Professional Practice: Conflicting Code Editions on a Permit
A plumber submits a permit application for a commercial building. The plans were prepared under the 2018 edition of the plumbing code, but the jurisdiction adopted the 2021 edition six months ago. The plumber argues that the design was completed before the adoption date and should be grandfathered. The plans show a grease interceptor sized under the older table, and the new edition requires a larger interceptor for the same fixture load. The plan reviewer must decide which edition governs and how to proceed.
1. Which code edition governs, and what factors should the reviewer weigh?
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The general rule is that the code edition in effect on the date the permit application is accepted governs the project, unless the jurisdiction has a specific grandfathering or vesting provision. The reviewer should check the local ordinance for the adoption date and for any provision that allows a project with prior design work to proceed under the earlier edition.
Factors to weigh: (1) the date the application was accepted, not the date the design began; (2) whether the jurisdiction has a vesting ordinance that fixes the code edition as of a prior date; (3) whether the change is a life-safety requirement that the jurisdiction applies retroactively; and (4) whether the project has already been permitted under the earlier edition.
The plumber's argument that the design predates the adoption is not, by itself, a legal basis for grandfathering. The reviewer should document the applicable edition in the permit file, cite the ordinance, and notify the plumber in writing. If the jurisdiction allows the earlier edition, the reviewer should record the basis. If not, the plans must be revised to the 2021 edition.
2. The grease interceptor sizing differs between editions. How should the reviewer handle the disagreement with the plumber?
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The reviewer should first confirm the fixture load and the sizing method required by the governing edition. The older table and the newer table may use different assumptions (for example, different gallons-per-fixture values or different retention times), so the reviewer should show the calculation, not just assert a number.
The reviewer should present the calculation in writing, identify the code section and table, and give the plumber a specific correction deadline. If the plumber believes the calculation is wrong, the reviewer should invite a written technical response with the plumber's own calculation and the basis for it. The reviewer should not negotiate the code requirement as a bargaining matter, but should correct genuine calculation errors.
If the disagreement persists, the reviewer should escalate through the supervisor or the board of appeals, as the local process provides. The reviewer should keep the tone professional, avoid personal criticism, and document every communication. The goal is a compliant installation, not a win over the plumber.