12 Resolution No. 20240502-094 — original pdf

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M E M O R A N D U M TO: Mayor and Council Members THROUGH: Veronica Briseño, Assistant City Manager FROM: José G. Roig, Development Services Director Chief Joel Baker, Aus�n Fire Chief Chief Robert Luckritz, EMS Chief, Aus�n Travis County EMS DATE: June 26, 2024 SUBJECT: Resolu�on No. 20240502-094 Staff Update - Single Stairway Provisions for Mul�family Developments Up to Five-Stories We want to provide all of you with a mul�-departmental recommenda�on on Resolu�on No. 20240502-094 which proposes an amendment to the 2024 Interna�onal Building Code (IBC) allowing a single stairway for mul�family developments up to five stories. Technical code and first responder experts from the Development Services Department (DSD), Aus�n Fire Department (AFD), and Aus�n/Travis County Emergency Medical Services (ATCEMS) reviewed Aus�n’s single stairway amendment and found significant poten�al safety risks to occupants and first responders were we to amend the Code. As a result, staff recommends that the City of Aus�n con�nue to allow the model na�onal codes to set minimum standards for construc�on in Aus�n, thereby maintaining two means of egress for mul�family developments. Safety Concerns Construc�ng a single stairway --as opposed to two separate stairways-- for a five-story building poses escape hazards for occupants during fire, ac�ve shooter, severe weather, or large-scale emergencies. The following points highlight primary safety concerns: • Occupant Risk Considera�ons – Fire-loss data, some�mes cited by proponents of single stairway design, suggests that such an approach poses a low risk to occupants. While the probability of a fire is low, the consequences of a fire with a single stairway design make this an inherent risk. The na�onal standard set in the model code manda�ng two staircases reflects the increased likelihood of significant injury and mass casual�es in limi�ng occupants to a single exit in the event of a fire or other emergency. • Subject Mater Expert Findings – A na�onal proposal to permit mid-rise buildings to be served by a single exit stairway was reviewed and overwhelmingly rejected by the Interna�onal Code Page 1 of 4 Council (ICC) Technical Commitee, ci�ng tes�mony from many na�onal safety experts about the dangers it would pose to occupants and first responders. • Hindered Evacua�on Tac�cs – AFD employs evacua�on tac�cs by designa�ng one stairwell for evacua�on and the second stairwell for firefigh�ng opera�ons. Elimina�ng a stairwell may lead to unsafe exposure of fire condi�ons to occupants and cause counterflow and conges�on with occupants and firefighters atemp�ng to use the same stairs for both egress and ingress during an emergency. o Delayed access by firefighters allows an emergency condi�on to worsen, and delayed evacua�on puts occupants at risk. This is further complicated when there are mobility impaired individuals being evacuated, due to addi�onal �me needed to traverse stairs. • Lack of Equipment – Unlike the few ci�es that permit a single stairway in a mid-rise residen�al building, AFD’s ability to perform rescue from high windows is limited by a rela�vely small number of ladder trucks. o The 13 ladder trucks in Aus�n are spread over a wide geographic area that includes two trucks in or adjacent to Williamson County and one in the Hays/Travis County border. Both the number of Aus�n’s ladder trucks and their geographic distribu�on means AFD cannot ensure adequate response �me. • Insufficient and Aging Water Infrastructure in Residen�al Areas –Changes in our land development code will allow small, mul�family proper�es up to five stories to be developed in residen�al areas that may not have sufficient water flow and pressure to suppress a fire in a five-story building. • Obstructed Emergency Medical Services – A single stairway has the poten�al to create botlenecks that may result in delayed services to pa�ents or injured first responders. A need for a stretcher-accessible elevator in buildings with a single stair may be necessary if a single stair code amendment is passed. • Evacua�on In Ac�ve Shooter Situa�ons – The best chances for survival in an ac�ve shooter