If two bid documents give you two different quantities for the same work, do not pick one and move on, do not split the difference, and do not average them. Stop measuring that item, write down both quantities with the exact source of each one, check whether this project's own contract rules resolve the conflict, ask in writing if time allows, and if no answer arrives before bid day, bid on one clearly stated assumption with the difference priced as a visible alternate or qualification. A conflict handled this way stays visible and defensible. A conflict buried inside a lump sum becomes a change order argument later.
Who this is for: general contractors, subcontractors, and estimators who price work from issued bid documents and need a defensible number when those documents disagree with each other.
The Seven Conflicts an Estimator Actually Meets
1. Plan versus section or detail
A floor plan shows one wall length and a wall section shows another, or a detail calls out a different assembly thickness. Measure the item from both sources before you price it, and log the difference instead of choosing the first number you measured.
2. Schedule versus plan
A door, window, fixture, or equipment schedule counts a different number of items than a count taken from the plans. Schedules are often updated last after a design change, or not updated at all. Always compare a schedule count with a plan count, even when the difference is only one item.
3. Specification versus drawing
A specification section calls for one product, depth, thickness, or performance level, and a drawing note or schedule calls for another. This is also the classic product scope conflict: manufacturer, model, size, finish, or accessory differs between the two documents. A manufacturer cut sheet can prove whether a product can meet a requirement, but it does not change the requirement. The same applies to a subcontractor quote that prices a different product than the documents specify.
4. Figured dimension versus scaled dimension
A written figure on a drawing differs from a measurement scaled off the same drawing. Scale can drift with printing, scanning, and PDF handling, so a scaled measurement should never be presented as a figured dimension. Label it as scaled and check it against a figured or overall dimension.
5. Large scale versus small scale
A large scale detail and a small scale general plan show the same item differently. Details show how a junction works, and general plans show layout, so a detail can reveal a dimension the plan simplified away.
6. Old revision versus new revision
An addendum or revised sheet supersedes an earlier sheet, but an estimator working from a mixed set can easily price the superseded quantity. Revision date and addendum number matter as much as the number itself.
7. Architectural versus structural versus MEP
Each discipline measures the same space from its own drawings, and the three totals disagree. Ceiling heights, duct routes, slab openings, and wall types are the usual meeting points. Compare architectural, structural, and MEP quantities for the same space before pricing, not after the bid is submitted.
There Is No Universal Winner
The most common shortcut here is also the most dangerous: claiming that specifications always beat drawings, or that drawings always beat specifications. As a general rule, that claim is wrong.
Under the standard AIA A201 General Conditions, the contract documents are complementary. What is required by one is as binding as if required by all, and the form document itself creates no hierarchy between drawings and specifications. Some projects do have a hierarchy, but it comes from that project's own supplementary conditions or its own contract, not from a universal rule. One project's supplementary conditions may put specifications above drawings. Another project's model language, such as the CSI A503 model language, may order documents as modifications first, then the agreement, then addenda (with later addenda above earlier addenda), then supplementary conditions, then general conditions, then Division 1, then drawings and Divisions 2 through 49 together. A third project may use a municipal order that puts the agreement, bonds, proposal, special provisions, invitation, drawings, and standard specifications in yet another order.
The practical consequence is simple. Before resolving any conflict, read the precedence clause in this project's documents, if one exists. If no clause exists, do not invent one. Run this one line check first: find the project's General Conditions and Supplementary Conditions, search for the words precedence, priority, conflict, discrepancy, and inconsistency, and record what that project actually says.
Two within-drawing rules are much more stable across projects, stated here as usual practice with the same check-first warning. Figured dimensions govern over scaled dimensions, and large scale drawings govern over small scale drawings of the same date. Later dated documents govern over earlier documents of the same type. A revised A201 form makes the same points in its own priority list. Present that list as one form's approach, not as the rule for every project.
The Five Step Method, in Order
Step 1: Freeze the conflict
Stop measuring that item. Write down both quantities, both sources with sheet number, detail number, specification section, schedule name, revision date, and addendum number, and the unit for each one. A conflict without a source citation cannot be audited later.
Step 2: Check the set itself
Is one source superseded? Is one source a scaled measurement that a figured dimension contradicts? Is the schedule count taken from an older revision than the plan? Many conflicts dissolve once revision dates are compared.
