The U.S. Resiliency Council (USRC) and the Building Rating System

The notion that there is a disconnect between the anticipated performance of buildings in a major earthquake, and what the public understands or expects, is not new. Bridging this communication gap has been discussed in a number of different forums, including U.S.-Japan workshops (ATC-JSCA, 2010, 2014). The idea of a building rating system has arisen on a national level in the NEHRP Workshop on Meeting the Challenges of Existing Buildings (ATC-71, 2008), Prioritized Research for Reducing the Seismic Hazards of Existing Buildings (ATC-73, 2007), and Grand Challenges in Earthquake Engineering Research, A Community Workshop Report (National Academies, 2011). Input on creating such a rating system was obtained in the FEMA-funded Workshop on a Rating System for the Earthquake Performance of Buildings (ATC-71-2, 2011). The thought was that if the public could be made more aware of their potential seismic risk, they could be expected to make better-informed decisions on owning and leasing properties, and market forces would eventually drive the building design, management, and procurement process into more resilient seismic design. Seismic performance assessment techniques have reached level of sophistication and maturity that we now feel capable of distilling complex measures of performance into meaningful sound-bite information that is expected to be useful to owners, developers, tenants, lenders, and insurers in their building procurement transactions. Efforts to develop a building rating system have included many technical and philosophical challenges, but the U.S. Resiliency Council® (USRC) has formed a diverse coalition of technical organizations, engineering firms, individuals, industry supporters, and government agencies to develop a consensus-based approach to solving these challenges. This paper describes the need for a building rating system, the potential users, the information it provides and the measures that will be used to maintain the long term credibility of the system. Another paper in this session (Mayes and Reis, 2015) covers the goals and objectives, organization, and founding principles of the USRC. Two additional papers describe the two evaluation methodologies (ASCE 31/41 translation, Hohbach et.al. 2015; and FEMA P58, Haselton et.al 2015) that will initially be used to determine the earthquake ratings. THE NEED FOR A BUILDING RATING SYSTEM With current assessment tools such as FEMA 154, Rapid Visual Screening of Buildings for Potential Seismic Hazards: A Handbook, Second Edition (FEMA, 2002); ASCE 31, Seismic Evaluation of Existing Buildings (ASCE, 2003); ASCE 41, Seismic Rehabilitation of Existing Buildings (ASCE, 2014); and FEMA P-58 nextgeneration assessment procedures newly released, the concept of a new system to rate the performance of buildings would seem unnecessary, or at least redundant. Although they would be key inputs to a building rating system, currently available tools alone cannot do what a comprehensive rating system would do:  Communicate levels of performance to broad-based, non-technical audiences  Address new and existing buildings in a consistent context  Correct popular misconceptions about expected building performance  Provide multiple measures of performance to suit different decision-making needs  Better enable relative comparisons of performance between different buildings  Provide a context for public policy decisions and market forces to encourage and reward better performing designs Currently available tools have reached level of sophistication and maturity that we now feel capable of distilling complex measures of performance into meaningful sound-bite information that is expected to be useful to owners, developers, tenants, lenders, and insurers in their building procurement transactions. A recent example of the mismatch in public expectations was the performance of a full range of old and modern buildings in the Central Business District (CBD) of Christchurch, New Zealand during the September 2010 and February 2011 earthquakes. The 2010 event was classified as a design level event, and the level of damage was such that the majority of the CBD was operational within weeks of the event. This was followed by February 2011 event that was classified as a maximum credible (MCE) event. Two buildings collapsed but the others performed as expected by the structural engineering profession in that they provided life safety for the occupants. What was not expected by the public at large was the need to demolish 70% of the buildings in the CBD. THE UNITED STATES RESILIENCY COUNCIL® The United States Resiliency Council® (USRC) was conceived based on ideas originating from the Structural Engineers Association of Northern California (SEAONC) as early as 2006, and input obtained from the FEMA-funded workshop on a rating system in 2011. The stated mission of the USRC is to become the administrative vehicle for implementing a