So now the CEA is wrong?
And the California Seismic Safety Commission as well?
Did you even read the reference?
"I don't care to do the work for the OP"
Sounds like a case of "declare victory and quit".
"I have other problems that need my attention."
Yeah, like your biggest one....... you don't know when you're wrong.
But you sure can tap dance.
The behavior of bolts in concrete is not the issue here, it is the
existence or non-existence of them.
It's binary thing (look that up it you don't know what it means)
"If the CEA doesn't seem to care about their behavior in
"seem"..... more weasel words?
FYI .......... the CEA & CA SSC are doing just fine without your
I thought I was a waste of your time?
Why do you keep posting replies of no substance and never address the
issues or questions?
Yeah, I happen know, from direct knowledge, that the OP is doing just
Now you're telling the OP what he "needs to do"?
You keep posting non sequiturs.
You were wrong & won't admit your error but the weasel worded nonsense
keeps on coming.
I happen to know that the OP already has the answers he needs.
He got answers from you? ........ the other end of the horse.
More links that might convince you
Short answer....yes your home is bolted to the foundation.
If you want to learn more
Here's a book & website I recommend...
If one examines the homes, other residential & commercial building
that were badly damaged by earthquakes one can get a pretty good idea
of what works & what doesn't work.
Take a look on the web for residential structural damage from
Sylmar (71), Whitter (87), Loma Prieta (89), Big Bear / Landers (92),
The need to simply "bolt the house to the foundation" was pretty well
know in California since the early 1900's.
The point was made again by the 1925 Santa Barbara and 1933 Long Beach
(actually closer to Huntington Beach) earthquakes.
Despite these "reminders" the requirement for mere mud sill bolting
did not become nearly universal in CA until after WWII.
How much risk (financial & physical) you are exposed & whether e/a
insurance makes sense depends on a number of factors.
Type of house construction; style of house, age of house
Location of house
E/Q insurance coverage / deductible
If you've got a reasonably sized (small or medium), single story home
you'e probably at low risk.
Not bolted ...higher
Unreinforced masonry (URM) chimney ....higher
Dry wall..... nuetral
Plywood shear walls (not likely in 1948) .... lower
expanded metal lath & plaster .... lower
open cailfornia style floor plan ....higher
lots of small room .....lower
lots of big windows..... higher
smaller widows ... lower
My house (1-1/2 story w/ tall URM chimney) was built in 1930 in
central Orange County, not bolted (gotta get that done)
but survived (with some cracking) all the post 1930 e/q's in SoCal.
Fortunately, central OC is a lower seismic hazard area
I carried e/q insurance for a while after 1987 quake but premiums kept
rising along with the deductible so I let it go.
btw the mud sill bolts were a provision to keep the house from
"walking off the foundation" in an e/q.
This failure mode caused a lot damage in
Hold downs mentioned in some of the other posts serve another purpose.
They are typically part of an engineered "lateral system" that is
designed to resist "lateral" (side to side) forces.
Hold downs & shear walls work together.
Bob, back when I designed the apartments, the building dept would not
allow simple bolts to resist earthquakes. I don't know if the same
applies to homes but the OP can take pictures and show his local
building department and let them answer the question. I suppose he
could also ask the insurance company / agent the same question.
The OP's original question was
........From the photos in this link, does this mean my home is
"bolted to the foundation"? ..........
The answer to this question is "yes".
As I posted previously.... the aim of "foundation bolts" were to
keep a house from "sliding" or "walking" off the foundation.
They represent a first step in resisting the forces generated during
I know of no regulations that require a homeowner to retrofit an owner
occupied single family residence.
Codes change over time. A home will be "not to code" as soon as the
The OP has an existing home built in 1948. Depending on it's design
and construction it could be more e/q resistant than a more "modern"
The Sylmar (1971) e/q was another wake up call for "lateral force"
Multi-family units fall under different runs than single family homes.
No, you are taking his question out of context. He's concerned about
Yes, in a non-earthquake zone.
I don't know his local building code so I can't comment on this.
Strictly as a "guess", I tend to agree with you just based on my
experience with other locations.
Sometimes. From what I've read in general over the entire state of
California, is that the building codes have gotten stricter in regard
to earthquake design but he may be grandfathered in, in regard to the
more recent building codes. He would have to check on that from the
building dept or check the code himself.
I strongly doubt that in general but since I don't know much about his
house I can neither agree or disagree as a matter of fact.
Back then, to the best of my memory, they did not distinguish the two
but I do not know now. As I recall then, it had to do more with
building materials in the construction.
