http://www.softstoryretrofitpros.com/blog/rss/feedsLicensed General Contractor in Southern California. We design and build soft-story retrofit construction projects in Southern California including Los Angeles, Santa Monica, Beverly Hills, and West Hollywood on time and at a fair price.Wed, 29 Apr 2026 03:15:38 -0700http://www.softstoryretrofitpros.com/blog/post/did-you-feel-it-37-quake-shakes-los-angeles--how-to-protect-your-homehttp://www.softstoryretrofitpros.com/blog/post/did-you-feel-it-37-quake-shakes-los-angeles--how-to-protect-your-home Did you feel the recent magnitude 3.7 earthquake this week? It was near the Newport-Inglewood Fault Zone A magnitude 3.7 earthquake rattled Windsor-Hills, a neighborhood neighboring South Los Angeles & Culver City, just a few minutes after midnight. Several Angelenos and even some of our Bay Cities Construction employees were woken up the the light shaking, enough to rattle dishes and plenty of nerves. The recent earthquake struck near the Newport-Inglewood Fault Zone (NIFZ), a 47 mile long strike-slip fault that extends from Culver City in the north, all the way down to Newport Beach, in Orange County. The San Andreas Fault, capable of producing 'The Big One', is just one of several faults that threaten the South Bay and Greater Los Angeles area. So what can you do to prepare for an earthquake? Plently - This article will help you learn more about the Newport-Inglewood Fault Zone (NIFZ), how you can protect your home from earthquakes, and how you can prepare for natural disasters. The Newport-Inglewood Fault Zone Newport-Inglewood Fault Zone on a Map The Newport-Inglewood Fault Zone (NIFZ) has long been considered one of Southern California's most potentially devastating seismic zones, it produced Southern California's deadliest earthquake to date. Back in 1933, a magnitude 6.4 earthquake struck Long Beach and killed 120 people. Most fatalities resulted from people running out of buildings and exposing themselves to falling debris, many of them in were schools built from unreinforced masonry (URM). School buildings were among the most heavily damaged structures, the devastating damage caused several changes to building codes shortly after. Image courtesy of UCSB/Jim Boles Some of the most densely populated cities in Southern California are located near the NIFZ, including Culver City, Inglewood, South Los Angeles, Hawthorne, Compton, Signal Hill, Long Beach, Huntington Beach, and Newport Beach. All of which could experience an earthquake with a magnitude 6.0 or higher. How to Prepare for an Earthquake What is a Seismic Retrofit (Brace+Bolt) Seismic Retrofit of a Raised Foundation As a Southern California resident, it is important to plan & prepare for a large earthquake. If your home was built before the 1980's and it has a raised foundation - you should retrofit the foundation as soon as possible. A seismic retrofit can help protect your home from expensive foundation damage caused by an earthquake. So what is a seismic retrofit? A seismic retrofit is a reinforcement to the foundation-and-framing connection, it is achieved by installing heavy steel plates, and anchor screws, new framing elements to create a stronger connection to the foundation. We have an in-depth article that you can read HERE if you'd like to learn more about seismic retrofits. Seismic Gas Shut-Off Valve These small steps can help prevent fire-damage Did you know that the majority of property damage after an earthquake is caused by fire? A strong earthquake can rupture your water line and natural-gas line, which can cause a fire to spread throughout the property very quickly. A Seismic Gas Shut-Off Valve can help prevent gas fires before they start - this little device is designed to automatically shut off the gas line whenever large seismic movement is detected, all by itself. This device is affordable, easy to install, and can help you prevent thousands' worth of property damage. Strapping down your water heater is also a good idea - in an earthquake they can topple over and can cause fires. So it's also a good idea to keep several fire extinguishers around the house. Emergency Preparedness Having two weeks worth of food is a smart idea. We live in earthquake country - that's a fact we can't escape. In the event of a large earthquake, water & power service can be interrupted for weeks. And if COVID-19 has taught us anything it's that grocery stores can quickly be emptied out, so having food stock at home to last up to 3 weeks is a smart idea. Want to Learn More? If you want to learn more about seismic retrofits for residential homes - we recommend the articles below: Average Price of a Foundation Boltdown - Why do Prices Vary So Much? What is a Brace+Bolt Retrofit? How to Protect Your Home from Earthquakes Everything You Need to Know About Seismic Retrofits for Homes Written by Alexander Rodriguez. MBA, GC. ***This Blog Article Was Originally Published on the Bay Cities Construction website on Wednesday, April 22, 2020*** Tue, 28 Apr 2020 16:58:00 -0700http://www.softstoryretrofitpros.com/blog/post/what-is-a-bracebolt-retrofit-how-to-protect-your-home-from-earthquakeshttp://www.softstoryretrofitpros.com/blog/post/what-is-a-bracebolt-retrofit-how-to-protect-your-home-from-earthquakes Protecting Your Home from Earthquakes is Easier than Ever. We all know that California is ‘Earthquake Country’, but did you know that nearly every neighborhood in Los Angeles is near an earthquake fault? In fact according to the Southern California Earthquake Center (Plesch, 2007) there are over 140 active faults in Southern California. Nervous? Don’t be, you can protect your home with a Seismic Retrofit. If your home has a raised foundation and was built before the 1970s, a Brace + Bolt Seismic Retrofit might be right for you. Our short article will help explain what a Seismic Retrofit is, how long the installation will take, and why retrofitting your foundation is a smart idea. Our video helps explain what a 'Brace & Bolt Retrofit' is. What Does 'Brace & Bolt' Mean? An earthquake bolt down is a seismic retrofit that helps reinforce the connection between your home’s foundation and the home’s frame. This type of seismic retrofit is an economical way of preventing your house from ‘sliding off’ its foundation. The ‘Brace & Bolt’ namesake comes from the bracing of the frame/subfloor and then bolting to the foundation that will be required as part of the seismic retrofit. URFP Plates Installed at Our Recent Brace+Bolt Retrofit Projects. Let’s examine the wood-frame of the typical home in Los Angeles, and remember that the goal of a Brace & Bolt Retrofit is to reinforce the connection between the framing and the foundation. Every wood-framed house has four (4) main framing systems, including the below. Roof System – Roof framing, roof rafters, and ceiling joists Wall System – Wall studs of 2x6 or 2x4 dimension lumber. Floor System – Floor Boards of 2x8 or 2x12 dimension lumber, held up by 4x8 girders. The top of the floor joists usually consists of either plywood or diagonal 1x6 boards. Foundation System- Concrete stem walls with footings, with piers holding up the floor system. In the image below, you can see a cross-section in which all these components are visible. Anatomy of a Floor Framing System During an earthquake, your home can experience lateral shear forces that will cause it to sway in a side-to-side motion. The connection points in the home’s frame will take the brunt of these forces, something that they were never designed to do, they are not intended to resist lateral force. If the lateral shear loads are big enough, the floor system could separate from the foundation as a result, causing the house to ‘slip off’ the foundation. This type of earthquake damage is extremely expensive to repair and yet relatively affordable to prevent. In the picture below you can see how this home’s foundation was damaged after the recent Ridgecrest Earthquakes. The Retrofit Pros team visited both Ridgecrest, CA and Trona, CA to observe damaged structures and to learn how to prevent earthquake damage in homes. Our team observed several homes with foundation damage, it was the most common type of structural damage we encountered in Trona, CA. Mobile-home with foundation damage caused by Ridgecrest Earthquakes. Common Foundation Retrofit Techniques Retrofit contractors have traditionally relied on metal hardware components from Simpson Strong-Tie and Mitek USP to retrofit homes with raised-foundations. These metal connectors make retrofitting a wood frame structure much easier. These