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RE: anchor bolts/ deck collapse

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As an ex-Chicagoan I know this area very well. It is far from a slum
area - in fact, it is located very close to Cubs Park - an area that is
noted for a massive regentrification program that started some twenty
years ago. This is an upscale building comprised of mostly Unreinforced
Masonry Buildings with rear-wood Egress. In the early 1900's, before air
conditioning, the families that live here slept out on these decks on
hot nights. Milk was delivered every morning on these decks and it was
not uncommon to find lawn chairs set up on the deck so at night
neighbors could rest and share stories of life.

This particular building was remodeled. It was converted from six
apartments to three - increasing the size of the units. If the units
were rented - it was not done so as by slum lords and the number of
occupants were probably high to share the cost of the rent. This area is
close enough (by Elevated Train) to be near DePaul University,
University of Illinois Chicago Circle Campus, Loyola University,
Roosevelt University and a few others I probably forgot. 

In other words, it was an upscale neighborhood seeking high rents. I
would suspect that the deck might have been original as there was one
stair normally leading to each level from the back. If it was added, it
would have been a bolted ledger and this may be the problem. However,
you can't disregard that the failure might have also occurred at the
wood to wood connection at the front of the deck (farthest away from the
brick wall.

There were plenty of photos of the Inspectors who were looking at the
damage. If there was a live load restriction on the deck, it was
overloaded. A neighbor noted that there was a party going on and at
times she could see more than 100 people on the deck, standing on the
deck, stairs and landings drinking and generally having a good time. It
wasn't, in my opinion, an intentional or defect that caused the collapse
and their would be no reason to assume that the removal of the materials
was an intentional cover-up. If it were, it would have to have been the
contractor or building owner who initiated the removal of the materials,
and the City would not allow this until the investigations had been
sufficiently complete. I suspect that they did not wish to leave the
remnants of such a horrible "accident" from the neighborhood.

I tend to think it was a simple, but horrible accident. The number of
persons on the deck exceeded either the ledger connection or the
connection (beam, flush beam etc?) at the front of the deck live load
(considerably) and the deck collapsed. 

My opinions are formed from what I could see of the ledger, the wood
joists at the ledger and front of the deck which was published on the
Chicago Tribune website (you need to subscribe online - this is free -
to have access to the photos and video links). I've known Chicago police
in this area (now retired) the changes that have occurred in Lincoln
Park (my brother lives very close to this area off of Lake Shore Drive
and Addison) as well as the area near where my parents were born and my
grandparents lived. 

On final thought: If there was a failure caused by negligence, the
likelihood is that metal connectors may have been installed incorrectly.
Metal connectors have changed a tremendous change for the good in wood
construction - however, most all of us know or have seen how the
installation of metal connectors have been used creatively by framers
who do not understand that they may be weakening the structure. Time
will tell us most of this as I would expect the wood from the deck has
not been scraped but taken to another site for inspection and


-----Original Message-----
From: Gerard Madden, SE [mailto:gmse(--nospam--at)] 
Sent: Tuesday, July 01, 2003 10:21 AM
To: seaint(--nospam--at)
Subject: RE: anchor bolts/ deck collapse

My first thought was dry rot of the joists or ledger because it looked
like the exterior posts were still there after the collapse. Then I saw
it was 3 stories high and this would be 100 psf live load for exiting in
California. Then I heard this thing was relatively new and then I
thought poor construction or unpermitted work/repairs.

Believe me, if these were college students, they have a slum lord as a
land lord, probably went with the cheapest guy he could find who cut
corners where ever possible on the construction. What's the standard in
Illinois for plan checking and inspection???

I also wouldn't rule out the students doing something wrong. I lived in
a house in college where the half basement was dug out so an extra room
and a place to drink/have parties could exist. I remember one day in
class our professor was telling us a story about how some local clowns
did exactly what I just described and how the place would never survive
an earthquake. He named the house and me and my roommate stated to the
class "We live there, in the basement too ! " ... Other than some lost
brain cells, we made it... but college kids are crazy when alcohol is
around. I wouldn't be surprised if they stacked kegs on the deck or
jumped in unison causing overloading or vibrations.

But I wouldn't rule out mistakes on the engineers part. I've seen some
stupid shit in my few years in the business on very simple structures.

Santa Clara, CA

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