Objective - To develop a cost-estimating relationship between building profiles (construction type, size, age, location), which represent buildings that are federally owned, leased, financed, or regulated (‘federal buildings’), and risk mitigation activities implemented to improve seismic performance. Performance is defined here as the ability of buildings to reduce risks to occupants and to continue to provide essential functions following seismic events. Mitigation of structural and non-structural risks are considered. A prioritization strategy, consistent with economic best practices, is developed to aid decision-making related to the staging of mitigation activities within or across buildings.
What is the Technical Idea? Advancements in measurement science are needed to develop a cost-estimating relationship between federal building profiles and earthquake risk mitigation activities, to better inform investment and code decisions. Executive Order 13717 Establishing a Federal Earthquake Risk Management Standard states, “When making investment decisions related to Federal buildings, each executive department and agency (agency) responsible for implementing this order shall seek to enhance resilience by reducing risk to the lives of building occupants and improving continued performance of essential functions following future earthquakes.” Using historical data, estimates of the ratio of building mitigation (including retrofit) costs to replacement value are generated, based on the analysis of: (1) case studies, which provide detailed accounting of the types of seismic upgrades performed, along with context for the improvements, and (2) statistical analysis of federal building inventory data, which relates seismic-related building improvement costs over a distribution of buildings types, relative code improvement, and hazard zones.
The analyses will provide insights into actual investment decisions and their costs, including any staging criteria used to phase mitigation activities over time, avoiding large upfront costs. It will allow a linkage to be made between costs spent and remedied seismic risk, conditioned on building size and prior risk state (e.g., building code at time of original construction).
What is the Research Plan? The research plan is comprised of three major activities: (1) case study analysis, (2) statistical analysis of federal building inventory data, and (3) development of a staging protocol based on economic best practices. Activities 1 and 2 can be completed concurrently, although the findings from the case studies will inform data requirements for the statistical analysis.
The case studies will provide detailed analysis of the major cost drivers related to seismic mitigation in federal buildings, along with the nature of the work performed. They will be based on a limited number of individual building retrofit projects. The focus will include GSA and VA (or other) building data and reports documenting seismic upgrades, including costs and extent of upgrade, and provide detailed information on specific engineering solutions and associated costs. This research activity will be completed primarily through a contract with an engineering/cost-estimation firm. In addition, the output will inform the statistical effort, by defining minimum data requirements and identifying key cost variables and likely sources of cost variability.
The statistical analysis will provide a general analysis on a large number of building retrofit projects, including information on the distribution of the types of buildings and associate retrofit costs. The results will be used to intersect, spatially, with seismic hazard maps in GIS to produce cost/building profiles by hazard zones. The analysis will be based on data obtained from GSA, DoD, and/or VA describing building records for costs of seismic improvements. Depending on extent of coverage, the federal data may be supplemented with privately-collected building permits (or similar) data. The analysis will quantify correlations between mitigation costs and building location (seismic risk), age and construction type (relative to extent of code improvement), size (square footage; number of floors), and ownership. Additional correlations will be measured depending on the extent of data obtained.
Linkages between the case study and statistical analyses will be created to project the detailed cost-estimating relationship from the case studies onto the distribution of building profiles developed through the statistical analysis. This will provide insights into potential future costs of seismic mitigation of federal buildings. The results are meant to be generalizable to ‘building profiles’ (categories of buildings) rather than specific to particular buildings. It will answer questions related to the size of the investment needed to remediate federal buildings, based on historical transactions. It is not meant to identify risks of individual buildings, nor estimate individual building retrofit costs.
A prioritization strategy will be developed to facilitate the decision of staging mitigation activities within or across buildings. These will be consistent with ASTM E06.81 standards on building economics.