Most seismic reinforcements of soft-story apartment buildings in Los Angeles require steel moment frames. The cost for each frame is between $24K to $29K. However, When possible, it is economically beneficial to reinforce the existing shear walls of a soft story building by adding plywood to the walls, instead of new steel frames.
Some engineers argue that the flexibility of a shear wall will actually outperform steel frames because the joints of steel frames are too rigid and will fail.
Whenever possible, an engineer will use a shear wall instead of steel moment frames-saving you money without compromising safety.
Seismic Retrofit Design Economics: Value Engineering for Soft Story Building.
Experience is essential when designing engineering plans for seismic retrofitting projects. A city-approved set of plans usually cost between $5,500 for a small building to $8,000 for a large size building, but not all engineering design are equal. Even after it gets approved, a $5,500 building plan could end up costing you more on the construction end.
What do I mean? The concept is called “value engineering.”
The challenge for engineers in the development of seismic retrofit plans is to analyze the complexities of each building and decide on the best way to position the steel, or whether a shear wall is a better, feasible solution to produce results that the city will approve of and issue a permit for.
Experience is key; an experienced engineer understands the importance of coming up with plans that take all of the elements into account, provides value engineering that gets approved and calls for design characteristics that save building owners money.
What Should Your Seismic Engineer Know?
The engineer should be aware of when to use shear walls instead of steel frames, what size steel to use, and the appropriate steel frame location, based on existing conditions. The engineer should also avoid compromising parking and ensure the least interference to everyday life. Knowing where and how to place steel frames around the parking garage opening or how to use the existing walls is essential to a proper seismic retrofit design.
So, when it’s time to start your retrofitting projects, make sure you pick someone with a lot of experience.
Ask specifically about how they plan to utilize “value engineering”, and if you are not entirely satisfied with their answers, feel free to contact us and let us know how we can be of assistance.
We will inspect your building, provide you with a free building analysis, reasonable construction cost and mitigate the seismic retrofit issues of your building all the way to full compliance.