Every tender set of reasonable size contains contradictions. The drawings show one thing, the specification requires another, and the schedule on sheet three lists a third. This is not negligence on the designer's part. It is what happens when a document set is assembled by several disciplines under a deadline.
The question is never whether the set contradicts itself. It is who absorbs the contradiction, and that is decided by a clause most estimators have never read.
The order of precedence is written down
Somewhere in the general or supplementary conditions there is a precedence clause. It ranks the documents so that a conflict between any two has a defined winner.
The rankings vary more than people assume. Some sets put the specification above the drawings. Some put figured dimensions above scaled ones but leave drawing-versus-specification unaddressed. Some rank addenda above everything, which means the fourth addendum silently outranks the document it appears to be amending.
Find that clause on day one and read it as a pricing instruction, because that is what it is. It tells you which of two conflicting requirements you are obliged to price.
1. Where the conflicts usually are
The recurring ones are predictable enough to look for deliberately.
Schedules on drawings against the corresponding specification section — door, window, finish and equipment schedules are the classic offenders, and the drawing schedule is usually the one that was updated last. Details showing an assembly that the specification does not list as acceptable. Quantities implied by a plan that the bid form contradicts. And general notes on the cover sheet that quietly override the discipline sheets behind them.
2. Precedence does not always resolve it
A precedence clause resolves conflicts between document types. It does not resolve a conflict inside one document, and those are common: two details on the same sheet showing incompatible assemblies, or a specification section that references a standard the same section elsewhere excludes.
It also does not resolve a conflict that is a gap rather than a contradiction. Where neither document addresses something, precedence has nothing to rank, and the default under a lump sum is that the work is inferred from the intent of the documents — which in practice means it is yours.
3. The question period is the only cheap fix
An ambiguity resolved by a written answer during the question period costs one email. The same ambiguity resolved after award costs a change order negotiation you may lose.
This is the single highest-return activity in the pre-bid period, and it is systematically underused because it feels like admitting you do not understand the documents. It is the opposite. A well-framed question demonstrates that someone has read the set closely enough to find a genuine conflict.
Ask precisely. Cite the sheet and the specification section, state the two requirements, and ask which governs. A vague question produces a vague answer that resolves nothing and is now on the record.
4. When the window has already closed
Sometimes the conflict is found after the question period, which happens routinely because the conflicts surface during detailed takeoff and takeoff finishes late.
At that point there are three honest options: price the more expensive interpretation and stay compliant, price the cheaper one and state the assumption explicitly in your clarifications, or price the cheaper one and say nothing.
The third is the common choice and it is the one that produces disputes. The second is defensible if the clarification is permitted by the instructions to bidders — and worth checking, because some tenders treat any qualification as grounds for rejection.
Pricing the ambiguity
An unresolved conflict is a priced risk, not a rounding error, and it should be visible in the estimate rather than buried in a rate.
Carry it as a named allowance with the two interpretations and their delta recorded. If the job is won, that record is the opening position in the first change-order conversation, and it was written while the reasoning was fresh rather than reconstructed a year later from memory.
The firms that handle this well are not the ones that find every contradiction. They are the ones that write down the contradictions they found, what they assumed, and why — so that the assumption is a decision the firm made rather than one an estimator made silently on a Tuesday.
