Determining the drawing basis for completion settlement: as-built drawings govern (as-built drawings + change/visa documents jointly verify the work actually completed), with construction drawings serving as the benchmark for contract-scope definition and change-difference comparison

Topic Positioning

This card answers the drawing-basis question in completion settlement: whether settlement follows the as-built or the construction drawings, and what role each plays in settlement measurement. For employer and contractor in handling completion settlement and compiling/reviewing settlement documents to fix the graphical basis of measurement and verification.

Core Conclusions

Conclusion: completion settlement is based on the as-built drawings — more fully: the qualified work actually completed is jointly verified by "as-built drawings + design changes, engineering changes, visas and other change documents"; the original construction drawings do not serve alone as the settlement measurement basis.

1. In the settlement-basis list, the graphical entry is "as-built drawings". GB/T 50326-2017 Code for Construction Project Management, Clause 18.3.3: completion settlement shall be based on: (1) contract documents; (2) as-built drawings and engineering change documents; (3) relevant technical data and material-substitution approvals; (4) pricing documents and BOQs; (5) visas and claim materials confirmed by both parties. — The list names only "as-built drawings", not construction drawings separately.

2. What settlement measures is "qualified work completed and due for measurement". GB/T 50500-2024 Clause 7.1.1: the contract works are measured per the work the contractor has completed per the contract and that is due for measurement, quantities computed per the calculation standards and supplementary rules agreed by the parties; re-measurement, change measurement, and new-work measurement proceed from the qualified work completed and due for measurement and from the construction drawings and change instructions issued by the employer. Clause 7.4.1: whether the works use a unit-rate or lump-sum contract, comparison of the change instructions issued or confirmed by the employer and the actual construction drawings against the contract drawings identifies the difference BOQ items as engineering-change items; differences between the contract drawings and the contract BOQ are BOQ defects — corrected per the rules for unit-rate contracts, not adjusted for lump-sum contracts. — The construction (contract) drawings are the "comparison benchmark"; the as-built state (recorded by the as-built drawings) determines the settled quantities.

3. Relation between as-built and construction drawings (JGJ/T 185-2009 Specification for Management of Construction Documentation, Clause 4.2.4). As-built drawings shall truthfully reflect the actual state of the completed works and shall be drawn from the construction drawings, drawing-review records, design change notices, and negotiation records (including technical verifications); where the construction drawings are unchanged, they may be stamped with the as-built seal to become the as-built drawings; as-built drawings shall carry the as-built seal and responsible persons' signatures. The clause commentary: negotiation content that changes drawing content must be redrawn onto the drawings; commercial negotiations unrelated to drawing content need not be reflected. — No changes: the stamped construction drawings are the as-built drawings, equivalent; with changes: the changed content is redrawn into the as-built drawings, and settlement follows the as-built drawings.

4. Measurement results signed by both parties are the settlement basis. GB/T 50500-2024 Clause 7.1.8: measurement results signed and confirmed by the parties serve as the basis for price adjustment and settlement, except where the contract provides otherwise, the parties expressly limit them to progress-payment purposes, or the results are rough estimates.

5. Settlement compilation/review bases must come as "drawings + change formalities". GB/T 51095-2015 Clause 8.2.4 (compilation basis) includes: laws/regulations affecting the contract price; site survey and re-inspection records; construction contracts, specialty subcontracts and supplements, material/equipment purchase contracts; pricing bases issued by cost authorities; tendering and bid documents; construction drawings, approved construction organization designs, design changes, negotiations, claims and visas, meeting minutes; material/equipment price confirmations; price additions or reductions confirmed by both parties; approved commencement/completion or stoppage/resumption reports; other relevant materials. Clause 8.3.4 (review basis) adds the review-consultancy contract and submitted settlement documents. — Construction drawings alone cannot verify the work actually completed.

6. Match by scenario:

• No changes at all: the stamped construction drawings are the as-built drawings — equivalent;
• With design changes/negotiations: verify by as-built drawings (changes redrawn in) + change formalities;
• Changes not redrawn/confirmed: verify by confirmed change documents and visas; parts not reflected in the as-built drawings (especially concealed works) lack support and are easily reduced at settlement;
• Fixed lump-sum contracts: adjust only the agreed adjustable contents per the contract; the tender construction drawings define the lump-sum scope.

Applicable Boundaries

• Applies to determining the drawing basis at the domestic employer-contractor completion-settlement stage; both unit-rate and lump-sum contracts (measurement differences per GB/T 50500-2024 Clause 7.4.1).
• Contract prevails: express contractual provisions on settlement bases and measurement rules govern (Clause 7.1.8's "unless otherwise agreed by the contract").
• Settlement drawings shall be jointly confirmed per the contract by the employer, contractor, designer, and supervisor, forming complete settlement drawings with schedules of each discipline (paper and electronic); fixed lump-sum contracts shall also provide the tender construction drawings and electronic versions (T/ZBD 100.5-2023 Clause 2.2.4).
• As-built drawings must be truthful: if as-built drawings of concealed foundations, structures, underground pipelines, etc., disagree with the physical works, great difficulty and loss will be caused to the user (JGJ/T 185-2009 Clause 4.2.4 commentary).
• This card does not replace review of specific contract clauses; settlement risks where changes were not carried into the drawings should be judged against the contract's change procedures and evidence requirements.

Further Reading

• GB/T 50326-2017 Code for Construction Project Management, Clause 18.3.3: settlement-basis list (graphical entry "as-built drawings and engineering change documents").
• GB/T 50500-2024 Standard for BOQ Valuation of Construction Works, Chapter 7 "Measurement of contract works": Clause 7.1.1 (principle), 7.1.8 (use of measurement results), 7.4.1 (change measurement and BOQ defects).
• GB/T 51095-2015 Code for Construction Cost Consultancy, Clauses 8.2.4 and 8.3.4: compilation and review basis lists.
• JGJ/T 185-2009 Specification for Management of Construction Documentation, Clause 4.2.4 with commentary, Appendix D (as-built drawing methods), Appendix E (folding methods).
• T/ZBD 100.5-2023 Work Guideline for Settlement Review of Construction Works, Clause 2.2.4: four-party confirmation of settlement drawings and as-built documentation requirements.
• Local reference: DB37/T 5130-2018 Specification for Construction Cost Consulting Services, Clause 8.2.4 (compilation basis list, consistent with the national caliber).