Torrance Municipal Code Art. 1 Mandatory Seismic Strengthening Provisions for Existing Wood Frame…

815.1.010 PURPOSE.

The provisions of this Chapter are intended to promote the public welfare and safety by reducing the risk of death or injury that may result from the effects of earthquakes on existing wood-framed multi-story buildings with Soft, Weak or Open-Front Walls. Generally, this type of structure consists of partial tuck-under parking on the first-floor level with single or multifamily living space in the floors above. In past earthquakes, many of these types of structures have performed poorly and collapsed causing loss of life, personal injury, and substantial property damage.

This Chapter creates minimum standards intended to reduce the risk of collapse and improve the performance of these buildings during earthquakes and reduce, but not necessarily prevent, the loss of life, injury, or damage to property. The requirement for compliance with these standards does not preclude the utilization, at the Building Owner’s option, of a more extensive strengthening method that might further prevent or limit loss of life, injury, or building damage.

815.1.020 SCOPE AND APPLICABILITY.

The provisions of this Chapter shall apply to all existing buildings of wood-frame construction, or wood-frame portions thereof, where:

a) The existing building is determined by the Building Official to have been built under building code standards enacted before the 1976 Uniform Building Code with local amendments adopted on August 1, 1978, and,

b) The Ground Floor or basement portion of the structure contains parking or other similar open floor space that causes Soft, Weak, Open-Front Wall Lines, or the majority of the Ground Floor or basement portion of the structure contains an open floor space, and there exists one or more stories above.

Exceptions:

The provisions of this chapter shall not apply to single family residences or multiple-family residential buildings containing three or less units.

Notwithstanding any provision of the Building Code, compliance with this Chapter shall not require existing electrical, plumbing, mechanical or fire-safety systems to be altered to comply with the current Building Code unless they constitute a hazard to life or property as determined by the Building Official.

Mitigation of existing geologic site hazards such as liquefiable soil, fault rupture, or landslide is not required for compliance with this Chapter.

815.1.030 DEFINITIONS.

Notwithstanding the applicable definitions, symbols, and notations in the Building Code, the following definitions shall apply for the purposes of this Chapter:

a) Building Code is the current Building Code of the City of Torrance.

b) Cripple Wall is a wood-framed stud wall extending from the top of the foundation wall to the underside of the lowest floor framing.

c) Design Criteria is a document that outlines the design professional’s alternative analysis or Retrofit approach and methodology to satisfy the design intent and performance objective of the Ordinance. This document is intended to be used when the code and seismic Ordinance language does not address the proposed analysis or Retrofit approach or methodology.

d) Ground Floor is any floor within the wood-frame portion of a building whose elevation is immediately accessible from an adjacent grade by vehicles or pedestrians. The ground floor portion of the structure does not include any floor that is completely below adjacent grades.

e) Historical Building is any building designated, or currently in the process of being designated, as a "qualified historical building" as defined in Part 8, Title 24 of the California Code of Regulations.

f) Open-Front Wall Line is an exterior Wall Line, without vertical elements of the lateral force-resisting system, which requires tributary seismic forces to be resisted by diaphragm rotation or contains an excessive cantilever beyond parallel lines of shear walls. Diaphragms that cantilever more than 25 percent of the distance between lines of lateral force resisting elements from which the diaphragm cantilevers shall be considered excessive. Diaphragm cantilevers or exterior balconies of 6 feet or less in width shall not be considered excessive cantilevers.

g) Owner or Building Owner is the individual(s), agent, firm, corporation, or entity having legal possession, equitable interest in the property, or rights to sanction evaluation or Retrofit of a building.

h) Retrofit is an improvement of the lateral force resisting system by alteration of existing structural elements or addition of new structural elements.

i) Seismic Design Guidelines are framework guidelines developed by the Building Official which are intended to calibrate, delineate, and detail technical requirements to be used for the retrofitting of buildings subject to this Chapter.