As I said before, he should be able to answer his own question from
the insurance company / agent. It's possible he might get different
answers from different insurance companies too because they go by
I agree. CEA refers to California Eathquake Authority
and he specifically mentions earthquakes in the post.
In that context, clearly earthquakes are an issue. At
the very least, the answer to the question is not an
unqualifed "Yes". I would ask where the term
"bolted to the foundation" came from. It appears
he's concerned because it came from the CEA or
some insurance that references the CEA, etc. In
that case, that term and what they mean is most
certainly specified in detail somewhere and is not
hard to find.
If it's earthquake protection that is the issue, then
those bolts are NOT sufficient. On the other hand
if by bolted to the foundation they mean just regular
foundation bolts like you see all over the country
where earthquake protection is not considered
important, than yes those are typical foundation
It would appear to me that he's probably paying a higher
insurance premium because his older house is not
up to current earthquake standards. And he's
probably considering what it would take in upgrading
to not to pay the higher premium, hence he's trying
to figure out if that bolting meets the newer reqts.
I would say with about 99% certainty the answer is
no. But a bit of research online should yield the
You are correct about
the phrasing in
my home is considered "bolted to the foundation"? ..........
being qualidifed & context driven
"that term and what they mean is most
certainly specified in detail somewhere"
but you are incorrect about
"At the very least, the answer to the question is not an
unqualifed "Yes". "
It is, indeed, an unqualified "yes".
Because, I happen to know the context of the question and I see the
foundation bolts in the photos
ergo ....... his house is "bolted to the foundation".
If participants in thes thread trully deisre to become educated,
that a look at this link
Pages 14 & 15 address the OP's specific.
Page 2 is useful as well.
The pamphlet is an easy read for anyone wanting to become more
informed about hazards that older homes can have.
Also a trip to http://www.earthquakeauthority.com/CEARateForm.aspx?id=3&pid=3
and you can play around with the e/q premium calculator
You can do some "what ifs" by changing answers to what factors CEA
thinks increase or decrease risk.
Their adjustments don't seem to penalize some conditions as much I
would have thought, considering some conditions can make the
difference between minor damage & total loss. They fail to inquire as
to existence & state of cripple walls, which can be a major factor in
level of damage.
I took a look at the document you reference below. It's
vague at what constitutes acceptable bolting for an existing house
to be considered "bolted to the foundation".
I would think they would have some
clear criteria, but they don't, at least in that document. I also
looked at the "How to Strengthen Your Home Before the
Next Earthquake" document that they reference. In there
they also don't spec what the minimum bolting for an EXISTING
home is. They do say if the existing house isn't bolted
or there is insufficient bolting that to correct it you should
1/2" bolts at 6ft intervals for 1 story
5/8" at 4ft intervlas for 2-3 stories
Then they talk about drilling holes to the depth specified
by the bolt manufacturer. Suprisingly poor too, because
you would think they would spec what those bolts have
to be beyond the diameter. In reality, I'm sure that is
spec'd in the building code and I guess you'd have to
pull a permit to do the additional bolting on an existing
structure. At which point the bolts would have to be
long enough and of the correct type for the application.
Back to the original question, from what I've seen so
far, I'd have to agree with you that it appears the house
meets the definition of being bolted to the foundation.
It looks to me from the language used all they are
looking for is the basic bolting that is widely done
everywhere and that is consistent with what is in the
I'm not taking his question out of context, I am answering it within
the context that it was asked.
and the answer is Yes
from page 14
Houses that are not bolted to the foundation can
move off their foundations during earthquakes.
see pages 2, 14 & 15 (at minimum)
read the entire pamphlet if you desire to become more informed on the
Sorry Doug...... you are wrong in this situation, stop digging
The OP's question was NOT about the building code.
He asked 'does this mean my home is considered
"bolted to the foundation" ?' He mentioned the CEA.
The doc I posted the reference to is NOT a building code but it is the
relevant document to the OP's question.
Compare the wording in his question to the wording in the doc.
Re-read the OP. Go the CEA website. Take a look at the insurance
The answer to the OP's question is "Yes".
Relax, being wrong & admitting it won't kill you.
Thank goodness you are no longer designing wood framed residential
buildings..... not that is rocket science by any means.
btw the common practice when citing a code or reference is to give
section or pages ..... not just give a link.
I gave you the entire document & the relevant pages
If I gave you the relevant pages, you wouldn't understand it nor would
the OP so why bother. I gave him the answer he needs already.
And it's laughable you telling me I'm wrong when I designed per the
California code and it got approved by the local jurisdiction while
you never designed but claim that I'm wrong and you are right. Yeah
I know you have a buddy who is an engineer so that makes you
qualified. Well that aside, I appreciate a good laugh now and then.
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