Step 3: Check this project's precedence rule
If the rule answers the conflict, record the rule and the answer in the log, and bid that answer. If it does not, or no rule exists, move to step 4. Do not silently apply another project's rule to this project.
Step 4: Ask in writing before bid day, if time allows
A request for information (RFI) is the cleanest resolution. A good RFI contains the item, both quantities, both sources, the difference, the cost or schedule effect if known, and a clear question with a reply deadline tied to the bid date. An RFI that says only "please clarify" forces the design team to rediscover the conflict.
Step 5: Bid on a stated assumption, if no answer arrives
State the assumption in the bid, in plain words: which quantity was bid, which source it came from, and what the alternate quantity would add or deduct. Price the difference as a visible alternate or qualification where the bid form allows it.
Three Worked Examples (Clearly Labelled Hypotheticals)
Every number below is hypothetical. No unit prices are invented here: the price effect is the quantity difference times the rate in your own estimate.
Example A: A count conflict
A lighting fixture schedule lists 48 fixtures, and a plan count gives 44 fixtures. The difference is 48 minus 44, which equals 4 fixtures. As a percentage of the plan count, that is 4 divided by 44, which equals 9.1 percent. The bid assumption would read: bid on 44 fixtures per the plan count, with 4 additional fixtures priced as an alternate, pending the RFI answer.
| Item | Quantity A and source | Quantity B and source | Difference | Bid assumption |
|---|---|---|---|---|
| Lighting fixtures (hypothetical) | 48, fixture schedule | 44, plan count | 4 fixtures, 9.1 percent of plan count | Bid 44, alternate for 4, RFI pending |
Example B: Figured dimension versus scaled dimension
A hypothetical wall is 9 feet high. The figured dimension is 40 feet long, and a scaled measurement from the same drawing gives 38 feet. Figured area is 40 times 9, which equals 360 square feet. Scaled area is 38 times 9, which equals 342 square feet. The difference is 18 square feet, or 5.3 percent of the scaled area. In drywall sheets at 32 square feet per sheet (4 feet by 8 feet), the net counts are 11.25 sheets versus 10.69 sheets, before waste, joints, and openings. Under the usual within-drawing rule, the figured dimension governs.
| Measure (hypothetical wall) | Figured | Scaled | Difference |
|---|---|---|---|
| Length | 40 feet | 38 feet | 2 feet |
| Area at 9 feet high | 360 square feet | 342 square feet | 18 square feet, 5.3 percent |
| Net drywall sheets at 32 square feet each | 11.25 sheets | 10.69 sheets | 0.56 sheets, before waste |
Example C: Specification depth versus drawing note
A hypothetical slab area is 2,000 square feet. A specification calls for 18 inches of fill, and a drawing note calls for 36 inches. At 18 inches (1.5 feet), the volume is 2,000 times 1.5, which equals 3,000 cubic feet, and 3,000 divided by 27 equals 111.1 cubic yards. At 36 inches (3 feet), the volume is 6,000 cubic feet, and 6,000 divided by 27 equals 222.2 cubic yards. The difference is 111.1 cubic yards, exactly double. A factor of two on depth is a factor of two on volume, on trucking, and on compaction. This example is hypothetical, not the Hensel Phelps project.
| Fill depth (hypothetical, 2,000 square feet) | Volume |
|---|---|
| 18 inches per specification | 111.1 cubic yards |
| 36 inches per drawing note | 222.2 cubic yards |
| Difference | 111.1 cubic yards, double the smaller volume |
The Discrepancy Log: Your Original Artifact
Keep one log per bid, one row per conflict, and no row marked resolved by silence. A log with an empty answer column is still useful: it is the list of open items at bid review.
| Item | Quantity A and source | Quantity B and source | Difference | Precedence rule checked | RFI number and date | Answer received | Bid assumption | Alternate priced |
|---|---|---|---|---|---|---|---|---|
| Lighting fixtures (hypothetical) | 48, schedule | 44, plan count | 4, 9.1 percent | None found in this set | To be assigned | No | Bid 44 | Yes, 4 fixtures |
| Wall length (hypothetical) | 40 feet, figured | 38 feet, scaled | 2 feet, 5.3 percent of area | Figured over scaled | Not needed | Set rule applied | Bid figured 40 feet | No |
| Fill depth (hypothetical) | 18 inches, specification | 36 inches, drawing note | 111.1 cubic yards | Project clause to be checked | To be assigned | No | To be stated in bid | Yes, if form allows |
What Never to Do With a Conflict
- Do not average two quantities. An average is a third quantity that no document supports, and it cannot be defended in a review or a claim.