foundation plates ensure a solid connection between the concrete foundation and the wood-frame of the home. Below are some examples of the different foundation plate hardware used when bolting down a foundation. The most popular foundation plates are made by Simpson Strong-Tie & MiTek USP These steel connectors are truly technical marvels, however, it is important to note residential homes are of wood-frame construction and are only as strong as the current condition of the lumber. This means that if your home’s frame has termite damage or rotting wood, your foundation is in need of repair, you don’t just want to rely on the steel plate connections. Connecting steel brackets and plates to damaged lumber will diminish the effectiveness of a brace & bolt foundation retrofit. A true construction expert will give careful consideration to the condition of the existing wood members in the floor system. Foundation Retrofit Components As a general contractor specializing in seismic retrofits for residential homes, we use four main components to create a better connection between the foundation and the frame. A Brace & Bolt Foundation Retrofit uses four main components. Our team prefers the Simpson Strong-Tie line of products and so we’ll show you just some of the products we use when we retrofit foundations. Common components used to bolt-down a foundation. Retrofit Hardware Used by Retrofit Pros: 1 - Simpson Foundation Plates (URFP/FRFP) 2 - Simpson A35 Framing Angles 3 - Heavy Angle Transfer Angle (HSLQ) 4 - TITEN HD Concrete Anchor Wood-Frame Strengthening Techniques Our local Simpson Strong-Tie rep Carlos Z. visited our job site. During our larger soft-story retrofit projects our team found a need to create a framing technique to strengthen the existing wood frame, we dubbed it the ‘Rodriguez Wood-Frame Transfer Technique'. No other company uses this type of framing technique to bolt down a house. We use this framing technique to strengthen a building's wood frame and to create a predictable load path transfer of seismic forces. This technique is so strong and dependable, it allows the transfer of 27,000 lbf pounds of force along the load path. Because it is a proprietary construction method, we can only share how this framing technique works during our in-person meeting. ============================================================= Want to Learn More? What Can You Do to Protect Your Home from Earthquakes? What is a Soft-Story Seismic Retrofit? References: Plesch, A.; et al. (December 2007), "Community Fault Model (CFM) for Southern California" (PDF), Bulletin of the Seismological Society of America, 97 (6): 1793–1802, Mon, 25 Nov 2019 17:09:00 -0700http://www.softstoryretrofitpros.com/blog/post/pro-vs-amateur--selecting-a-softstory-contractor--how-to-avoid-getting-scammedhttp://www.softstoryretrofitpros.com/blog/post/pro-vs-amateur--selecting-a-softstory-contractor--how-to-avoid-getting-scammed Lots of people are doing retrofits - avoid scammers, snake oil salesmen, and grifters. When the Los Angeles City Council adopted the “Mandatory Seismic Retrofit” ordinance 183893 in 2016 it created a boom in construction worth upwards of $1.2 Billion dollars. This has triggered a manic gold rush frenzy in freshly minted would-be contractors that did not exist a few years ago. You can tell they are newcomers because their Contractors License No. starts at 100XXX. I have witnessed many cases where contractors pose as a “retrofit expert” but have had a CSLB license for less 6 months, and I’ve seen other cases where the wannabe “expert” doesn’t even have a license. What kind of ‘soft-story retrofit expert’ doesn’t have a contractor's license? Or any real construction experience doing seismic retrofits. I want to help you avoid these bad contractors that will try to sell you something that won’t work. More often than not these “experts” submit incredibly low bids, far lower than anyone else because they don’t know what they are doing. They do not realize how complex a seismic retrofit project really is. Or you’ll see them as “third parties” (as a broker, property manager, or even a construction consultant) that try to wedge themselves in the transaction to get a commission. Why though? I have no problem with people trying to earn some money, but at least contribute something of value in the exchange or else get the heck out of the way. Ask the Right Questions I want to help you avoid these people, people who want to leach off of your hard work. So here are some questions you can ask to determine if you are dealing with a scammer or with someone who is truly an expert. These are three questions you should ask every contractor you are considering for your soft-story retrofit project in Los Angeles, Santa Monica, West Hollywood, Beverly Hills or Pasadena. “Tell me about you approach to retrofitting a soft-story building? What is the best way to do the retrofit?” An amateur contractor will say: “We put a cantilevered Column, put it in and all done” They will offer very little detail, mostly because they don’t know what to do. They just now cantilevered columns are cheaper. A pro contractor will say: “We open up the stucco asses the condition of the building framing and determine how much wood we need to add to the building to prepare it for the steel. The new steel is spread out over a wide footprint to provide a reliable load path and increase building performance” A true pro will now that in most cases moment frames are the best solution, they also know about the importance of creating load paths to absorb lateral forces experienced during earthquakes. “What is the cheapest way to retrofit my building?” An amateur contractor will say: “A Cantilever Column is the cheapest option, and its easy to install, we add a few clips and that’s it.” A pro contractor will say: “Making the building perform is the cheapest thing to do, you want to protect this building. Every dollar you invest can prevent 12X in damage. It’ll cost more in the present, but the repair you’ll need to do after an earthquake will be significantly cheaper” “Can you give me a guaranteed construction price or firm bid before we get the plans done?” An amateur contractor will say: “Of course, my prices are firm” If they say yes, it’s a scammer. No one with any construction acumen will agree to this. Only inexperienced, desperate people will agree to such a daft request. No two buildings are truly alike. Termite damage and shallow footings need to be repaired in order for the retrofit to work correctly and the building to perform. A pro contractor will say: “Our guarantee is that we will use all of our experience, talent, and to protect your building. We want to achieve the most performance out of your building at a fair price. The building’s need will determine the price. Let’s inspect the wood-frame and footings to make the best decisions about how to retrofit the building. Once we have a gameplan we can determine how much it will cost.” Anything short of that and people are guessing on price, they’re lying. You don’t know how often work is delayed due to Field Change Orders (FCO) because the plans need to be revised. A pro should be able to give you detailed feedback about how to do the work and why that construction method is best. You should follow your instinct and make sure they are a good fit for you. Shallow answers with little details shows a person with a limited knowledge base. Sure, you can ask how many seismic retrofit projects they have under their belt, but a simple lie would be hard to detect. Want to Learn More? The Ugly Truth About Seismic Retrofits in Los Angeles Unintended Consequences of Using Cantilevered Columns Finding a Trustworthy Contractor for Your Seismic Retrofit Project Alexander Rodriguez is a Construction Industry Veteran with expertise in Seismic Retrofits for Wood-Frame Buildings. Fri, 01 Nov 2019 14:10:00 -0700http://www.softstoryretrofitpros.com/blog/post/seismic-retrofits-for-softstory-buildings--what-ive-learned-after-three-yearshttp://www.softstoryretrofitpros.com/blog/post/seismic-retrofits-for-softstory-buildings--what-ive-learned-after-three-years It's been three years since we started retrofitting soft-story buildings, here's what we've learned so far. A few years ago the city of Los Angeles passed Ordinance 183893 & 184081 to require seismic retrofits for Wood-Frame Apartment Buildings with 'Soft Story' (Soft, Weak, Open-Front) features. A short time after that my company began to work on 'Soft Story' seismic retrofit projects after my Structural Engineer approached me