Appeal 33707

Portland Title 24 section 24.85 Seismic Design Requirements for Existing Buildings

Portland City Code 24.85.040 Change of Occupancy or Use
A. Occupancy Change to a Higher Relative Hazard Classification. An occupancy change to a higher relative hazard classification will require seismic improvements based upon the factors of changes in the net floor area and the occupant load increases as indicated in Table 24.85-B below. All improvements to either the OSSC or ASCE 41 improvement standard shall be made such that the entire building conforms to the appropriate standard indicated in Table 24.85-B Where more than 1/3rd of the building area has a change of occupancy from R-3 (hazard 1) to R-2 (hazard 4), ASCE 41 BPOE or equivalent seismic improvement standard shall be followed.
Portland City Code 24.85.065 Seismic Strengthening of Unreinforced Masonry Bearing Wall Buildings When any building alterations or repairs occur at an Unreinforced Masonry Bearing Wall Building, all seismic hazards shall be mitigated as set forth in Subsections 24.85.065 A. and B.

The intent of this appeal is to allow change of occupancy without triggering a full seismic upgrade to the entire building. This appeal requests that this building be approved for a change of occupancy of the entire 1st and 2nd floor from a R-3 baseline occupancy (hazard 1) (9-18-02 #02-140127-CO) to a R-2 occupancy (hazard 4) and a change of occupancy in a partial area of basement (1,590 s.f) from A-3 baseline occupancy – previously Model Engineers Club (9-18-02 #02-140127-CO) to a R-2 occupancy (hazard 4). The remaining basement area to remain as a storage occupancy.

The 5500 SE Belmont building is a 2-story commercial building (w/additional basement), III-B (unreinforced masonry and heavy timber construction), non-sprinklered , RM-1 zoning (w/historical overlay), with a baseline occupancy of R-3 (live/work unit), A-3 and S occupancy (9-18-02 #02-140127-CO), and a total building area of roughly 9,882 s.f. The building was constructed in 1914 for the Pacific Telephone & Telegraph Company (#45475) and held vital city infrastructure. In 1953 they sold the building, and it was converted to the Mt. Tabor Mason’s Lodge (#327472). In 1973 the basement was rented to the Mount Hood Model Engineers (club w/viewing days to the public). Tim and Patty Merrill bought the building in 1996 for use as their personal residence and for occupancy of the Merrill architectural firm – Live/work unit. (9-16-01 #01-153060-CO), (9-18-02 #02-140127-CO (Baseline occupancy before Portland City Code Chapter 24.85 seismic design requirements for existing buildings permitted as R-3 (Based on 2022 Oregon Structural Specialty Code a live/work unit would be considered a R-2 occupancy per this latest code, A-3 (Model Engineers Club – basement = 1,590 s.f.) and S (remaining basement area), and (5-13-12 #12-122232-CO + Big board appeal case no: B-001 Partial change of use to residential area without sprinklers: Granted provided hard-wired residential-style smoke alarms, connected to the building power supply and monitored off-site). The building owner, Todd Moore purchased the building with the listing stating - one main living unit on the entire top floor, two residential units and one small office on the main floor (1st) which assumed a R-2 occupancy with being over 2-units. The discovery through looking at public records have found that it was never permitted for a R-2 occupancy. We are hopeful that the board will understand and appreciate the dilemma that the owner is in. The building owner is proposing these future modifications to accommodate the safety concerns and chart a path that meets the community safety objectives while making it feasible to make improvements happen to the building. It would not be economically feasible to upgrade the entire building seismically. (See supplemental Drawings by Crux Architecture)

1. Fire sprinkler system: Any new units would be required to install a new sprinkler system (NFP 13R – R-2 classification) . The owner would upgrade to a full NFPA 13 sprinkler system throughout the entire building .
2. Fire Alarm System: Provide a fire alarm system throughout the entire building per NFPA 72 – 2025 National Fire Alarm and Signaling Code.
3. Seismic upgrades: Provide out of plane floor to wall ties at approximately 4 feet on center and provide out of plane roof to wall ties at approximately 4 feet on center. We will execute a parapet seismic retrofit during the next re-roof.
4. Means of egress: a. Provide a secondary direct means of egress out of the basement b. Provide (2) additional egress doors from the 1st floor directly out of units. C. The 2nd floor would have an exterior stairs added to replace the removal of existing stairs exiting out of the 1st floor.

