Seismic Retrofitting
Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motions or soil failure due to earthquakes. With better understanding of seismic demand on structures the need for seismic retrofitting is well acknowledged. Prior to the introduction of modern seismic codes in the late 1960s many structures were designed without adequate detailing and reinforcement for seismic protection. The goal of a retrofit is to secure/bolt down a structure to the concrete foundation. During a seismic event these reinforcements minimize the damage to a structure.
Diviney Construction specializes in a wide range of seismic retrofitting services including, house bolting, foundation bolting, cripple wall bracing, soft story retrofitting, shear walls, sister foundations, foundation underpinning, floor leveling and foundation repair
Seismic retrofitting involves installing engineered metal connectors and other reinforcing materials at key stress points throughout the structure. This specially designed hardware includes strap ties, anchor bolts, hold downs, anchors and anchor bolts and framing angles. Sometimes, wood blocking and structural sheathing is included in retrofit projects.
Seismic retrofitting is more than a good idea –
in some cases, it is the law.
(Source: San Francisco Department of Building Inspection)
The Mandatory Soft Story Retrofit Program (MSSP) was created in 2013 as a multi-year community-based effort led by the Earthquake Safety Implementation Program and enforced by the Department of Building Inspection to ensure the safety and resilience of San Francisco’s housing stock through the retrofit of older, wood-framed, multi-family buildings with a soft-story condition.
As part of this program, all affected property owners were noticed beginning in September 2013 and were required to have submitted their screening forms to DBI by September 15, 2014. DBI has achieved over a 99% response to the program.
We encourage property owners of soft story buildings to take the necessary steps to comply with program requirements by filing for a permit to ensure their properties are seismically safe in anticipation of the next big quake.
The ordinance applies to wood-frame buildings of three or more stories or two stories over a basement or underfloor area that have any portion extending above grade and containing five or more residential dwelling units where the permit to construct was applied for prior to January 1, 1978, and where the building has not yet been seismically strengthened.
While these types of buildings and their associated risks are found in every neighborhood in San Francisco, they are most commonly found in the following districts: Mission, Western Addition, Richmond, North Beach, Marina District.
We cannot predict when the next earthquake will strike, but we can work together to protect ourselves and our properties.