with a retrofit project. After years of working together, my engineer remarked: "I know your work... you should look into this soft-story retrofitting ordinance in LA". "I know your work... you should look into this soft-story retrofitting ordinance in LA" Since then I approached several colleagues from the Structural Engineers Association of Southern California (SEAOSC) to fully immerse myself in the field of seismic retrofits and seismic engineering. The ordinance presented a unique opportunity for contractors like myself to help protect structures and tenants from earthquakes, and since then I made it my mission to help make Los Angeles, Santa Monica, West Hollywood, Beverly Hills, and Pasadena more resilient. For those of you who don’t know me, I have been in construction for over 15 years and started this company during the Great Recession, and I am committed to helping make Southern California a safer place for everyone. In the three years of doing seismic retrofits, my team has worked on properties both big & small. We have also built retrofit solutions using the three main retrofit methodologies, including Moment Frames SMF/OMF (Special Moment Frames & Ordinary Moment Frames), Cantilevered Columns SCCS/OCCS (Special Cantilevered Column System & Ordinary Cantilevered Column System), and Shear Walls SW (Steel Shear Panels & Wood Shear Wall). In using all of these methods I have come to the realization that each one of them is best suited for a specific type of field condition. In determining what solution is best for a soft-story building I ask myself "What is the BEST solution for the building", because I want to make sure that the solution we use is the one that provides the most protection. "I want to make sure that the solution we use is the one that provides the most protection" Cantilevered Columns Don't Perform as Well as Special Moment Frames. Over the years I've gotten in touch with hundreds of property owners who want my team to submit a bid based on plans they've gotten design by another firm. The overwhelming majority of plans we've received to "bid" on, use a Cantilevered Column solution. In my experience over 100 sets of plans that have been sent to me use a type of Cantilevered Column solution, this retrofit method has become prolific. It's my professional opinion that in 85% of these plans using a cantilevered column is not a WISE choice, and it's not necessarily because cantilevered columns aren't strong enough (...trust me, STEEL IS STRONG). It's simply because a better solution could have been used but was ignored simply based on price while it's superior performance was ignored. Getting Technical Let me elaborate, and bear with me because it's going to get a bit technical, the cantilevered column solutions I've seen often replace existing Steel Pipe Columns SPC that carry gravity loads with a cantilevered column to handle both gravity loads and shear loads...and that's when bad things can happen. A large earthquake (Magnitude 7+ on the Richter Scale) will damage the base of the cantilever column. The top of the column can damage the gravity load beam that it is attached too, possibly causing unnecessary damage. In most cases, this type of damage is 100% preventable by simply leaving the Pipe Columns SPC in place and instead using a more comprehensive solution like a Special Moment Frame to reinforce the structure. Utilizing a cantilevered column retrofit can cause tens of thousands of dollars of damage that was avoidable. A damage caused by using the wrong design in the wrong location, simply because it's cheaper to install. The Simpson Yield Link structural fuse shown above in orange. Choose Better Performance Cost and money are important factors in choosing a solution for a soft story retrofit solution in Los Angeles. There is no doubt that seismic retrofit solutions for Soft-Story buildings that use Special Moment Frames are more expensive, slightly more expensive (the difference is a few thousand dollars). But a Special Moment Frame system will isolate shear forces into a specially designed Yield Link Structural Fuse. The Yield Link will absorb the damage in a replaceable section of the moment frame, a feature that is not offered using cantilevered column systems. Why does this matter? In the event of a large earthquake a cantilevered column that yields will need to be replaced entirely, and If the gravity beams that the cantilever is attached too is damaged it will also need to be replaced. By contrast, if a Special Moment Frame is damaged during an earthquake, only the damaged Yield Link section needs to be replaced, and not the entire system. Simpson Special Moment frame with Yield Link shown above in orange. Since the retrofit ordinance of Los Angeles was passed in 2016 over 50 new retrofit companies have appeared (trust me, I counted) that did not exist just a few years ago with brand new CSLB contractor licenses. I don’t like all the slimy people that have entered the soft-story business. General Contractors already have a bad rap, and I fear that these new wannabes will just be adding to the mix. If you have a new CSLB license that is less than 1-year old that doesn't make you an expert...simply said. I do not suffer fools gladly, but earthquakes don’t suffer amateurs well. Personally I would like to see a focus on delivering exceptional performance, craftsmanship, and pride in making amazingness happen. This retrofit work is meaningful and I want to work for people who value what we do and how we do it! Alexander Rodriguez, MBA, owner & founder of Bay Cities Construction & Soft Story Retrofit Pros is an Industry Expert in Residential Construction. Mon, 28 Oct 2019 16:55:00 -0700http://www.softstoryretrofitpros.com/blog/post/bargain-retrofits-the-ugly-truth-about-seismic-retrofits-in-los-angeleshttp://www.softstoryretrofitpros.com/blog/post/bargain-retrofits-the-ugly-truth-about-seismic-retrofits-in-los-angeles How thousands of low-quality seismic retrofit projects are being built across Los Angeles In the last three years, I’ve had the opportunity to work on several seismic retrofit projects with my company ‘Soft-Story Retrofit Pros’ and we’ve built numerous retrofit projects that we feel confident about. But when I take a look at other soft-story buildings being retrofitted I often notice shoddy work and lots of damage like termite damage or dry rot that is left in place, completely disregarding the need to repair all these wood-frame elements. Bad-quality retrofit project in West Los Angeles, CA. When the city of Los Angeles passed ordinance 183893 it did so in an effort to avoid what occurred during the 1994 Northridge Earthquake, when several vulnerable apartment buildings collapsed. Several property owners opposed the passing of the retrofit ordinance because they did not understand its true purpose, oftentimes describing it as an ‘undue burden’. When it came time to design and build their retrofit projects, these same property owners started to look for a “deal” and hired the lowest-bidder, and just as I’ve always said “paying less means doing less”. Careless contractors will simply cut corners and will use low-quality materials to ‘save’ the customer money – but is paying for a second-rate solution really a bargain? Deferred Maintenance One of the most common issues I encounter when inspecting a property is ‘deferred maintenance’. Buildings that have not been maintained properly will often have waterproofing issues on the roof or along the edges of balconies that contribute to the damage in the building’s wood frame. Over time cracks form in the stucco that if not repaired correctly, can cause prolonged water exposure. Just the other day my team inspected a property in Canoga Park that had a large vertical crack that was 1.5 feet long and 2 inches wide that was carelessly repaired with some type of latex caulking, an inappropriate solution for a crack of this size. This exemplifies the condition of most apartment buildings in Los Angeles. They suffer from water damage, dry-rot, and termite damage. These conditions cannot be ignored when these properties are retrofitted but unfortunately, this is not the case, I have seen too many retrofit projects that utilize heavily damaged beams and floor joists. Close-Up of Termite Damage & Dry Rot Save More=Do Less An apartment building right next door to my West Los Angeles Retrofit Project caught my eye one day. The three-story property was built in 1959, has 10 units (23 bedrooms/19 baths), and features open tuck-in parking in the rear with covered garages in the front. Online