(Amended by Ordinance Nos. 169427, 170997, 178831 and 180917, effective
May 26, 2007.) The definitions contained in this Section relate to seismic design requirements for existing buildings outlined in this Chapter.
A. ASCE 31 means the Seismic Evaluation of Existing Buildings ASCE/SEI 31-03 published by the American Society of Civil Engineers and the Structural Engineering Institute.
B. ASCE 31 Evaluation means the process of evaluating an existing building for the potential earthquake-related risk to human life posed by that building, or building component, and the documentation of that evaluation, performed and written according to the provisions of ASCE 31. ASCE 31 Evaluation is divided into two categories:
1. Non-essential facilities evaluation means a Tier 1 and a Deficiency-Only Tier 2 analysis to the Life Safety (LS) performance level as defined by ASCE 31 unless a complete Tier 2 analysis is required by ASCE 31.
2. Essential facilities evaluation means a Tier 2 analysis to the Immediate Occupancy (IO) performance level as defined by ASCE 31.
C. ASCE 31Improvement Standard means the Tier 1 and Tier 2 Life Safety Performance Level Criteria of ASCE 31.
D. ATC 20 means the 1989 Edition of the manual on “Procedures for Post Earthquake Safety Evaluation of Buildings” published by Applied Technology Council.
means the City of Portland
’s Bureau of Development Services.
F. Building Addition means an extension or increase in floor area or height of a building or structure.
G. Building Alteration means any change, addition or modification in construction.
H. Catastrophic Damage means damage to a building that causes an unsafe structural condition from fire, vehicle collision, explosion, or other events of similar nature.
I. Essential Facility has the same meaning as defined in the OSSC.
J. Fire and Life-safety for Existing Buildings (FLEx) Guide means a code guide published by the Bureau of Development Services, outlining alternative materials and methods of construction that are allowed for existing buildings in Portland.
FM 41 Agreement means a joint agreement between Portland Fire & Rescue, the Bureau of Development Services and a building owner to schedule improvements to the building following a determination of the fire and life safety hazards posed by the existing condition of the building as provided under Oregon
L. Live/Work Space means a combination working space and dwelling unit. A live/work space includes a room or suite of rooms on one or more floors designed for and occupied by not more than one family and including adequate working space reserved for the resident’s occupancy. A live/work space is individually equipped with an enclosed bathroom containing a lavatory, water closet, shower/and or bathtub and appropriate venting.
M. Net Floor Area means the entire area of a structurally independent building, including an occupied basement, measured from the inside of the permanent outer building walls, excluding any major vertical penetrations of the floor, such as elevator and mechanical shafts.
Oregon Structural Specialty Code (OSSC) means the provisions of the State of Oregon Structural Specialty Code
as adopted by Section 24.10.040 A.
O. Reinforced Masonry means masonry having both vertical and horizontal reinforcement as follows:
1. Vertical reinforcement of at least 0.20 in2 in cross-section at each corner or end, at each side of each opening, and at a maximum spacing of 4 feet throughout. One or two story buildings may have vertical reinforcing spaced at greater than 4 feet throughout provided that a rational engineering analysis is submitted which shows that existing reinforcing and spacing provides adequate resistance to all required design forces without net tension occurring in the wall.
2. Horizontal reinforcement of at least 0.20 in2 in cross-section at the top of the wall, at the top and bottom of wall openings, at structurally connected roof and floor openings, and at a maximum spacing of 10 feet throughout.
3. The sum of the areas of horizontal and vertical reinforcement shall be at least 0.0005 times the gross cross-sectional area of the element.
4. The minimum area of reinforcement in either direction shall not be less than 0.000175 times the gross cross-sectional area of the element.
P. Roof Covering Repair or Replacement means the installation of a new roof covering following the removal of an area of the building’s roof covering exceeding 50% or more of the total roof area within the previous five year period.
Q. Unreinforced Masonry (URM) means adobe, burned clay, concrete or sand-lime brick, hollow clay or concrete block, hollow clay tile, rubble and cut stone and unburned clay masonry that does not satisfy the definition of reinforced masonry as defined herein. Plain unreinforced concrete shall not be considered unreinforced masonry for the purpose of this Chapter.
R. Unreinforced Masonry Bearing Wall means a URM wall that provides vertical support for a floor or roof for which the total superimposed vertical load exceeds 200 pounds per lineal foot of wall.
S. Unreinforced Masonry Bearing Wall Building means a building that contains at least one URM bearing wall.