by Haris Quintana
Does your multi-level building have a ground level parking or a large open space on the ground floor, typically used for gatherings and other functions that require an open area? Was your building every reinforced as a safety precaution against earthquakes? Do you know what the concept of soft story retrofitting? If you end up clueless and searching for answers after these questions, you might want to stick around and read through, because this could greatly affect your property and your business.
If you don’t have any idea what a soft story retrofit is, don’t worry, you’re not alone. But if you live in Los Angeles, Santa Monica, and other earthquake prone areas, then you quickly need to learn about the concept because it could save you from a lot of headaches in the future. Simply put, soft story retrofitting is typically required by law for buildings in areas often frequented by earthquakes. You might have had your building constructed sometime after World War II during a property boom, or you might have recently acquired it without knowing about the guidelines. Thankfully, it’s not too late for you.
You can have your soft story building retrofitted so that it can comply with the building codes of the area. You don’t need to tear down and demolish your property, because a good contractor can just reinforce the whole building with modern construction materials in record time.
But before all that, let’s have a refresher on this concept. This way, you’ll fully understand the need for retrofitting to your building.
Soft story building definition
A soft story building is a structure with multiple floors built over a ground level that has large openings, like a parking area or above-ground storage, and more. These are considered to be the weakest part of your building, and will be the first to give when a strong-enough earthquake hits. To cut it short, soft story buildings are weak and will collapse due to prolonged shaking. These buildings include those built prior to 1979, when the engineering standards are comparably weaker than the modern ones we have today.
Soft story buildings are weak because of the unreinforced openings they have on the ground floor, causing more movement that the structure can withstand. With no strong earthquakes prior, the old building codes didn’t really consider the occurrence of an earthquake strong enough to topple buildings during those times. What usually happens is that the ground level caves in, and top floors collapse on top of the lower level, causing massive damage to your property, and even loss of life.
Earthquake-proofing an old building
If you don’t know whether you need to retrofit your building or not, you can consider the following information and see if anything applies to your property.
Your building was built using the building code standard before 1978 – as mentioned earlier, people back then were blissfully unaware of strong earthquakes. It could either be from the lack of recorded data, or simply overlooked the fact that some cities sit directly above fault lines. The building codes back then were very lenient, so it’s almost impossible to have a building that’s still up today that hasn’t been renovated and reinforced to comply with modern requirements.
Contains ground floor parking or a large, open space for different functions in the building – any building owner would attest to the importance of having a parking area in their building. It attracts more businesses and makes it more convenient to tenants with vehicles. And since it’s just a parking space, there’s no need to pay much attention to it, even if the rest of the building is sitting on top of it. With enough load-bearing beams and sturdy columns, you think you’ve done enough to support the weight of your building.
Has 2 or more stories with wood-frame construction – back in the 70s, there a shortage in metal building materials was augmented by using actual wood for the construction. It’s not that wood isn’t strong, it’s just that having more than 2 stories sitting on top of a wooden frame is really risky. Overtime, would could fail. It could rot, be eaten by termites, by damaged by water, and more. Old buildings that still has wood frame construction and are yet to be demolished are ticking time bombs—accidents waiting to happen.
Soft Story Retrofitting
During the process of retrofitting your building, the weakest parts would be structurally reinforced so that it can resist or counteract the seismic movement when an earthquake happens. What the construction company does is to install structural steel connectors and I-beams on your building to boost the resistance to the seismic movement. Special frames can be retrofitted on the weak parts, and they could either be welded or bolted and prefabricated for ease of installation.
The retrofitting process starts with creating a site plan for the building that needs reinforcement. This site plan is not only for the building, but also for the other buildings on the property. A licensed structural engineer will use these plans to create a solution to the structural weaknesses of the building in question.
Once that’s done, these plans will be brought forward to the city planners and city engineering. They will check if everything is up to code. You can also ask for prior guidance to know what you should do and add in order to get city approval.
Once approved, get a quote of the cost of construction, give notice to tenants, if there are any, about the construction that’s about to happen. It because the retrofitting process would often affect the plumbing and electrical infrastructure of the building, so the tenants will experience significant service disruption.
Wrapping up
Once you get the ball rolling on the construction, it will only be a matter of time before your old, soft story building will be up to code, reinforced, and prepared for earthquakes. Getting your building up to code could be a tedious process, but it is a necessary step if you want to ensure safety for your tenants, and compliance to the laws and regulations of your area.