j) Soft Wall Line is a deficiency in a Wall Line in which the lateral stiffness is less than what is required by story drift limitations and deformation compatibility requirements of this Chapter. In lieu of the engineering analysis required by this Chapter to determine whether a wall line’s lateral stiffness is less than the aforementioned story drift limitations and deformation compatibility requirements, a Soft Wall Line deficiency may be defined as a Wall Line in a Story where the wall stiffness is less than 70 percent of the stiffness of the exterior wall above for the direction under consideration.

k) Story is as defined in the Building Code, but includes any basement or under-floor space of a building with Cripple Walls exceeding four feet in height.

l) Story Strength is the total strength of all seismic-resisting elements sharing the same Story shear in the direction under consideration.

m) Wall Line is any length of a wall along a principal axis of the building used to provide resistance to lateral loads.

n) Weak Wall Line is a deficiency of a Wall Line at the Ground Floor in which the wall strength is less than 80 percent of the strength of the wall above in the direction under consideration or is an exterior wall where the majority of the Ground Floor or basement portion of the structure contains an open floor space and the Ground Floor Story Strength is less than 80 percent of the Story Strength above.

o) Substantial Evidence means more than a mere scintilla of evidence. Specifically, that there is such relevant evidence that a reasonable mind would accept it is adequate to support a conclusion, considering the totality of the evidence as a whole.

p) Good Cause means adequate or substantial grounds or reason to take certain action, or fail to take certain action required by this Chapter. (For example, the inability to secure funding for seismic retrofit repairs within the required time period, despite substantial evidence that a building owner has made best efforts to do so; or the inability to secure a contractor to perform seismic retrofit repairs within the required time period, despite substantial evidence that a building owner has made best efforts to do so, or other similar circumstances.)

815.1.040 COMPLIANCE REQUIREMENTS.

The Owner of each building within the scope of this Chapter shall cause an investigation of the existing construction and a structural analysis to be performed on the building by a Licensed Design Professional in the State of California. If the building does not meet the minimum standards specified in this Chapter, the Owner shall cause it to be structurally altered to conform to such standards.

Each building within the scope of this Chapter, which has been analyzed to demonstrate compliance or has been structurally altered to comply with the minimum standards in this Chapter, shall be maintained in conformity with the requirements of this Chapter, in effect at the time of such analysis or structural alteration.

Notwithstanding any other provisions of this Code to the contrary, a building that is found to be within the scope of this Chapter and is not brought into compliance in the time frame indicated in Table A, may be declared unsafe and subject to the requirements of Section 116 of the California Building Code.

815.1.050 TIME PERIOD FOR COMPLIANCE/PRIORITY DESIGNATION.

a) Screening Report. Within the time limits allowed in Table A, the Owner of any building subject to the provisions of this Chapter shall submit a screening report to the Building and Safety Division. The report shall demonstrate whether the structure conforms to the earthquake design provisions contained in this Chapter. Minimum form requirements shall be as specified by the Building Official.

b) Plan, Permits and Construction. If the screening report concludes the structure does not comply with the provisions of this Chapter, the structure shall be strengthened to comply with the standards of this Chapter within the time periods shown in Table A. Minimum plan requirements shall be as specified by the Building Official.

TABLE A TIME PERIOD FOR COMPLIANCE

c) Priority Designations. The Building Official shall prioritize enforcement of this Chapter as defined in Table B.

TABLE B PRIORITY DESIGNATION

815.1.060 ADMINISTRATION.

a) Issuance of Order. The Building Official shall, in accordance with the priorities set forth in Table B, issue an order as provided in this Section to the Owner of each building that is expected to be within the scope of this Chapter.

b) Contents of Order. The order shall be in writing and shall be served by certified or registered mail to the Owner as shown on the last equalized Los Angeles County assessment roll of the building. The order shall specify that the building has been determined by the Building Official to be within the scope of this Chapter and, therefore, is required to meet the standards of this Chapter.

