'Commercial Is Commercial': A Warehouse Becomes a Taproom
A 1962 two-story, 22,000-square-foot building (11,000 square feet per floor) of Type IIIB construction, unsprinklered, has been used as a warehouse (S-2) with a small office. A developer proposes the ground floor as a 1,500-square-foot taproom and restaurant (A-2, about 180 occupants) plus a 3,000-square-foot brewing area (F-1), with storage and mechanical space in the remainder; the second floor becomes 8,000 square feet of open office (B). The building has one enclosed interior stair, one exterior rear stair, and a freight elevator. The applicant submits the drawings as a 'Level 2 alteration' under the existing building code, with a note that 'no change of occupancy occurs because the building remains a commercial building,' and asks that the existing stairs and the absence of sprinklers be accepted as they are. The drawings show no shaft enclosure for the freight elevator and no accessible route to the second floor.
1. Is this a change of occupancy, and which provisions govern the review?
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Yes. Occupancy classification follows use, not the word 'commercial.' Converting S-2 to A-2, F-1, and B is a change of occupancy classification, and the existing building code's change-of-occupancy chapter governs in addition to its alteration provisions. The applicant's label as a Level 2 alteration does not control.
The review approach: classify each space by its proposed use; determine whether the building will be treated as a mixed occupancy or as separated occupancies, and check the required separations; then apply the change-of-occupancy requirements, which generally require the building to meet the requirements for the new occupancy, subject to the specific exceptions in that chapter. Verify that the new uses fit within the allowable height and area for Type IIIB construction, and check egress, fire protection, shaft enclosure, and accessibility.
Because the exceptions differ between editions, the first written comment should ask for a code analysis prepared by the design professional that cites the specific sections relied on for each existing condition the applicant wants to keep. A general note asserting 'commercial is commercial' is not a code analysis and should not be accepted.
2. What specific conditions should the reviewer evaluate before the plans can be approved?
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Work through the life-safety consequences of the new uses.
- Second-floor egress. 8,000 square feet of Business at 100 square feet per occupant is about 80 occupants. The single-exit allowance for Business occupancies is capped at 49 occupants, so two means of egress are required from the second floor. The exterior rear stair may count, but verify it is a compliant exit: enclosure, width, travel distance, and remoteness from the interior stair.
- A-2 egress and sprinklers. About 180 occupants in the taproom requires at least two exits and triggers the A-2 sprinkler threshold on occupant load. The brewing area introduces process hazards and needs its own review.
- Shaft enclosure. The freight elevator must be enclosed as required for the new arrangement, and the existing stair enclosure must be verified.
- Accessibility. The plans show no accessible route to the second floor; an accessible route is normally required where the new occupancy or alteration affects it, and this needs a documented determination rather than silence.
Each item should appear as a separate written comment with the code basis, so the applicant can respond item by item instead of re-submitting a narrative.
3. The applicant argues that the existing building code lets existing elements remain. How should the examiner respond?
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The existing building code does allow existing elements to remain in defined circumstances, but it is not a general grandfathering clause. The burden is on the applicant to identify the specific provision, show that its criteria are met, and show that the resulting level of safety for the new occupancy is acceptable. A change of occupancy moves the building into a different risk category, and the change-of-occupancy chapter generally requires compliance with the new-occupancy requirements unless a stated exception applies.
So the response is procedural and firm: ask for a section-by-section analysis of every existing element the applicant proposes to keep, the criteria met, and the supporting calculations. Identify which items the department will not accept without a formal modification request or appeal, such as the single stair serving 80 office occupants or the unenclosed elevator shaft. Confirm which edition of the existing building code is adopted locally, because the exceptions vary.
If compliance cannot be demonstrated, present the options: add sprinklers and a second compliant exit, enclose the shaft, or seek relief through the modification or appeals process. Approval should be issued only on the basis of the analysis, not on the applicant's assertion that the building has always been there.