records indicate that the building has 13,000 sq ft, the building is heavy and will experience severe seismic forces during a large earthquake. The company that was doing the retrofit work (which shall remain nameless) encountered severe termite damage on the existing wood beam to which the cantilevered columns were to be connected, instead of repairing this issue, they chose to ignore it and connected the columns to this compromised beam. At this point I expected the city inspector to raise this issue and insist that corrections be made, but to my surprise five days later the installation had been approved and the front of the building was already covered in new stucco. Issues like these matter because they can have potentially dangerous repercussions, that company did not give their customers a “good deal” instead they did them a disservice. Aerial-Shot of the Three-story Apartment Building. Due to the fact that damaged wood-frame members need to be repaired or replaced, the price for a seismic retrofit project increases. But many retrofit companies that promise to save their customers money can only do so by ignoring issues like these. This can have potentially dangerous repercussions in the event of an earthquake, It could cause a failure of whichever retrofit solution is used. Several property owners I have spoken to tell me I quote them a price that is more expensive than the competition ...and I respond “That Doesn’t Surprise Me”. It doesn’t surprise me because other retrofit contractors just don’t do as much necessary repairs as my firm does, simply because repairs are not required by the retrofit ordinance. I don’t like to do the “bare minimum” and just comply with the ordinance - I like to do the best work possible and do whatever is necessary to make a building safer. My Promise To You When I take on a new retrofit project I promise each property owner to use the best of my abilities and collaborate with the best engineers to develop a retrofit solution that will perform as intended when it matters most - during an earthquake. There are now hundreds of retrofit contractors to choose from, but not all of them will give you the quality of work your property & tenants deserve. In closing, I want to reiterate that there are no cookie-cutter solutions when it comes to seismic retrofits - although similar, each building is unique and requires an individual solution. From the beginning, I collaborate with the best draftsmen & engineers to design and build a superior retrofit solution. Thu, 18 Jul 2019 15:03:00 -0700http://www.softstoryretrofitpros.com/blog/post/softstory-retrofit--los-angeles-retrofit-deadlineshttp://www.softstoryretrofitpros.com/blog/post/softstory-retrofit--los-angeles-retrofit-deadlines If you own a soft-story building in Southern California then you are well aware that the cities of Los Angeles, Santa Monica, and West Hollywood legally require seismic retrofits for soft-story buildings. The distinctive design of tuck-in parking on the ground floor makes soft-story buildings especially vulnerable during seismic activity, making them prone to collapse. The first kind of soft-story retrofit ordinance was passed by the city of Los Angeles in 2015, Santa Monica quickly followed suit in 2016, and West Hollywood joined the efforts in 2017. This year both Beverly Hills and Pasadena have begun to count how many at-risk buildings can be identified within their municipalities. Notice to Comply Notice To Comply letters began to be mailed by the city of Los Angeles in 2016. If you own a soft story building in Los Angeles that needs a seismic retrofit you should have received a notice letter in late 2017. Santa Monica has sent notice letters to the largest of buildings that require retrofitting (known as Priority I or Priority II) if your building has less than 5 units you should be receiving a notice letter later this summer. You have two years from the date you receive your notice letter to submit engineering plans to retrofit your property, or plans to demolish it. In Santa Monica & West Hollywood you must first submit a Structural Evaluation (a Structural Engineer needs to assess your building). A Seismic retrofit in Los Angeles is not something you’ll want to blow off. Southern California is notorious for the amount of seismic activity. A prolonged earthquake can cause serious damage to an already weak soft-story building, and the likelihood of a collapse is high. Prolonged shaking is what caused so much damage after the Northridge earthquake in 1994, it shook for over 15 seconds. This video below illustrates just how much damage can happen to an un-reinforced structure. The NSAID institute in Japan built a large-scale demonstrator Prolonged Seismic Movement Check out how 15 seconds of seismic movement cause the un-reinforced structure to collapse on itself. This type of prolonged seismic movement is what caused so much damage during the Northridge Earthquake. The design of a soft-story building is weak and is vulnerable during an earthquake, which can result in collapse and eventual loss of life. A building that has collapsed cannot be salvaged. You’ll have to demolish what’s left and rebuild. Full-Scale Shake Test Structural Evaluation You’re going to need a set of Architectural & Engineering Plans to submit to building and safety, no matter what city your building is located in. Los Angeles, Santa Monica, and West Hollywood all require engineering plans to be submitted as part of the Structural Evaluation. You’ll need a licensed Structural Engineer or an Architect to develop plans & calculations to determine if your building is sound. If it is found deficient you’ll need a plan to retrofit. The city of Los Angeles identified over 13,000 soft story buildings within the city limits that are considered weak and will need some type of retrofitting. Not sure if your building meets all the criteria to retrofit? We have access to the inventory list generated by the Los Angeles Department of Building & Safety, call us and we can confirm if your property is on the list. Unsure if your Santa Monica building is on the list? We also have access to the inventory list, we will happily confirm if your property is affected. -------------------------------------------------------------------------------------------------------------------------- Los Angeles Soft Story Retrofit Deadlines (Two years from receipt of Notice Letter) Santa Monica Soft Story Retrofit Deadlines West Hollywood Soft Story Retrofit Deadlines Beverly Hills & Pasadena Soft Story Retrofit Ordinances (Pasadena Now report on preliminary findings) Other cities are also considering passing retrofit ordinances, both the city of Pasadena and Beverly Hills have begun to study the condition of soft story buildings in their municipality. It is safe to assume that they will also follow suit by passing retrofit ordinances within the next five years. The Beverly Hills city council began talks of a soft story ordinance as far back as 2016. Although the ordinance has not been passed, their proposal is similar to that of Los Angeles. It would cover buildings that are of wood-frame construction, have two or more stories, feature tuck-in parking on the ground floor, and were designed prior to 1978. A preliminary count of buildings in Beverly Hills identified 300 buildings that might require some type of retrofit There are so many apartment buildings in Southern California that avoiding them is nearly impossible, and unfortunately, many of them were built before modern building codes were passed in the 1980’s. Tuck-in parking is a distinctive feature of soft-story buildings, it’s also the feature that makes them weak. A preliminary count of buildings in Pasadena identified over 400 buildings that might require a seismic retrofit. At a City Council meeting in May of 2018, Mayor Tornek is quoted as saying “We need to saddle-up and get this done”. Pasadena is expected to pass a seismic ordinance later this year with it going into effect in 2019. Don’t get caught off guard; If you own an apartment building in Pasadena you don’t have to wait until the ordinance is passed to retrofit your building. Our firm has been approached by property owners from Downey, Torrance, and Carson that are interested in getting their retrofit started this year. Soft Story Deadlines We recently hosted a free webinar in which we go over the deadlines to comply with the seismic retrofit ordinance of Los Angeles, Santa Monica, and West Hollywood. Want to Learn More? If you want to learn everything there is to know about soft-story