c) Service of Order. Proper service of a notice shall be by registered or certified mail. It shall be deemed a reasonable effort has been made to serve such notice when registered or certified letters have been mailed to the address of the interested party as shown on the official record. The designated period within which the Owner or person in charge is required to comply with such notice shall begin as of the date the Owner or person in charge receives such notice by personal service or certified mail.

d) Failure to Receive Order. Failure of any Owner, party concerned or other person to receive such notice shall not affect the validity of any proceedings taken thereunder.

e) Appeal from Order. The owner of any building may appeal any decision or order issued by the Building Official or his designee pursuant to this Chapter, including, but not limited to, the initial determination that a building is within the scope of the City of Torrance Seismic Retrofit Laws or the conclusion that a building must be retrofitted, to the City Manager or their designee. Any such appeal shall be filed with the City Manager within 30 days of the date of the Building Official’s or their designee’s order or decision. Any such appeal shall be decided by the City Manager no later than ninety days after filing. The filing of an appeal would stay the underlying order or decision and the associated time limits. Should the appeal be denied by the City Manager or their designee, the initial time limits shall be restored, unless the City Manager or their designee authorizes alternate time limits. The City Manager’s or their designee’s decision shall be final except for judicial review.

f) Extensions. The Building Owner may request an extension to the time period for compliance set forth in Table A of section 815.1.050. An application for extension may only be filed after the Owner has submitted a Screening Report to the City and the Retrofit Plans have been approved by the City. The Building Owner has the burden of proof to establish with substantial evidence that good cause for the extension exists. The Building Owner must also provide a new proposed schedule for compliance, and plan to comply with the provisions of this chapter during that timeframe. Upon good cause shown, the Building Official may approve, approve with modifications, or deny a request for an extension, commensurate with the justification for the extension.

g) Recordation. Once a building that was determined to be within the scope of this Article has failed to comply with the requirements of this Chapter within the time limits provided in Table A, the Building Official shall record in the office of the Los Angeles County recorder a certificate stating that the subject building is within the scope of this Article and requires seismic retrofit. The Certificate shall also state that the Owner thereof has been notified of the need to retrofit the building. Once the building has been retrofitted to comply with this Chapter, the Building Official shall record a Certificate indicating that the subject building no longer is in violation of this Chapter.

h) The Building Official may promulgate implementing regulations and policies consistent with this Chapter.

815.1.070 OCCUPANCY AND TENANT ADVISORY.

Notification to Tenants and Occupants. The Owner shall notify in writing all current and prospective residential and non-residential tenants, subtenants, lessees, sub lessees, or any other person(s) entitled to the use and/or occupancy of the building of a proposed project submitted pursuant to this Chapter. The notice shall include the information for the project, as determined by the City, including the scope of work, expected duration, and contact information for a representative of the contractor. The form of notice shall be supplied by the Community Development Department and Building and Safety Division.

815.1.080 HISTORICAL BUILDINGS.

Historical Buildings shall comply with the California Historical Building Code and the provisions of this Chapter. Modifications to the standards set forth in this Chapter may be permitted when such modifications are consistent with the provision of the California Historical Building Code. Such modifications shall be clearly specified in the screening report.

815.1.090 ENGINEERING ANALYSIS AND DESIGN.

a) Scope of Analysis. This Chapter requires the alteration, repair, replacement or addition of structural elements and their connections to meet the strength and stiffness in conformance with the Building Code except as modified herein. The lateral-load-path analysis shall include the resisting elements and connections from the wood diaphragm immediately above any Soft, Weak or Open-Front Wall lines to and including the foundation. Stories above the Weak Wall Line shall be considered in the analysis but need not be modified. The Engineer shall investigate existing conditions as applicable for the required analysis, including performing initial material testing and verification of existing conditions.

b) Design Base Shear and Design Parameters. The design force in a given direction shall not be less than 75% of that derived from the Base Shear as determined from the seismic provisions of ASCE 7 and design provisions as specified by the current Seismic Design Guidelines. The structure shall be analyzed and/or strengthened in order to mitigate the Weak and/or Soft Wall Line deficiencies defined in Section 815.1.030.

