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#163434 - 05/08/07 02:02 AM House collapse!  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
This afternoon my wife says, "Did you hear about that house that fell over on the other side of the neighborhood?" - "No way - lets go see..." Anyway I took some pic's. And I see no evidence of cribbing or steel in the wreckage, only the guy who did it will know for sure what happened. What is obvious is what did not happen.

Now before I go any further I should mention that there is a moritorium on demolition permits in SF, and this building is worth more (much more) with the house in this state, than it was before or during construction. It is no secret (because they are very rare) that empty lots in SF can START at $700K - next to a park this lot will ask about $1M to start after the back-hoe gets done! If it were not for endangering himself, family and dog - as well as a few fire fighters - he may have just made a half million by letting his house fall. (less the damage to the house next door which does not seem to be very severe.)

Anyway, I saw some things that I thought were odd that you all might get a kick out of.
[Linked Image]
House pulled away from the service - now theres a first!

[Linked Image]
I would have never thought to use the the red tag to advertise! Yes, GC's are sticking there biz cards all over down there, as people - like myself - are down there gawking, and taking picks and have construction jobs on their minds. Only this guy (who lives up the street) stuck his to the red tag, the rest are all over the police barrier.

[Linked Image]
This is what you get for over .5M$$$ In the paper last year as the "Cheapest House In SF" - You get to call a back-hoe.

The most worrisome part about this is that this guy would have never won the bid for this "home" had there not been a morritorium on demo permits due to anti-developement and rental policies that dont allow you to tear down any habitable space. This building would have never come down had it not fallen - but should have been bull-dozed years ago. IMO.

More...
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/05/07/COLLAPSE.TMP



Mark Heller
"Well - I oughta....." -Jackie Gleason

Work Gear for Electricians and the Trades

#163477 - 05/08/07 08:28 PM Re: House collapse! [Re: e57]  
SolarPowered  Offline
Member
Joined: Jul 2004
Posts: 625
Palo Alto, CA, USA
Mark,

What, exactly, broke to cause this collapse?


#163487 - 05/08/07 11:34 PM Re: House collapse! [Re: SolarPowered]  
ShockMe77  Offline
Member
Joined: Jun 2005
Posts: 821
Rahway, New Jersey
Great shots Mark!

My guess would be that A foundation wall had some previous earthquake damage and some "contractor" came along and disturbed it enough to break it. Either that or the HO decided that he had enough and finally got rid of that pole in the basement!


#163493 - 05/09/07 01:34 AM Re: House collapse! [Re: ShockMe77]  
stamcon  Offline
Member
Joined: Mar 2001
Posts: 329
So San Francisco CA
The homeowner was in the process of replacing the foundation.
According to the deputy director of inspection services in the city's Department of Building Inspection, "All indications are that the building was inadequately shored and braced for that work and that the shoring gave way."
Hmmm...if the shoring gave way...I don't think it was properly braced.
steve


#163500 - 05/09/07 03:44 AM Re: House collapse! [Re: stamcon]  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Normaly - around here, not sure if it done in a simular way everywhere - the standard practice is to knock several holes in the front and back of the house, then bring in temp steel beams (10X8" or >), then use 6X6"X5' cribbing in a square (stable) configuration, and not even lift the house. (As like in this case there is zero property line clearance and often homes are surface to surface with each other. This one only has an adjacent home on one side, an open park on the other.) It is an extremly stable method and one of common practice. I saw no evidence of this what-so-ever.

Most of these homes have a wooden beam that runs down the middle under one of the bearing walls to the roof. Usually a hall or other partition in the middle. And ing the lower area under the house it is braced with either 45 degree placed lumber as a gusset, or dependant on the sheathing to act as a primitave shear wall. From the appearance of the back, and the way it swung out, away from the other house into the park suggests he may have removed sheathing from the lower rear of the house eliminating what little shear value it had, all the rest of the damage is from the lower area of the house folding like a house of cards.
http://www.sfgate.com/cgi-bin/object/article?f=/c/a/2007/05/07/COLLAPSE.TMP&o=2
FYI there was a whole stack of OSB that has the least amount of shear value to any plywood, and that no one in their right mind (if they knew anything) would use for any structural repair. See pic #6 in this slideshow.
http://www.nbc11.com/slideshow/news/13269746/detail.html

He may have also just knocked the foundation out, and relyed on the posts that hold the main beam up to support the house.

Or.... the house was so bad that the house just gave way, not the shoring.... It was apparently that bad off to begin with...



Mark Heller
"Well - I oughta....." -Jackie Gleason

#163504 - 05/09/07 06:35 AM Re: House collapse! [Re: e57]  
pauluk  Offline
Member
Joined: Aug 2001
Posts: 7,520
Norfolk, England
Quote
empty lots in SF can START at $700K


Yikes! shocked


#163514 - 05/09/07 11:19 AM Re: House collapse! [Re: pauluk]  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Highly competitive bidding amongst developers, as you can either plop down 3-4 condo units @ $650k+ depending on location etc, or 1 $1.5M single family.

The only reason that house went for what it did last year is because it would have been like pulling teeth to tear it down, as it should have in the first place. otherwise that nieghborhood goes for $8-900K, > if in great condition or good location.

Last edited by e57; 05/09/07 11:30 AM.

Mark Heller
"Well - I oughta....." -Jackie Gleason

#163643 - 05/13/07 01:08 PM Re: House collapse! [Re: e57]  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Same place one week and several trips to the dump later. (Nice view of San Bruno in the backround.)
[Linked Image]


Mark Heller
"Well - I oughta....." -Jackie Gleason

#163650 - 05/13/07 03:07 PM Re: House collapse! [Re: e57]  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Permit and complaint search on this property notes state that a complaint was filed 2 months prior for exceeding scope of work to remove & replace sheathing in the rear, and right of the home. "Foundation tearing" A permit was issued for the foundation work to comply with the violation notice. Maybe it should not have been issued to the "home owner"...


Mark Heller
"Well - I oughta....." -Jackie Gleason

#163654 - 05/13/07 06:28 PM Re: House collapse! [Re: e57]  
togol  Offline
Member
Joined: Sep 2005
Posts: 421
NW In. USA
so the guy accidently demolishes a shabby house and now stands to reap the $$$$$ from the sale of a vacant lot ???


Tom

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