should have a known drawing basis, consistent units, resolved quantity discrepancies, and a list of outstanding scope assumptions. Passing a quantity check does not settle material specifications, design compliance, supplier availability, or commercial terms.
- Confirm each priced line has a source or a clearly labeled allowance.
- Check that assemblies do not double-count items already priced separately.
- Separate base bid, alternates, and exclusions.
- Confirm the units expected by the price catalog.
- Record who reviewed the takeoff and which revision they reviewed.
Continue with the worked BOQ pricing guide, or see how the BuildVision construction agent fits into the takeoff-to-quote workflow.