Exception: Alternatively, the structure may be retrofitted per Appendix A4 of the California Existing Building Code, provided the entire Story is analyzed and/or strengthened in order to mitigate the Weak and/or Soft Wall Line deficiencies defined in Section 815.1.030.

c) Lateral Vertical Systems. Strengthening systems with concrete walls or masonry walls, or steel braced frames shall not be permitted unless a full building analysis considering diaphragm stiffness and torsional behavior is performed.

d) Horizontal Structural Irregularities in Buildings with Three or More Stories. Structures with three or more stories having horizontal structural irregularities of either type 2, 3, 4, or 5 listed in ASCE 7, "Horizontal Structural Irregularities," shall be altered to meet the additional requirements of those sections referenced in the table for the Weak, Soft or Open-Front Wall lines being considered.

e) Alternate Analysis, Base Shear and Design Parameters. The Building Official may approve alternate analysis and/or design methodologies that meet the same performance intent as those prescribed by this Chapter and that achieve the objectives established by this Chapter. A Design Criteria shall be submitted to the City for review and approval prior to submission of plans. Peer review shall be required when advanced systems, such as damped systems, are utilized.

f) Additional Anchorage Requirements for Buildings on Hillsides. Where any portion of a building within the scope of this Chapter is constructed on or into a slope steeper than one-unit vertical in three units horizontal (33-percent slope), the lateral-force-resisting system, at and below the base level diaphragm, shall also be analyzed for the effects of concentrated lateral loads caused at the building base from the hillside conditions and comply with the provisions of the Building Code.

g) Story Drift Limitations. The calculated story drift for each retrofitted Story shall meet the requirements of the current Seismic Design Guidelines.

h) Deflection Compatibility. The design of the new retrofit elements shall be compatible with the existing structural elements.

i) Ties, Continuity and Collectors. All parts of the structure included in the scope of analysis shall be interconnected and the connection shall be capable of resisting the seismic force created by the parts being connected as required per the Building Code.

j) Foundations. Foundations shall be designed in accordance with the Seismic Design Guidelines. New foundation elements shall be capable of transferring the loads to the supporting soil without negatively impacting the existing foundations.

k) Pole Foundations. The effects of rotation and soil stiffness shall be included in the analysis where lateral loads are resisted by vertical elements whose required depth of embedment is determined by pole formulas. The design of the pole foundations shall be based on an approved geotechnical investigation conducted in accordance with approved geotechnical engineering reports.

815.1.100 INFORMATION REQUIRED ON PLANS.

a) General. In addition to administrative items, the plans and specifications required by the Building Official shall be of sufficient clarity to indicate the nature, design methodology, and extent of the proposed work and to show in detail that it will conform to the provisions of this Chapter and the Building Code.

b) Licensed Design Professional Statement. The Licensed Design Professional responsible for the design of the retrofit shall provide the following statements on the approved plans:

I am responsible for designing this building’s seismic strengthening in compliance with the minimum standards of the Mandatory Seismic Strengthening Provisions For Existing Wood Frame Buildings With Soft, Weak or Open-Front Walls (Division 8, Chapter 15, Article 1 of the Torrance Municipal Code).

c) Owner or Owner’s Representative Statement. Unless the entire building has been retrofitted to meet the full intent of the current Building Code, the Owner shall provide and sign the following statement on the cover of the drawings:

I understand the seismic evaluation and strengthening performed under this project is limited to that specified in the Mandatory Seismic Strengthening Provisions For Existing Wood Frame Buildings With Soft, Weak or Open-Front Walls (Division 8, Chapter 15, Article 1 of the Torrance Municipal Code) which is intended to reduce the risk under a seismic event. I understand the full building has not been evaluated nor strengthened for other potential structural deficiencies that may cause a life safety concern, injury, or property damage risk under a seismic event.

d) Quality Control and Assurance Requirements. General notes shall show the requirements for material testing, special inspection, structural observation and the proper installation of newly added materials.

