Accounting for the slow pace buildings are brought up to current code in benefit-cost studies

Published

April 8, 2026

Author(s)

Kenneth Harrison, Tasnim Faiz, William Hughes, Jennifer Helgeson

Abstract

Benefit-cost analysis of building codes has revealed significant long-term benefits. Prior traditional BCA mainly contemplates the benefits of a building or set of buildings adhering to a new building code at a single point in time, e.g., in the current year. This work, in contrast, focuses on a broader spatial scale (e.g., community), recognizing that the benefits of code compliance across the community will occur over time, driven by the typically slow pace of replacement or improvement of existing buildings and of new construction. A new Community Benefit Discount Factor (CBDF) is introduced that can be used to adjust a traditional BCA to account for the timing of building code compliance for existing buildings. The CDBF addresses the economic discounting of the future costs and benefits of code compliance as they occur over time. The focus is on existing buildings undergoing replacement or substantial improvements that require compliance with current building codes for new construction. Building life (time to demolition), has previously been modeled stochastically with survival functions, the approach taken here to model the timing until replacement or substantial improvement. Assuming the common Weibull survival function, new formulas are developed for computing the CBDF. The formulas are developed for a single building, which can be extended to each building in the community. The application of the CBDF is demonstrated under differing discount rates. Finally, limitations and potential future directions of this research are discussed. The CBDF approach can be used to assess the benefit of adopting new building codes, or adding new local provisions to the model codes. Additionally, outputs of this process can be used as inputs to other assessment tools, such as the NIST Alternatives for Resilient Communities (ARC) Tool and the NIST Economic Decision Guide Software (EDGe$) Tool.

Citation

NIST Research Brief (RB) - 11

Report Number

11

Pub Type

NIST Pubs

Download Paper

https://doi.org/10.6028/NIST.RB.11

Local Download

Keywords

benefit-cost analysis, building stock turnover, survival functions, discounting, building codes

Citation

Harrison, K. , Faiz, T. , Hughes, W. and Helgeson, J. (2026), Accounting for the slow pace buildings are brought up to current code in benefit-cost studies, NIST Research Brief (RB), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.RB.11, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=960919 (Accessed April 9, 2026)