Should I Retrofit My Home?
After the July 4th earthquakes in Ridgecrest Ca (west of Bakersfield, Ca), there were 34,091 overall earthquakes documented (information from the USGS website). We were inundated with phone calls from homeowners asking… “Should I retrofit my home?”
The primary purpose of earthquake retrofitting is to keep your home from being displaced from its concrete foundation. By displaced, I mean it can slide off your foundation or cripple walls can buckle and collapse, just to name a few.
Almost any house built before the 1980s can be improved in such a way as to reduce earthquake risk. Even some houses built in the 1980s can be improved. Houses built 1990 or after usually have the earthquake resistant features installed during the original construction.
“How do I know if my home has been retrofitted?”
If you go down into the crawlspace and look at the areas between the first floor and the foundation to find out if your home is bolted to the foundation.You’ll be looking for the heads of the anchor bolts that fasten the sill plate to the foundation. The sill plate is the wooden board that sits directly on top of the foundation. If it is, you should be able to see the large nuts, washers and anchor bolts, installed at least every 4 to 6 feet along the sill plate. Steel plates are sometimes used instead of anchor bolts.
“What is the process of retrofitting a home?”
During your foundation inspection, we would measure the home to scale, take pictures of the outside of the home that shows the front having both sides of the roofline visible, both sides views and the back.
Our Project Consultant would access the crawlspace, and inspect it’s overall health. He would inspect all of the posts, concrete pads and beams to make sure they have not started to deteriorate. He will also make sure that our crew will have the necessary clearance needed to get the work done.
We install, every 6 feet, a UFP plate (Universal Foundation Plate). This plate attaches the sill plate to the foundation using screws and anchor bolts making the building safer and less prone to major structural damage during an earthquake.
A permit would need to be obtained from the local building department prior to doing the work. They do require a detailed drawing, and most times, they will accept our drawing. In some cases, they will require the drawings to be done by a structural engineer.
“Are there any financial benefits to doing a retrofit?”
Most insurance companies will offer a discount on your policy for retrofitting your home.
Also, the city of Los Angeles has the Earthquake Brace & Bolt Program. This program helps with the cost of the retrofit.