Evaluation Report Offered for a Rated Garage Separation Wall
A contractor proposes an alternative for the 1-hour fire-resistance-rated wall separating dwelling units from an enclosed parking garage in a four-story, Type III-A, nonsprinklered R-2 building. Instead of a prescriptive assembly, the contractor submits a manufacturer's ICC-ES evaluation report recognizing a proprietary steel-stud and gypsum assembly as a 1-hour rated wall.
Two conditions of use in the report stand out: the assembly is recognized only in buildings of Type V construction protected throughout by an automatic sprinkler system, and stud spacing is limited to 24 inches on center. The submittal drawings show 24-inch spacing, no sprinkler protection, and no other changes to the building.
1. Can you approve the wall on the strength of the evaluation report? Walk through exactly what you check.
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No - not on this submittal. An evaluation report is evidence the building official may rely on, not an automatic entitlement to approval. The conditions of use printed in the report are part of what was evaluated and are binding.
The review sequence:
- Is the report current and applicable? Verify the edition, that it has not been superseded, and that the issuing body is recognized by the jurisdiction.
- Does the product match? Model numbers, stud sizes and gauges, board type and thickness, fastener type and spacing, insulation. A generic "equivalent" product is not what was evaluated.
- Do the conditions of use match this building? Here they do not. The report is limited to Type V, sprinklered construction; the building is Type III-A and nonsprinklered. Two assumptions behind the rating are false.
- Is the required rating correct? Confirm the separation required between the R-2 units and the S-2 parking occupancy, and confirm that rating plus any opening protection is what is being provided.
Because the conditions of use cannot be met, the report does not support approval. Issue a written comment stating that reason specifically, and give the applicant the compliant paths forward.
2. The applicant asks what it can do instead. Identify the compliant paths and what you require for each.
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Three routes, each with its own documentation:
1. Prescriptive assembly. Use a rated assembly from the code's own recognized assemblies or from a recognized listing, configured exactly as published. The burden is on the applicant to show the assembly matches the publication (stud size, layers, fasteners, insulation). This is usually the fastest path and requires no alternative approval.
2. A tested assembly qualified for these conditions. Submit an ASTM E119 test report or listing for the assembly as built, including the specific stud and board configuration, with a clear statement that the tested assembly was not conditioned on sprinkler protection or Type V construction.
3. Alternative materials and methods. Submit a formal request under the code's alternative materials provision, with test data, engineering analysis, or a new product evaluation that addresses the actual conditions. The official must then make and document an independent finding of equivalency. The official may require tests at the applicant's expense.
In all three, the approval must be recorded in the permit file and reflected in the approved plans, because the field inspector will be verifying against those documents.
3. The contractor offers a sealed letter from a registered design professional stating that, in the engineer's opinion, the assembly "provides equivalent fire protection." What weight do you give it, and how do you respond?
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Treat the letter as an assertion, not a basis for approval. The alternative-methods provision asks the building official to find equivalence based on accepted data; a professional opinion that does not identify the test standard, the analyzed configuration, or the engineering basis is not data. A seal certifies who prepared the work - it does not transfer the code decision to the designer.
A design professional's analysis can carry weight when it is substantive: reference to E119 test results for a closely comparable assembly, heat-transmission or structural calculations addressing the difference from the tested condition, and a stated conclusion tied to the required rating. Even then, the official must make the finding.
Respond in writing, not verbally:
- State that the letter alone does not establish equivalence and identify what is missing.
- Invite the three compliant paths with specific documentation requirements.
- Record the decision, the date, and the reasoning in the permit file, because this is the kind of decision that gets appealed.
- Note the appeal deadline and route in the response so the applicant's options are clear.
Keep the tone factual. The applicant is entitled to a written basis for a denial, and a well-written file note is what protects the jurisdiction if the matter goes to the board.