retrofits you'll want to check out our most in-depth article What is a Soft-Story Retrofit? Everything You Need to Know About Retrofits on our new website. There, you'll be able to access all of our retrofit blog articles, case studies, our retrofit gallery, short videos, and enjoy free access to our full-length soft-story webinars. Our team has developed all this content for property owners like you. It is your destination to learn all about the retrofit process. Bay Cities Construction and Soft-Story Retrofit Pros is here to help answer any questions you may have about your retrofit project. Our team has the experience to Engineer & Build a Cost-Effective Retrofit Solution for your property. Get started today by visiting our website at www.softstoryretrofitpros.com to schedule a free assessment. About Us For over 15 years Soft-Story Retrofit Pros has helped hundreds of homeowners with their projects. When you hireRetrofit Pros you don’t just hire a contractor, you hire an entire team of Pros. With several years of experience, our team has the expertise to help you Design, Engineer, and Build Your Retrofit Solution. We also represent you City Representation when submitting your plans and ensuring they are approved, and we handle all the Permit Processing so you never miss a day of work. If you think Retrofit Pros is the right team for you, contact us today. We have the experience, knowledge, and know how to help you save time & money on your seismic retrofit. Ready to take the next step? We’re certain that Soft-Story Retrofit Pros is the best general contractor for your project, you can Schedule an Appointment by clicking HERE. We offer a complimentary One-hour consultation & assessment, so you can meet our team and we can discuss your Soft Story Retrofit project. If you have been disappointed by other contractors, it's time to call one of the best seismic retrofitters in Los Angeles. Fri, 28 Jun 2019 17:34:00 -0700http://www.softstoryretrofitpros.com/blog/post/pasadena-approves-seismic-retrofit-ordinancehttp://www.softstoryretrofitpros.com/blog/post/pasadena-approves-seismic-retrofit-ordinance Ordinance No. 7345 passes First & Second Reading. California is the land of many faults, earthquake faults that is. That's why so many cities in Southern California have recently passed local ordinances to require the seismic retrofit of vulnerable "soft story" apartment buildings. We now have another city that has navigated the gauntlet of public scrutiny and passed a mandatory earthquake retrofit ordinance, the city council of Pasadena officially adopted Ordinance 7345 on May 20, 2019. The ordinance is set to go into effect on June 24, 2019. Pasadena joins the city of Los Angeles, Santa Monica, and West Hollywood in passing a seismic retrofit ordinance. These types of laws stir up controversy and become political grenades, despite the fact that protecting structures to save lives is a good thing. Pasadena Ordinance 7345 In 2018 the city of Pasadena consulted with Degenkolb Engineers and the Structural Engineers Association of Southern California to develop the technical portions of the retrofit ordinance. The main purpose of the ordinance is to safeguard the public from the dangers associated with "soft-story" buildings during an earthquake, which were made evident by the Northridge Earthquake in 1994. The Northridge Earthquake caused the collapse of several apartment buildings that were built in the 1960's. The city estimates that there are 493 vulnerable buildings in Pasadena that will require some type of seismic retrofit. You can read part of the Pasadena Ordinance below. "The provisions of this Chapter are intended to promote the public welfare and safety by reducing the risk of death or injury that may result from the effects of earthquakes on existing wood-framed multi-story buildings with Soft, Weak or Open-Front Walls. Generally, this type of structure consists of partial tuck-under parking on the first floor level with living space in the floors above. In past earthquakes many of these types of structures have performed poorly and collapsed causing loss of life, personal injury, and substantial property damage. This Chapter creates minimum standards intended to reduce the risk of collapse and improve the performance of these buildings during earthquakes, but not necessarily prevent, the loss of life, injury and damage to property." The retrofit ordinance goes into effect on June 24, 2019 - if you own an apartment building in Pasadena our team can help keep your tenants and your investment safe in the event of an earthquake. Known faults across Southern California. I decided to attend the Pasadena city council meeting a few days ago to witness firsthand the public process of adopting such an ordinance. I was impressed by the level of professionalism and decorum exhibited by the council and city officials. The entire meeting lasted about 4 hours as they covered several other topics. I did take the opportunity to voice my concerns about the shortcomings of how the seismic ordinance was executed in Santa Monica and Los Angeles. I filled out a comment request card and was called out to speak during the public comments portion of the meeting. Each speaker is given up to 5 minutes to comment and voice their thoughts and concerns. It was fortuitous that I got to chime in, but I was fascinated to listen to what other residents and stakeholders thought about the proposed ordinance. Watch Alexander Rodriguez of Soft Story Retrofit Pros | Pasadena Passes Seismic Retrofit Ordinance Other than my own comments in support of such a measure, all other public comments about the seismic retrofit ordinance were in opposition. One after another, each resident detailed why the ordinance should not be passed. I could not help but reflect on Dr. Lucy Jones’s book, “The Big Ones.” She talks about the dynamic of ‘communal amnesia.’ How can we forget the damage, destruction, and loss of life due to the Northridge Earthquake? The earthquake only lasted 12 seconds and it produced $40 Billion in damage, death and caused the displacement of hundreds of Angelinos. It has taken 20 years for our government to develop the political capital to commence the process of making California cities more resilient. The law is not perfect however Pasadena will be better off because of it. I can only hope that Pasadena will not commit the same mistakes that Los Angeles and Santa Monica have made. Next week my team and I will be attending the public hearing in The City of Glendale as they also commence the path of seismic strengthening. Got any questions? For those of you that don’t know, I am writing a book on soft story retrofitting. Please sign up for our email newsletter and blog article notification. You will have the opportunity to download it for free and maybe even get a signed copy. The mission of this website is to educated people about soft story retrofitting and the importance of a resilient community. Help us spread the good word by sharing our message. Your comments are a major part of how knowledge is spread, don’t be shy to comment below! Fri, 28 Jun 2019 15:46:00 -0700http://www.softstoryretrofitpros.com/blog/post/making-soft-story-buildings-perform-what-about-more-lumberhttp://www.softstoryretrofitpros.com/blog/post/making-soft-story-buildings-perform-what-about-more-lumber Adding more lumber is the key. Adding more lumber is the key. It’s been four years since the Los Angeles City Council passed Ordinance 183893 back in 2015, and since then thousands of apartment buildings have been retrofitted. Since then my team has only retrofitted a handful of buildings in West LA, but I’ve seen over 100 sets of plans to bid on and frankly, some of them do not pass muster. While all of these plans include the use of heavy structural steel, the majority of them do not include the use of diaphragm framing or the addition of lumber to reinforce the existing wood-frame. Seismic Retrofit Project in West Los Angeles In this article, I want to cover some technical topics of soft-story retrofitting so that engineers can develop stronger designs and avoid some common pitfalls in our industry. For those of you that don’t have an engineering background, don’t worry I will break things down in laymen’s terms. For those of you that want to read more of my work on soft story retrofitting make sure to visit my website at www.softstoryretrofitpros.com/blog I created this website to be a resource and online learning center for those looking to learn more about seismic retrofits for ‘soft story’ apartment