Appeal 33595

2022 OSSC 404.5

A smoke control system shall be installed in accordance with Section 909.

Appeal to maintain existing condition as permitted and built under permit number 20-227703-CO without smoke control system in the existing atrium by Appeal ID #24044 dated 9/30/20.

The Health Technology (HT) Building is an existing Type II-A Building located at the PCC Sylvania Campus in SW Portland. Built in 1964, it is a fully sprinklered four-story building, including the basement, and contains partially separated Group A-3, B, and S-1 mixed occupancies. The building is located on a sloped site with exits directly to the exterior on all floors of the building.

The proposed scope of work includes renovation of the West portion of the building, including reconfiguring interior spaces, converting the former natatorium (A-4 Occupancy) to classrooms (B Occupancy), and adding 9,087 sf of floor area with a new floor system to create a second level in the former natatorium.

The project will also update non-compliant conditions including replacing the existing non-rated openings at the east side of the gymnasium with new 1-hr rated openings to separate the Group A gymnasium and Group B occupancies. In addition, a new smoke barrier will isolate the existing east side atrium from the new two-story lobby on the west side in the former natatorium.

A major renovation of the East portion of the building was completed in 2023. This portion of the building has a three-story atrium connecting floors 1, 2, and 3 with a convenience stair connecting all levels of the atrium. The East side renovation includes draft curtains and the required fire sprinkler head spacing at the floor openings between level 2 and level 3, as well as beam smoke detectors at the top of the atrium that are tied to the fire alarm system. This atrium configuration was approved through a previous appeal #24044 Item 2.

The existing atrium is outside of the scope of the renovation and is to remain as is per Chapter 34 (Existing Buildings) and the 2021 International Existing Building Code (IBEC) 403.1 (Alterations using the Prescriptive Compliance Path).

This appeal addresses the permitted by appeal three-story atrium with a convenience stair and an approved alternate means and methods for smoke control.

The HT building is located on a sloping site such that each of the 4 floors has at least one exit discharge directly to the exterior. Floors 1, 2, and 3, are connected to the atrium, with both floors 2 and 3 having two exits that discharge directly to the exterior. The provided exit discharges allows direct and effective egress to the exterior for the occupants. Occupants do not have to circulate down multiple levels to gain access to an exit discharge. The convenience stair, connecting levels 1, 2, and 3 in the atrium is not part of the required for egress path.

The existing building is fully sprinklered, Type II-A, non-combustible rated construction, and primarily a concrete structure. This inherently minimizes fire risk in comparison to other construction types and materials. The interior finish of walls and ceiling within the atrium space are minimum Class B to meet the intent of OSSC 404.8 and travel distance within the atrium space is no greater than 200 feet to meet the intent of OSSC 404.9.

The previous renovation, completed in 2023 reduced the size of openings between floors and added draft curtains and the required fire sprinkler head spacing at the floor openings between level 2 and level 3. This work included beam smoke detectors at the top of the atrium that are tied to the fire alarm system.

New 1-hr fire rated doors will replace existing non-compliant doors at the gymnasium which establishes compliant separation between Group A and Group B occupancies while preventing fire and smoke spread from the atrium to the 2-Story Gym. Additionally, smoke barriers will be added to prevent smoke spread from the atrium to the southwest portion of the building, the former natatorium.

The conversion of the natatorium (A-4 Occupancy) to classrooms (B Occupancy) reduces the overall occupant load of the building.

This appeal is intended to confirm that with the proposed west side scope of work and completion of the HT Building renovation, the previously permitted by appeal East side Atrium along with the proposed west side rated separations and smoke control, continues to meet the intent of OSSC 404 and Chapter 34.