Unreinforced Masonry Building Law Update:

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Release date: 
November 4, 1999
Release Number: 
R9-99-20

The California Seismic Safety Commission is asking local governments in the state's highest seismic hazard regions to provide an update on the status of their compliance with the state's Unreinforced Masonry Building (URM) Law.

The URM Law was enacted in 1986 and required local governments in Seismic Zone 4 to do three things:

1) Create an inventory of unreinforced masonry buildings in their jurisdictions;

2) Establish an earthquake loss reduction program for these buildings; and

3) Report all information about these efforts to the Seismic Safety Commission. (8875 Government Code)

Unreinforced masonry buildings are vulnerable to collapse and life loss in damaging earthquakes. Tops of walls can separate and fall, walls can pull apart from floors and roofs, and parts of walls can become unstable in strong ground shaking.

53 percent of the affected jurisdictions now require seismic retrofits of these buildings. Over 78 percent of the inventoried URM buildings are in mandatory strengthening programs. Retrofitting involves bracing tops of walls, improving connections between walls, floors, and roofs, and ensuring that wall mortar has minimal strength. Retrofitting can significantly reduce the risk to life.

The Commission is particularly interested in knowing how much retrofit progress has been made since the last survey in the summer of 1997. At that time, more than half of the 25,480 URM buildings had been retrofitted.

Progress from the 288 effected cities and counties in Seismic Zone 4 that the Commission receives by January 31, 2001 will be compiled and sent to the state Legislature for their information.

The Commission is also encouraging local governments to collect and share their databases of vulnerable buildings for joint use with the Governor's Office of Emergency Services and the Federal Emergency Management Agency (FEMA). FEMA recently developed uniform earthquake loss estimation software called HAZUS that is available to governments at low cost. Governments can now use HAZUS to compile information about specific buildings vulnerable to earthquake damage for pre-earthquake planning and post-earthquake emergency response and recovery.

In the 1997 URM survey, progress for over 85 percent of all the inventoried URM buildings were reported by local governments. The Commission is very grateful for the hard work and commitment of building departments to manage this program and reduce losses from URM buildings. Owners of retrofitted buildings are also commended for cooperating and financing the work to help save lives.

If you would like more information about this effort, please contact Mr. Fred Turner at the Seismic Safety Commission at fturner@quiknet.com or 916-263-0582.

Last Updated: 
July 19, 2012 - 23:02
State/Tribal Government or Region: 
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