buildings. ‘Principles of Physics’ Approach For many engineers, architects, and contractors alike soft story retrofitting is a dive into uncharted waters. We need a methodology for making decisions when the correct path is not always clear. In environments with many unknowns, physics ‘first principles’ approach dictates that a hypothesis and methodologies be based developed from the foundations of known truths. In the case of soft-story structures, we should start with the current condition of the building in question. If we do not know the condition of the building’s lumber, how we can determine how much more lumber will need to be added to the building in order to adequately transfer seismic forces to the new structural steel members (moment frames, cantilever column, steel shear walls) that are being installed? This article will cover the lumber aspects of the retrofit. You can see our other soft story articles to learn about steel hardware and connectors. A mistake that 90% of people make Over 90% of the retrofit projects I have seen get off on the wrong foot – they do not remove stucco before construction. The common mistake is that the stucco is not removed in critical connection sections that would otherwise allow engineers to see the condition of the existing wood members. Engineers, architects, and contracts alike make the mistake of overlooking this simple step. We went through this experience on our very first seismic retrofit project in Los Angeles, we did not remove stucco during the design stage and only removed it once we launched our project. The pictures below illustrate the importance of the designer and contractor to understand the existing site conditions of the buildings’ lumber. This is our soft story project in Harbor City, Los Angles, and it just so happens that this section is where a large plywood diaphragm component is to be installed. As you can see the floor joists have been exposed to years of water damage and the rim joist shows signs of exposure to water over the years. In this case, additional lumber was necessary to create load paths necessary to transfer seismic forces back to the moment frame. water damaged wood-frame The original design called for A35 framing angles to the subfloor and 2x lumber blocking for sheathing diaphragm. When you understand that seismic forces will make the floor joists deflect like piano keys under Elton John’s fingers, you realize that more lumber is necessary! A35 Framing Angles seismic forces The forces that the dragline will face are 3 dimensional. The retrofit ordinances and building codes do not require much but an earthquake is a violent force of nature. With that said, the matter requires that we take a serious and extensive look at how to best strengthen the building’s structural wood members. Adding connectors is not enough because the wood will not hold – it will fail. Adding lumber in combination with connectors can help create reliable load transfers. This conversation triggers the question of how much will this cost? I have written other blog articles about cost and you can find them on our BLOG BY CLICKING HERE. The discussion about cost is premature because, without a viable design, a cost is just a hypothetical number. Talking about the cost before opening up the building and assessing what you are working with is baseless. The second trap about discussing price prior to design is that an engineer may start to design towards the cost of construction instead of designing under the purity of math and physics. Of course, the cost is important just don’t let it be the primary factor. Remember that our loyalty in design and construction must be towards the desired outcome, a safer higher performing building! Below you will see pictures of how much more additional wood was added to the diaphragm section. In some sections, the footprint of the diaphragm was expanded. This is a diaphragm section that I had our carpenters pull out the 2x blocking and replace them with 4x 12” material. new solid blocking added Creative Solutions Ultimately, we installed additional lumber and attached Simpson HSLQ heavy angles along the entire length of the wall. Understand that this section of wall will experience tremendous force during a major earthquake. More lumber tactically placed in this area can make a big difference in the performance of the building. The above pictures represent an additional $6,000 of labor and materials. The tradeoff, you have a predictable load transfer of up to 40+ kips. There are sections of the retrofit that you must add the lumber necessary to add a degree of redundancy and predictable load transfer. Structural Engineers cannot just rely on mathematical assumptions regarding load transfers. The designer must add lumber in certain sections in order to create a higher level of certainty that the loads will transfer to the new steel (SMF, Cantilever column, shear walls) components. Take into account that this can only be done by creating redundancy to the existing transfer paths with the addition of new lumber. creating a path for seismic forces Many soft story designs rely on existing subfloors that are assumed to be in acceptable condition. The fact is that seldom is this the case. Existing 1” x 6” diagonal subfloors have often experienced substantial damage over the years. The nails are often rusted or deteriorated by more than 50% and the wood has large knots. These types of subfloors should not be given much value towards load transfer values. Designers should field verify these types of subfloors. When 1 x 6 subfloors are identified, designers should consider a prudent amount of plywood sheathing in the tuck-under parking area. When using shear walls at the perpendicular, consider using 4x horizontal load transfer pathways. Heavy lumber like 4 x 16” lag bolted to floor joist can transfer 27-54 kips along return draglines. It is an easy and less expensive technique that can be done in a smaller footprint. common frame conditions Below represents how to install 4x horizontal. The strong walls will then be attached to them and a predictable load transfer can occur. In the scenario, the lumber has a compression strength in excess of 27 kips per bay. This also allows precise 90 degrees alignment with the moment frame. new framing Below you can see a technique we used to get tremendous force resistance in a small footprint. Once the floor joist bays are filled in with 4x horizontal, the shear walls go in. This technique helps make it easier to line up the shear panels with the existing column. You can achieve a 40-50 kip transfer path with just 2 bays! innovative use of Simpson Strong-Wall shear panels Avoid Charlatans Back in 2017, I was approached by an engineer that boasted doing hundreds of Soft Story retrofit designs; under the pretense of ‘value engineering’, he bragged and said his designs were efficient and the contractor would not have to shore the building. Let me tell you that when battling earthquake forces, value engineering just means, doing less! Wisdom prevails when prudent measures are taken to evaluate the entire system along the immediate dragline area. I am not talking about opening up other areas of the building that do not fall within the scope of the soft story retrofit. However, if there is evidence of structural deterioration regardless of location. It is prudent to properly verify and evaluate all the connections on the draglines were the retrofits are being done. In this case, the existing concrete pad was only 8” thick in some areas. ShakeOut Scenario - Los Angeles, Detailed Perspective Understanding the regional seismology make us better The USGS has published several papers on earthquake ground motions. A deeper understanding of how the ground will move and which faults are the greatest threats helps shape how engineers create seismic retrofit designs. Dr. Kenneth Hudnut Ph.D at USGS gave a tremendously informative talk at a TownHall Los Angeles event. As part of his presentation, Dr. Hudnut showed us a computer-generated model of ground movement and heat mapping of the forces. It was truly eye-opening to see how much the ground will rise and fall as the seismic waves travel through a region. Watch the video above. Understand that the dragline will experience violent tension and compression as the S-waves pass through the building. According to the USGS earthquake 'Shake Out' Scenario models, the ground makes experience significant uplift and drop as S-wave travel through the soil and building. It is plausible for the ground to lift and drop 2’- 3’ during