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Experts estimate that earthquake strengthening installations WILL FAIL to perform as expected in as many as 90% of retrofitted houses.

In December, 2011, the New York Times published an article estimating that one-third to two-thirds of non-engineered earthquake retrofits in the San Francisco Bay Area are installed incorrectly. (See the article here:  http://www.nytimes.com/2011/12/23/us/seismic-retrofits-offer-shaky-assurance-in-california.html?pagewanted=all&_r=0)  In 2006, the Contra Costa Times estimated that 69% of retrofits would not function as expected. The Golden Gate Chapter of the American […]

Common Misconception: My Building Survived 1989 Earthquake So I Don’t Need A Retrofit

Building owners commonly believe good performance of their building during the 1989 Loma Prieta earthquake validates a building as being safe to withstand a major earthquake. However, the Loma Prieta earthquake registered a magnitude 6.9 with an epicenter located approximately 60 miles from San Francisco. For comparison, the Great Earthquake of 1906 registered a magnitude of […]

New Method of evaluating and strengthening of Soft Story Buildings

A small investment in engineering will potentially save on overall project construction costs.

El Cerrito Now Requires Mandatory Retrofit

Inside the Bay Area reported that El Cerrito has adopted a mandatory retrofit ordinance twenty years after the Loma Prieta earthquake. This program had supporters including an earthquake geologist who expressed that URM’s are a definitive factor on who survives in the event of an earthquake. He also stated that in April a moderate earthquake […]

San Francisco Soft Story Screening Forms Are Being Mailed This Week

A licensed architect or civil or structural engineer would need to visit the building and complete your screening form as it requires a better understanding of ordinance, scope, code language, and construction type, than is typically possessed by a building owner or a contractor.
Enginious Structures, Inc. can assist you in the screening of your building and completing the form for you. This will clarify whether or not you are exempt from any further action. The form requires a design professional to answer the following questions.
• Is the building wood-frame construction?
• Was the building permitted prior to January 1, 1978?
• Is the building three or more stories, or two stories over a basement or under floor area that extends above the grade? (Please, keep in mind that the definition of “stories” that the Department of Building Inspection utilizes may not be what you are familiar with.)
• Does the building contain five or more dwelling units?
If we find that the answer is yes to any of the department questions but you still believe your building is exempt you can file the optional evaluation form as discussed above. We can assist you in this process as well.
Our fee for the site visit and filling out the screening form is $250- $500 depending on the building size. However, if the building needs further evaluation and you hire us to do this evaluation and design a retrofit if necessary we will deduct the evaluation cost from our design fee; so the cost of the screening is essentially zero.

New Research on Soft-Story Retrofitting

A team of researches at Colorado State University have found that earthquake retrofitting significantly lessens the probability of a soft-story building’s collapse.  While the stronger earthquakes that were tested caused some damage to the model buildings, the structures remained safe for occupancy, unlike the models that had not been strengthened prior to testing. To read […]

SF’s Mandatory Seismic Retrofit Program for Soft-Story Buildings

Below is a summary of what you need to know about the new ordinance in plain words. IS MY BUILDING A SOFT-STORY BUILDING? If the following four requirements apply to your building, then it is a suspect for a soft story building. 1) Wood-frame building with either 3+ stories, OR 2 stories over a basement/underfloor […]

D/B or not D/B, that is the question

The term “soft story” building describes a building with a level or story that is significantly more flexible than stories above it, such as an open parking area or a commercial space, which can be hazardous in the event of an earthquake.  The Bay Area has thousands of these building.  Damage to soft story buildings […]

What did we learn from the SF voluntary soft story ordinance – Voluntary programs don’t work!

Voluntary programs don’t work!

San Francisco Soft-Story Ordinance

On March 16, 2010, the San Francisco Board of Supervisors passed a voluntary soft-story retrofit program, which will take effect on April 19, 2010. This program benefits soft-story building owners who voluntary retrofit their buildings by: Waiving building department plan review fees, which can amount to hundreds or even thousands of dollars per project. Expediting […]