building performance rating system. As such, it would promote and implement a rating system, educate the public about hazards associated with buildings, credential engineers and other professionals to perform ratings, and review ratings for conformance to the technical methodologies. Recently, the confluence of a series of events has led to an increase in urgency and an acceleration in USRC development activities. These include: (1) completion of the FEMA P-58 methodology quantifying performance in terms of repair cost, repair time, and casualties; (2) the development of the SEAONC Earthquake Performance Rating System (EPRS) which envisioned the first translation between existing engineering tools and a building rating system; and (3) the high-profile effort in the City of Los Angeles to identify and mitigate their seismic risk, as announced by the Mayor in November 2014. These events have resulted in the technology, vision, and demand needed to make the vision of a building rating system a reality. USERS OF THE RATING SYSTEM The rating system should be usable by all occupants, buyers, sellers, and tenants of a building. Thus, the audience for the system includes a broad and general population, many of whom know little about seismic risk. The most frequent users may be facility experts (structural engineers, brokers, insurance industry, investors), and the system should be usable by all who assess, quantify, reduce, mitigate, insure or accept risk. However, the system requires integrity and clarity without regard to the users or their desires. A potential list of users would include:  On-site—tenants, lessees, employees  Real estate—  Developers, brokers, property managers  Owners and potential owners (investors, corporations, governments, individuals)  Financial sector—lenders, insurers, re-insurers  Public sector—utilities, planners, local agencies, schools, religious institutions, federal agencies  Building professionals—engineers, architects, contractors POTENTIAL APPLICATIONS OF A RATING SYSTEM The greatest value of a system is one that meshes with economic decisions. Thus, there are a number of potential applications with an important one being a building rating that is disclosed as part of a real estate sales transaction. As the system achieves increasing acceptance, mortgage lenders could potentially use it in the way they currently use PMLs. In the context of a sales transaction, we envision that market pressures would encourage buyers and/or sellers to obtain a rating, making it part of pre-purchase due diligence. A related situation which could initiate a rating to be obtained is a lease turnover. Examples of this market mechanism include the BOMA rating system for office space (Class A, B, C), and building inspections of houses. In addition, both the Federal and State General Services Administration (GSA) may require a rating to be obtained as a means of prioritizing the buildings they lease, and the U.S. Green Building Council (GBC) could use it as part of sustainability criteria. A range of other potential uses includes:  New construction as part of permit process  Voluntarily by developers if market demand is perceived  Required as part of the permit process  Alternative to the current PML process  Required by lenders and insurance companies  Public buildings  Occupants’ right to know  Existing buildings in place of a retrofit mandate  Provides information for tenants and leasee’s to make more rational decisions; they may be happy to pay a lower rent for a higher risk building RATING SYSTEM DIMENSIONS AND DEFINITIONS The USRC rating system dimensions and definitions are based on ideas and concepts from the SEAONC Earthquake Performance Rating System (Stillwell et al., 2008; SEAONC 2009, 2011, 2012). These have since been vetted by the USRC Technical Advisory Committee and the USRC Stakeholders Advisory Committee. The current USRC system consists of three rating dimensions (safety, repair cost, and time to regain basic function):  The SAFETY rating dimension addresses thresholds for the building in terms of the potential for people in the building to get out after an earthquake event and avoid bodily injuries or loss of life.  The REPAIR COST rating dimension is an estimate of the cost to repair the building after the earthquake event. REPAIR COST is defined as a percentage of the building’s overall replacement cost prior to the earthquake.  The TIME TO REGAIN BASIC FUNCTION rating represents an estimate of the minimum timeframe to carry out sufficient repairs and to remove major safety hazards and obstacles to regain occupancy and use of the building, but not necessarily restore it to its full intended functions and operations as it existed prior to the earthquake. Within each dimension, definitions are keyed to five levels of performance. Levels of performance are communicated using star symbols, with more stars equating to higher (or better) performance. The current rating dimensions and performance level defini