the strongest portion of the seismic movement. All foundation members along the dragline should resist force at a prudent level. Dragline Beam Connection: A New Understanding Dragline Beam Connection: A new understanding This section will receive violent forces and the code is not enough: deal with it! Add more lumber, heavier lumber. Build redundant transfer load paths with defendable connections on each axis. Understand that earthquake may come from one of the following 3 faults. What does this mean for the structure? It is important to work, with lives and livelihoods of over 250,000 residents at risk. This is serious business with a lot at risk. It is our duty and responsibility to use all of our talent, wisdom, and experience to make these really poorly built buildings perform! It is a challenge that is both noble and worthy. Seldom in our careers do we have the opportunity to engage in such impactful work. Do not be discouraged by the penny pinchers, focus on those that are interested in quality and performance. As Seth Godin would say, “shun the non-believers.” With that said, go to design something amazing today! Thu, 13 Jun 2019 16:26:00 -0700http://www.softstoryretrofitpros.com/blog/post/los-angeles-softstory-retrofit-best-practices--building-wont-fall-building-wont-breakhttp://www.softstoryretrofitpros.com/blog/post/los-angeles-softstory-retrofit-best-practices--building-wont-fall-building-wont-break Not all retrofits are created equal - see how we build BETTER retrofit solutions. As a retrofit contractor that specializes in soft-story buildings, I see lots of engineering plans that have been designed by other companies. Every day property owners send me their drawings with the intention of getting a construction quote, they want to know just how much their soft-story retrofit will cost to build. Sometimes I have to be the bearer of bad news - I can't tell you how frustrated they get when they find out that their plans will not work as designed. Their plans have a series of shortcomings, they won't do enough to protect the structure in the event of a major earthquake. The most common issue we see time and time again is that not enough attention is being focused on the existing wood-frame members; many of these buildings are old and have not been maintained properly which causes damage to the existing wood frame. In this latest blog article, I will discuss one aspect of soft-story retrofit design that is being ignored ... the existing wood frame. Design Flaws? So just what do I mean? Most of the engineering plans have strictly focused on the size and strength of the steel being used in the proposed solution (OMF/SMF moment frame, or OCCS/SCCS cantilever column). Seeing a huge steel column/beam being installed in your building can give you a sense of security, even if it's not designed properly. Installing steel is the easy part, designing it to perform properly is hard. Unfortunately, I've seen lots of ill-designed retrofit plans that are flawed - and I fear they will do more harm than good. The flaws are in the absence of reinforcing the existing wood frame, specifically the floor joists. The heavy steel that is installed is a stiff element, that can crush the aging wood frame. If you do not strengthen the existing wood members, they will buckle when severe seismic forces push them into the stiff steel. It takes a careful eye and tons of experience in wood-frame construction to design a new structure that transfers seismic loads correctly. Would it shock you if I told you that 95% of plans do not address this issue? I've seen projects where nothing is done to the existing wood frame. Why does this matter? The building will not perform correctly - in the event of a large earthquake, the building could collapse! That's right, all the money you spent on your seismic retrofit goes down the toilet. The "value-engineering" solution you paid for did not protect your building. The building will suffer massive amounts of damage that could have been avoided, mostly caused by the fact that the seismic loads did not transfer correctly. It is a systemic design flaw created by a void in the Santa Monica and Los Angeles City soft-story retrofit ordinances (more about that in another article). New structural hardware installed. New Connections Developing a comprehensive retrofit solution requires the reinforcement of the existing wood frame - this includes adding structural connections like Simpson Strong-Tie LTP4/LTP5 and A34/A35 plates. Creating a rigid structure that transfers seismic loads correctly will ensure the building can perform during a significant earthquake. Here is one way to fix your engineering plans. Once the stucco is peeled back and the building is opened up, a trained eye must assess where the building is structurally weak. The picture above was taken at our seismic retrofit project in Los Angeles, the area in yellow is where we put in more small steel connectors like Simpson Strong-Tie LTP 4 connectors over the new blocking. Other contractors do install this type of hardware, but in my opinion, they don't use nearly enough of them. The yellow squares represent the area that must be blocked with 4" x 12" lumber. This will create a blocking system that will help the subfloor resist torsion and will tie the floor system to the existing dragline beam (the opening where the cars enter the garage). New Special Moment Frame & framing system. Systems Working Together In the picture above we look at the wood blocking (in green) that we installed above the Steel Moment Frame. This "solid" connection allows the seismic forces to transfer between the existing building and the new special moment frame. The next step is to run that blocking along the entire length of the buildings. This creates more contact points between the old and the new structures, allowing them to work together, instead of against each other. A larger footprint increases the likelihood that the seismic forces will transfer correctly back to the steel moment frame. This is what our team tries to design, a superior seismic solution that is strong enough and smart enough to protect the soft-story structure in the event of a significant earthquake. New lumber is needed to strengthen the building. Our Philosophy This requires a tremendous amount of lumber and the knowledge to know where to put it! Here is a picture of half the lumber required to make this load transfer possible. Retrofit Pros follows the philosophy, "building doesn't fall, building doesn't break", we build better & smarter solutions that perform when it matters most. We are loyal to the building - we asses each one based on their current condition and strengthen them accordingly. That does not mean that the buildings will be 'earthquake proof' but it represents our obsession with making the building stronger and safer. If you keep head straight and focus on the building, you will not fall victim to the follies of "value engineering" which simply translates into 'do less and make it cheaper." This mentality ultimately leads to poor retrofit design! What do you think about this article? Post your comments/questions below. New and stronger framing. Mon, 01 Apr 2019 16:00:00 -0700http://www.softstoryretrofitpros.com/blog/post/unintended-consequences--the-systemic-misuse-of-the-cantilever-columns-may-affect-thousands-of-soft-story-buildingshttp://www.softstoryretrofitpros.com/blog/post/unintended-consequences--the-systemic-misuse-of-the-cantilever-columns-may-affect-thousands-of-soft-story-buildings Will the LA Retrofit Program have unintended consequences? As we enter the fourth year of the Los Angeles soft-story retrofit program, some of the most prominent Structural Engineers (SE & PE) are asking themselves “What the heck is going on?”