situa�on require occupants to exit a building immediately if possible. The U.S. Department of Homeland Security states that facili�es should have at least two evacua�on routes. Elimina�ng a stairway reduces paths of evacua�on for occupants atemp�ng to flee a life-threatening emergency. Comparison of Seatle, WA, New York, NY and Aus�n, TX New York and Seatle are cited as ci�es that have adopted single-stairway regula�ons. The following table shows the popula�on density per square mile for each of the three ci�es. Both New York and Seatle outpace Aus�n’s popula�on density while Aus�n has the most land area. Based on a calcula�on of Aus�n’s proper popula�on of 983,126 and a two percent annual growth, it would take Aus�n 55 years to meet Seatle's current density. Aus�n is not facing the same popula�on density challenges as Seatle and New York. This allows Aus�n �me to seek solu�ons for more middle-scale density with fewer life safety implica�ons. Page 2 of 4  City Seatle, WA New York, NY Aus�n, TX 9,024 Popula�on Density (Persons/Square Mile) 2024 Popula�on (Proper) Land Area (Square Miles) Source: https://worldpopulationreview.com/us-cities 757,992 84 300 26,397 7,931,147 3,012 983,126 326 The table below details the requirements for mul�family developments with a single stair by City. If the code amendment is passed, the future requirements for Aus�n are detailed in the last column. Seatle, WA New York, NY Aus�n, TX City Height Light Wood Framing Sprinklers Non-Stair Fire Fighter Access 6 Stories Allowed 6 Stories Not Allowed 1 NFPA 13 2 One opening per floor by aerial 3 NFPA 13R 2 One opening per floor by aerial 5 stories (as allowable per construction type 2021 IBC) Not Allowed NFPA 13 - Evacua�on Elevator 4 - One opening per floor by aerial Required Required Required Required Not required Enclosed Stairway Sha� Ven�lated Pressurized Stair Max Floor Size 5 2,000 sf 1 New York requires non-combus�ble construc�on which improves the protec�on of buildings and their occupants from fire. 2 While Seatle does not require non-combus�ble construc�on, they do require a more robust sprinkler system (NFPA 13) as opposed to New York’s residen�al sprinkler design system. 3 Both Seatle and New York require one opening per floor to allow for aerial rescues. Aerial rescues are dependent on sufficient ladder truck availability. 4 Aus�n proposes adding occupant evacua�on elevators due to insufficient inventory of ladder trucks. 5 Maximum floor size is the travel distance to a stairwell. Required 4 Units 4 Units Impact on Construc�on Costs and Affordability The implementa�on of provisions for a single stairway may result in higher construc�on costs to compensate for the loss of egress stairs. Examples of layered protec�on in buildings to ensure safety if this amendment is passed include: • Non-combus�ble construc�on • Pressurized stair & elevator sha� • Back-up power for occupant evacua�on elevator A shi� in staircase design requirements is unlikely to have a measurable impact on the number of housing units built. It is not guaranteed that addi�onal units constructed would be offered at a price that would improve housing affordability, since the developer would not be constrained with respect to pricing for rent or sale. Page 3 of 4  Addi�onally, this resolu�on specifies a single stairway for mul�family developments up to five stories, however, the number of occupants is not limited. This means an unlimited number of occupants may be served by a single exit. Many of these proposed mul�family developments serve our more vulnerable popula�ons; our goal is to con�nue to promote equitable access for those with mobility challenges as well as protect the standard of living and life safety to all occupants. If you have any ques�ons, please contact José G. Roig, Development Services Director, at 512-974- 1605 or via email at Jose.Roig@aus�ntexas.gov. cc: T.C. Broadnax, City Manager Brenda de la Garza, Assistant Director, Development Services Todd Wilcox, Building Official, Development Services Chief Andre De La Reza, Assistant Chief, Aus�n Fire Chief Rob Vires, Chief of Staff, Aus�n Fire Chief Stephen Truesdell, Division Chief, Aus�n Fire Chief Wesley Hopkins, Chief of Staff, Aus�n Travis County EMS Page 4 of 4