- Do not silently pick the larger quantity and call it conservative. It may be conservative for cost, but it can lose the bid, and it still hides the real question from the client.
- Do not silently pick the smaller quantity and hope the difference becomes a change order. Some contracts expressly require prompt notice of apparent errors and require the contractor not to take advantage of them. Even where that language is absent, it is a credibility problem when the conflict surfaces on site.
- Do not rely on a manufacturer cut sheet to override the contract documents. A cut sheet can prove whether a product can meet a requirement, but it does not change the requirement.
- Do not treat an unanswered RFI as an answer. If the design team did not reply, the conflict is still open, and the bid must say so.
- Do not bury the conflict in a lump sum. A lump sum with no quantity breakdown gives a reviewer no way to see which quantity was bid.
Patent Versus Latent: Why the Timing of Discovery Matters
This section is estimator practice guidance, not legal advice. A live dispute needs the project's own contract and professional advice.
A patent conflict is obvious on the face of the documents: a careful bidder reading the set would spot it. A latent conflict only appears after deeper measurement, coordination, or site work. On public work, courts have treated obvious conflicts differently from hidden ones. Where a conflict is obvious, a bidder may be expected to seek clarification before bidding, and a bidder who does not ask may lose the right to claim the extra cost later. Where a conflict is hidden, a bidder who reasonably relied on the documents may have a stronger position.
The Hensel Phelps line of cases is the instructive example. A specification calling for 18 inches of fill conflicted with a drawing note calling for 36 inches, the contract's own order of precedence clause said specifications govern, and the court treated that clause as resolving the conflict. Present that case as an example of a project's own clause doing the work, not as proof that specifications always win. The estimator's takeaway is practical: spot conflicts early, log them, and ask early. An addendum can fix a conflict for every bidder, an RFI answer can fix it before pricing, and a stated bid assumption can at least make it visible. A conflict found after bid day has only expensive options left.
Audit Before Pricing: The Five Checks
- Set check: every sheet and specification section carries a revision date and addendum number, and no superseded sheet is priced.
- Count check: every schedule count is compared with a plan count for the same item, and every difference is logged, even a difference of one item.
- Dimension check: every figured dimension is compared with an independent check, and any scaled measurement is labelled as scaled, never as figured.
- Cross discipline check: architectural, structural, and MEP quantities for the same space are compared before pricing, not after the bid is submitted.
- Bid review check: the bid review meeting opens the discrepancy log, not the price summary. Every open conflict has an answer, a stated assumption, or a priced alternate.
This method sits between two posts you may already use. Quantity Takeoff From PDF Drawings covers how to measure a set correctly, and Bid Day Checklist covers what to verify before you submit. This post covers the step in between: what to do when a correctly measured set still disagrees with itself. See also our construction estimating services, bid estimating services, and Quantity Takeoff Cost Per Trade in 2026.
Frequently Asked Questions
Should I always follow the specification when it conflicts with a drawing?
No. Under AIA A201 the documents are complementary and create no hierarchy. Check this project's General Conditions and Supplementary Conditions first.
What if the RFI is not answered before bid day?
Bid on a stated assumption: which quantity you bid, which source it came from, and what the alternate would add or deduct, priced as a visible alternate where the bid form allows it.
Is averaging two quantities ever acceptable?
No. An average is a third quantity that no document supports. Log both quantities and bid one stated assumption instead.
Send Your Plans for a Project-Specific Construction Estimate
If your bid set has a conflict you cannot resolve cleanly, do not guess your way past it. Send your plans for a project-specific construction estimate and tell us which quantities disagree. We will measure both sources, log the difference, and return a bid-ready takeoff with stated assumptions you can defend in review. Contact Estimate Services with your plans and bid date.