. There has been a recent trend amongst engineers that are working on soft-story retrofits by using Cantilevered Column Systems (CCS) on apartment buildings of all sizes, often misusing them. Many retrofit contractors promise owners thousands in savings by using Cantilevered Columns instead of a Moment Frame system Rampant Misuse of CCS The cantilever column was developed to be a “stop-gap measure”, intended for it to be used only in soft-story buildings that have irregular, narrow, and hard to retrofit areas. But they have now become the primary retrofit solution for hundreds of buildings in the last 12 months. Of all the engineering plans I have seen in the last year, over 95% of them use a cantilevered column solution. But many of these plans fail to consider the deteriorated state of existing wood-frame members. Not all apartment buildings that require a seismic retrofit are maintained properly; when I perform a Retrofit Assessment, I often find termite damage, water damage, and dry rot. Many of these properties are under rent control, and sometimes owners feel no motive to perform thorough maintenance on their building. With all that said, the fact of the matter is that some of these designs may exhibit a critical flaw that might, in turn, cause a tremendous amount of avoidable damage to the existing wood-frame structure. I don’t want to create a panic, but we all need to know what type of plans are being submitted to the Department of Building and Safety (LADBS). My goal is to spread awareness about the misuse of a viable retrofit method (cantilever columns) and how some buildings with these systems might sustain damage during a major earthquake. I am voicing my concerns over a system that I have seen implemented incorrectly, I am not bashing retrofit contractors or structural engineers that work on these systems. Unsure of what a Cantilever Column System looks like? Check out this sketch below. Engineering detail of a cantilevered column. Los Angeles Soft-Story Retrofit Program The soft-story retrofit industry is fairly new, San Francisco passed their mandatory soft-story retrofit program in 2013, and Los Angeles followed suit in 2015 by passing ordinance 183893 and 184081. But it is still new enough that some mistakes are bound to be made. The soft-story retrofit market has been flooded by a tremendous amount of new design & build companies. Have you been approached by them? There are so many new contractor companies being formed, they are literally coming out of the woodwork. These “design-build” firms have taken the majority of the seismic retrofit engineering work away from well-established engineering firms. Traditional engineers have a operate on a mindset that can be described as “make the building perform better”. But these new players promise value-engineering that can be described as “make the construction cheaper” to entice property owners. This value-engineering mindset can be described as “make construction cheaper, and it sends engineers down a path of ‘how to do less?’ As a result, many property owners have been pitched the Cantilever column as a primary engineering solution under the pretense that it has a lower construction cost when compared to a traditional solution like a Special Moment Frame. Steel is strong, and these cantilevered columns can withstand strong seismic forces, but nothing is being done to reinforce the existing wood-frame structure. Unfortunately, the business practices of a few retrofit contractors and engineers have led property owners down the wrong path. Where are the Experts? SEAOSC is the Structural Engineers Association of Southern California, but very few people outside of the industry know who they are. Not many SEAOSC member engineers (the real subject matter experts) are participating in the residential soft story engineering market because engineering prices have plummeted to unprofitable levels. These well-established engineers work on large seismic retrofit projects that require technical expertise, they’ve worked on retrofitting buildings like Los Angeles City Hall. The irony is that SEAOSC members are seismic experts in both wood-frame and steel-frame construction, but not many people are approaching them for soft-story retrofit work. Their expertise and contributions have helped municipalities develop soft story retrofitting criteria. These experienced engineers should be the only ones developing retrofit plans because they are the true retrofit experts. Unfortunately, not many people property owners are seeking the help of these experts and are instead seeking the help of individuals that can develop their retrofit plans for $3,500. These engineers are desperately needed in the execution of the ordinance. They must be the ones who hold the line and prevent any unintended consequences that might arise from this well-intentioned ordinance. SCCS & OCCS Uses Who Will Be Impacted? When the City of Los Angeles and the City, Santa Monica, and West Hollywood passed their respective soft-story retrofit ordinances, the intention was to make the structures safer by preventing building collapses, using a life-safety standard. An additional benefit would have been to improve the City’s resilience (getting back to normal) after a major seismic event. There are an estimated 150,000+ housing in soft story structures in the City of Angeles [1]. If these buildings are damaged and or red-tagged by a major earthquake, thousands of low-cost housing apartments would be immediately off the market. Those tenants would have no place to live, and the property owners would be left unable to collect rent. I believe that the market forces that reduced the price of construction have also derailed the noble intentions of the soft story ordinances. It is really important that Los Angeles and neighboring cities get this effort right. In the event of a major earthquake, everyone will be impacted, but nobody will have it as hard as residents living in a soft-story building that has not been retrofitted properly. 21-inch steel bucket connection The second issue I have noticed deals with steel-to-wood connections; cantilever columns have a small connection (surface area) to the existing wood members of the building. This narrow connection footprint creates the possibility of tremendous stress to develop overs in a small area. Very few cantilever designs in buildings with dragline span larger than 20’ have sufficient transfer area at the perpendicular. You don’t have to be an engineer to realize that the kinetic energy of a 150,000+ lbs experiencing seismic movement will not transfer into the cantilever column’s 18”-20” post cap. Because many carports have side walls, no requirement is triggered for perpendicular retrofit or reinforcement. This becomes a problem in draglines with spans larger than 30’ because the building will experience first-story rotation, causing perpendicular pressure on the dragline wood beam. The wood beam and its installation were never designed to deal with such a scenario. With the exception of Special Moment Frames, steel I-beams require bracing. Knowing this dynamic, why would anyone allow a cantilever column to be installed on a wood-frame dragline beam with minimal transfer surface area and exposure to perpendicular force? Water damaged subfloor In the hundreds of buildings that I have inspected, existing floor joist are deteriorated by exposure to moisture due to toilet and bathtub seal leaks (the subfloor is in no better condition). The existing wood framing systems will also need to be strengthened as part of the retrofit. The goal is to expand the footprint of the transfer connection points in order to improve the likelihood that the Cantilever Column will perform as intended. Failure to do this will cause the existing, brittle wood members to be crushed as they are thrust into the newly installed heavy steel members. We have to refocus our efforts on creating a durable and resilient retrofit. "But the City Approved It" When I tell property owners that the retrofit solution they asked me to bid on is not strong enough they always reply with “But the city approved it”. It is foolish to think that contractors and engineers involved in these flawed designs will be sheltered from any liability because the design complies with the city ordinance. The same owners who are pushing for cheaper construction cost will immediately turn on their contractor and engineer once they realize that there is a flaw in their retrofit and lawsuits will ensue. We must proceed with caution and asses each building on its own attributes. Contractors providing free estimates and engineers providing free assessment may actually be a detriment to prospective clients. When we are paid for our time, we can dedicate time to properly look at the macro and micro issues affecting our Clients’ buildings. Perhaps it is time we reframe how we as professionals approach these types of projects. As a licensed contractor for 15 years, I have committed to the improvement of my calling and life’s work. I am both excited and cautious as an active stakeholder in making Los Angeles a safer city. What do you think? Do you agree with my Cantilever column thesis? [1] Ali Sadre, SE (n.d.) Soft-Story Residential Buildings: A Statewide Perspective on Collapse Risk https://www.burbankca.gov/home/showdocument?id=2461 Thu, 14 Mar 2019 11:33:00 -0700