Portland’s URM Seismic Retrofit Project
Walt McMonies authored an article in the Spring 2016 edition of Multifamily NW’s Apartment Report titled “Portland’s URM Seismic Retrofit Project.” In the article, McMonies discussed the potential impacts of a significant earthquake on unreinforced masonry (URM) buildings and proposed City Code changes to expedite the seismic retrofitting of URM buildings. He also discussed what regulatory changes are needed and what financial support might be available for URM owners.
In a large earthquake, URM buildings are vulnerable to a high level of damage or collapse. The City’s approximate 1,800 URM buildings include some of the City’s most historically significant structures, and provide cultural character, moderate housing for 8,000 to 10,000 people and incubator office and creative commercial space for thousands more.Although it is technically feasible to seismically upgrade an URM, the financial feasibility of those upgrades is a real question. The typical URM building owner analyzes a major expenditure on a “money invested, money repaid” (payback) basis. Looking at seismic upgrading on a payback basis, URM life/safety upgrades in Portland are currently at best marginally cost effective, given that upgrading takes 20 to 25 years to payback the owner’s investment through higher rents and lower expenses (in particular, less costly earthquake insurance and a lower cost of mortgage funds).