Our understanding of the Portland seismic code requirements and its application is that the code language was initiated to encourage seismic upgrade of buildings when the owner is looking to make improvements. This approach marries the economic concerns with the safety concerns and charts a path that meets the community safety objectives and owners economic viability
A. Improved safety of building, based on life and risk. For a building of this size with 2 stories, the proposed full NFPA 13 sprinkler system, proposed fire alarm system , and the proposed seismic upgrades we believe will drastically improve the safety, based on life and risk of the building and its occupants.
B. Decrease in total occupants based on the history of the building and baseline (9-18-02 #02-140127-CO): (1914) The Pacific Telephone & Telegraph Company (44 total occupants), (1953) Masonic Lodge (246 total occupants), (2001 Baseline) Merril Residence and Merrill Architecture office (111 total occupants). The proposed 7-units for the Moore Residence (49 total occupants) is a 44% decrease of total occupants from the baseline (111 total occupants).
C. 2022 Oregon Structural Specialty Code Chapter 34 – Existing Buildings 3405.6 change of occupancy – 3405.6.1 Subject to the approval of the building official, changes of occupancy shall be permitted without complying with all of the requirements of this code for the new occupancy, provided that the new occupancy is not more hazardous, based on life and risk, than the existing occupancy. We believe that the new is not more hazardous, based on life and risk based on reduction of total occupants and reduction of means of egress travel distance out of the building.
D. Means of Egress (travel distance from each floor of the building) Basement: Per baseline (9-18-02 #02-140127-CO) greatest travel distance for egress – 78’-3”, proposed greatest travel distance for egress – 68’-9’ (reduction of 9%)
1st floor: Per baseline (9-18-02 #02-140127-CO) greatest travel distance for egress – 46’-6”, proposed greatest travel distance for egress – 39’-9’ (reduction of 8%)
2nd floor: Per baseline (9-18-02 #02-140127-CO) greatest travel distance for egress – 67’-9”, proposed greatest travel distance for egress – 71’-6’ (increase of 5%)
E. Additional housing units
The site is roughly 10,814 s.f. within a Residential Multi-Dwelling (w/historical overlay) zoning. Per zoning code a minimum density of 1 unit per 2,500 s.f. of site area = 5 units required. A provision allows a reduction of 2 units with an existing building. This gives a total of 3 units required. Adding more units will help Portland’s overall goal of providing more housing units within RM-1 zoning.
We are hopeful that the board will understand and appreciate the dilemma that the owners are and grant this appeal to reverse the sequence of construction and approval. (See supplemental Drawings by Crux Architecture)

2022 Oregon Structural Specialty Code - Allowable area of openings per story (705.8)

Per Table 705.8 Maximum area of exterior wall openings based on fire separation distance and degree of opening protection. O to less than 3’ - allowable area of openings not permitted.

We are requesting allowance of existing openings to be maintained without requiring any modification or rating to a proposed replacement window system.

The East façade has original windows from 1914 for the Pacific Telephone & Telegraph Company (#45475). The building owner is proposing replacing the deteriorated existing windows on the 1st and 2nd floor with new windows within the existing openings (non-rated)

1. Fire sprinkler system: The owner would upgrade to a full NFPA 13 sprinkler system throughout the entire building . In addition would provide a sprinkler head above each opening at interior on the 1st and 2nd floor at all East windows.
2. Reduction of number of openings and area: Remove basement windows on East Side and infill to match exterior wall rating per table 601 (type III-B) of 2 hour rating. This reduces opening area on the East side by a total of 18 s.f. (6 s.f. per (3) windows)
3. Replace exterior windows on 1st and 2nd: Replace existing windows on the 1st and 2nd floor within existing openings and window design to maintain historical architectural aesthetic of the building. Wall area (1,400 s.f.) divided by the area of openings on the 1st and 2nd floor (165 s.f.) = 9% of wall area. No new openings on East side.

Historically the East side building setback has been stated as being 4’-1” (#22-126904-000-00-CO). This would allow unprotected openings in a sprinklered building for up to 15% of area. The owner has found through a recent site survey with CH Survey Inc that the East setback is actually 2’-2”. The adjacent site to the East has a driveway next to the property line with the house setback. We feel that in order to maintain the historical architectural significance of the building that the windows need to be maintained on the 1st and 2nd floor of the East façade. Additionally by providing sprinkler heads over the windows and upgrading to a full 13 fire sprinkler system there would be significant improvement to life and safety to the building and its occupants.