815.1.110 QUALITY ASSURANCE.

a) Structural Observation. Structural observation in accordance with the Building Code is required, regardless of seismic design category, height or other conditions. Structural observation shall include visual observation of work for conformance to the approved construction documents and confirmation of existing conditions assumed during design.

b) Testing and Inspection. Structural testing and inspection for new construction materials, submittals, reports, and certificates of compliance shall be in accordance with Building Code and the Seismic Design Guidelines.

815.1.120 VIOLATION/PENALTY.

a) Violation. Notwithstanding any other provisions of this Code to the contrary, it shall be unlawful for any person, firm or corporation, to own, use, occupy or maintain any building or structure or portion thereof, or cause the same to be done, contrary to, or in violation of, any of the provisions of this code.

b) Penalty:

(1) Any person who violates any provision of this Article is guilty of a misdemeanor unless the violation is cited or charged by the City or the City Attorney and/or reduced to an infraction.

(2) Each such person charged with a misdemeanor shall be guilty of a separate offense for each and every day or portion thereof during which any violation of any of the provisions of this code is committed, continued or permitted, and upon conviction of any such violation such person shall be punishable by a fine of not more than $1,000 (one thousand dollars), or by imprisonment for not more than six months, or by both such fine and imprisonment. The provisions of this section are in addition to and independent of any other sanctions, penalties, or costs which are or may be imposed for a violation of any of the provisions of this code;

(3) Any violations of this Article may result in civil, criminal and/or administrative enforcement actions.

c) Recordation of violation.

(1) General. The Building Official may record a notice with the County Recorder’s Office that a property, building or structure, or any part thereof, is in violation of any provision of this code provided that the provisions of this section are complied with. The remedy provided by this section is cumulative to any other enforcement actions permitted by this code.

(2) Recordation. If (A) the Building Official determines that any property, building, or structure, or any part thereof is in violation of any provision of this code; and if (B) the Building Official gives written notice as specified below of said violation; then the Building Official may have sole discretion to, at any time thereafter, record with the County Recorder’s Office a notice that the property and/or any building or structure located thereon is in violation of this code.

(3) Notice. The written notice given pursuant to this Section shall indicate:

a) The nature of the violation(s); and

b) That if the violation is not remedied to the satisfaction of the Building Official, the Building Official may, at any time thereafter, record with the County Recorder’s Office a notice that the property and/or any building or structure located thereon is in violation of this code. The notice shall be posted on the property and shall be mailed to the Owner of the property as indicated on the last equalized County Assessment roll. The mailed notice may be by registered, certified, or first-class mail.

(4) Rescission. Any person who desires to have recorded a notice rescinding the notice of violation must first obtain the necessary approvals and permit(s) to correct the violation. Once the Building Official determines that the work covered by such permit(s) has been satisfactorily completed, the Building Official may record a notice rescinding the prior notice of violation.

Following the recordation of the notice of violation the Building Official is not required to make any inspection or review of the premises to determine the continued existence of the cited violation. It is the responsibility of the property Owner, occupant or other similarly interested private party to comply with the above provisions.

d) Costs. Any person that has violated any provision of this code shall be responsible for the costs of any and all Code Enforcement actions taken by the Building Official in response to such violations. These costs shall be based on the amounts specified by the current fee schedule.

815.1.130 APPLICABILITY.

a) Internal conflict. Where there is a conflict between a general requirement and a specific requirement, the specific requirement shall be applicable. Where, in any specific case, different Sections of this Chapter specify different materials, methods of construction, or other requirements, the most restrictive shall govern.

b) Other laws. The provisions of this code shall not be deemed to nullify any provisions of local, state, or federal law.

c) Codes and references. The provisions of the codes and standards referenced in this code shall be considered part of the requirements of this Chapter to the prescribed extent of each such reference. Where there are conflicts between the provisions of this Chapter and the provisions of any referenced code or standard, the provisions of this Chapter shall apply.