Posts Tagged ‘Seismic retrofitting’

Seismic Retrofitting Facts

Author: The Editor

Seismic RetrofittingSomeone tell me – what exactly IS a “retrofit” – does it make my home safer? Why should I bother? Isn’t my house already “bolted”. . . ?

 

Merriam-Webster’s definition: “retrofit” – to provide (something) with new parts that were not available when it was originally built.

– To furnish (as a computer, airplane, or building) with new or modified parts or equipment not available or considered necessary at the time of manufacture.

Dictionary.com definition: – “Retrofitting” – to install, fit or adapt (a device or system) for use with something older: “To retrofit solar heating to a poorly insulated house”.

So what is seismic retrofitting for your home?

Seismic retrofitting is the process of adding additional hardware, plywood and framing lumber to the foundation area of a building in a way that heightens its readiness and helps protect it during seismic activity. There are very specific methods of how this is to be done and unfortunately many wrong ways to do it as well! If your house is built later than 1936, it almost certainly has some level of “bolting” in place from when it was first built. Standards have of course evolved tremendously since then (imagine the lack of safety features in a 1936 car compared to a current one!) and this is where seismic retrofitting (bolting) comes in. It is employing current structural knowledge into an otherwise antiquated situation to improve its overall ability to help withstand earthquakes and to help protect you from catastrophic loss.

We perform full seismic retrofitting (“house bolting”) to current standards. The exact specifications of this work can be viewed directly via the City of Los Angeles website at www.ladbs.org. Even if you do not live in Los Angeles itself, all cities that we work in recognize the Los Angeles standards and accept them. This includes, but is not limited to Glendale, Burbank, West Hollywood, Beverly Hills, Pasadena, South Pasadena, Santa Monica, Culver City and the list goes on.

We also perform corrections of incorrectly performed or antiquated bolting jobs in order to help protect those homes from future earthquakes. (Statistic: 85% of homes within various cities of Los Angeles county that have been “bolted” since the 1994 Northridge earthquake had the work performed sub-standardly when it was done.) Therefore, only about 15% of the inspections we perform find houses to be properly and fully retrofitted. This includes houses that have been “retrofitted” after the 1994 Northridge earthquake. If your foundation retrofit is sub-standard in some way, we will be able to provide you a recipe for correction to resolve that deficiency and help protect your home from loss in any future earthquakes.

If you’ve not already done so, feel free to call for a complimentary

inspection of your primary residence and at the same time, we would let you know specifically (if anything) is lacking when compared to the current standards that are available!

 

Is That Holding my House Up?

Author: The Editor

Yes, this is yet another “double-take” moment under a house where just when I was sure I’d seen it all, this…”assembly” came into view! As is often the case, the homeowner had no idea that this was underfoot and in fact this pile of scrap wood is in a location that made it very relevant to the two-story weight load above it!

Now, the good thing is that this is a very limited problem and a very limited repair, but the bad thing is that this makes this home very vulnerable seismically and so many such simple fixes (this is a few hundred dollar type repair) can be eliminated quite easily.

We pride ourselves on finding and eliminating the worst offenses as a means of adding stability to a building as well as helping to extend its overall useful life. In that we offer a free foundation inspection for an owner occupied primary residence, feel free to pass this e-mail on to anyone who may have questions about the foundation of their home. Hopefully we can give it a clean bill of health but if there are issues to correct, we can let them know the best way to go about taking care of them as well!

Over the years, I’ve inspected countless thousands of foundations and one of the most frequently asked questions I’ve heard from homeowners’ is this: “Do you think I should bolt the house?”  Well now being a foundation contractor, any answer from me could certainly be viewed as being biased by virtue of what would seem to be a distinct “conflict of interest” on my part, as seismic retrofitting (house bolting) is a service we offer!  It can present itself as somewhat of a “Catch-22” in that if I answer that “Yes, it is a good idea”, I look biased. If I answer that “No, it is not needed”, I may be doing them a great disservice in that there may be things that the house needs to better prepare it seismically. With that dilemma in mind, I have evolved a simple analogy that educates them such that they can then participate in the decision process. Quite simply, the most logical analogy I’ve found and the one that resonates with the majority of homeowners is simply this: house bolting is similar to putting on a seatbelt when you’re in a car; in the event that the car is in an accident, the chances of injury are much less than if one were not wearing a seatbelt and yet even a seatbelt cannot ensure that one will walk away injury-free. Well house bolting is essentially the same thing; a house that has had proper seismic retrofitting done to it has a much better chance of performing well during an earthquake, but also does not fully eliminate the potential of damage to the home.

The other key factor to consider, holding to the analogy above, is that technology evolves. The safety features in say a 1960’s car versus the safety features in a new car have very little in common; the “lap belt” has been replaced with shoulder restraints, air-bags, side impact protection, anti-lock brakes, crumple zones, etc, etc, etc.  As that relates to house bolting, the same is true of how well an older structure is secured versus a newer one.  Cars from the teens, 20’s, 30’s, 40’s, and 50’s primarily had nearly nothing that we have today in terms of safety!  Seismic retrofitting has been on a similar evolutionary journey, with the latest technology offering the most benefit.

It is most often true that the older the home, the more it will benefit from seismic retrofitting.  The only real reason to have house bolting done to a house is to prepare it for an earthquake; no earthquake, no house bolting needed. No car wreck, no safety features needed…  Though it is a personal decision, most people realize that just as driving around without contemporary safety features is not ideal, neither is hoping that their house is able to withstand the forces of Mother Nature should the time ever come.