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July 22, 2003 The city has done 1

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dik

Structural
Apr 13, 2001
25,841
July 22, 2003

The city has done a vigorous job of going after Philip Pappas, the owner of the building whose porch gave way on June 29, killing 13 young people and injuring more than 50.

The North Side landlord has been cited for alleged violations at the Wrightwood Avenue apartment building. He also faces charges in connection with a host of alleged infractions at more than three dozen other properties he controls that were inspected after the accident. Appropriately, the courts will decide Pappas'
culpability.

But the administration of Mayor Richard Daley must face the fact that the city has sent mixed messages about porches and their proper use.

On the day of the accident, Buildings Commissioner Norma Reyes said that porches were meant for entering and leaving apartments--not for parties. But only a few weeks earlier, she issued a press release reminding property owners to inspect their porches before entertaining. The release added that use of gas grills on wooden structures represented a fire hazard and advised people to exercise caution.

After the accident, officials said that if the porch that collapsed had been built to specifications spelled out in the city code, it safely could have held 12 people. The figure appeared low, since the code sets a standard of 100 pounds per square foot and a legal structure containing a maximum of 150 square feet could have handled 15,000 pounds.

Nevertheless, even the 12-person total implies use for entertainment.

Some Chicagoans live in three-flats and six-flats whose back porches and landings are so small that the idea of throwing a party would never cross their minds. But city officials certainly must know that landlords in neighborhoods
that attract young renters use big porches as a marketing tool.

Daley has said his administration is willing to look at code revisions as it seeks ways to prevent a disaster similar to the one on June 29.

But as they ponder options, they should consider amending the code to create two permit categories: porch, whose maximum size is small enough to discourage social categories; and elevated deck, with appropriately higher construction standards that assume use for entertaining.

And, as with elevators, officials should think about a requirement to post capacity limits. That way, tenants and visitors alike would have the ability to look at the placard, count noses and make personal safety choices.

Once good code revisions are in place dealing with new construction, Daley must grapple with sensible ways to ensure the safety of the thousands of existing porches throughout Chicago.

Separately, the mayor and his aides have to face the reality that some people--correctly or not--believe that getting a building permit for a porch is a time-consuming and frustrating experience. The city contends Pappas failed to
obtain a permit for the porch that collapsed and allowed it to be built in a substandard manner. Obtaining a permit ensures that plans will be checked for code compliance and that the finished product will be inspected.

Landlords must be assured they will not suffer for doing it the right way.

Copyright (c) 2003, Chicago Tribune
 
This fall I will be teaching a continuing education college course to prepare EIT's to take the Civil Engineering (Structural) PE exam on October 24. Am considering looking at the engineering details of this disaster as part of the review of failure analysis. Can anyone give me a link to information on the details of the porch design?

Thank You
 
This information may be available from the City of Chicago... they scooped all the evidence before anyone had an opportunity to examine it and for 'safety' reasons demolished the landings. I understand that their records consists of photographs only. With the pending litigation, I'd be surprised if they readily release it or if the information is complete.

With litigation stuff that I'm involved with, I usually permit the 'other' interested parties access to the failure as well as allow them to remedy the problem, if applicable.
 
I don't understand why the City of Chicago says these facilities should be designed to 100 psf, unless they have a special provision in their building code I'm not familiar with. Table 16-A in the 1997 UBC says Exit Facilities serving an occupant load of more than 10 people need to be designed for 100 psf. However, it seems that this would follow residential loads which would be much smaller, either 60 psf or 40 psf, depending if it is considered a deck or a balcony.
At 40 psf the total design load is 6000 lb. or 35 pretty large people. With any factor of safety, the load could be much higher. I suspect that either the detailing or the members couldn't take even these loads.
I think the City is taking an overly defensive approach by exaggerating the allowable loads. There's probably a detail, such as the joist/ledger connection that wasn't constructed to any kind of engineering requirements. Once this failed, the effect cascaded, causing the collapse and deaths.
 
Sorry to hear about the passing of your namesake... remember him as Georgie Russel...

It's not uncommon for balconies to be designed for 100 psf LL. For residential outside of houses and small buildings, the Ontario Building Code stipulates 100 psf LL.
 
to dik,
You should look at the Ont Building Code again. It says exterior balconies under part 4 and interior balconies subject to assembly shall be designed for 100 psf and interior balconies other than assembly refers you to note 1 which allows you to design to the room occupancy if there is no assembly. Then if the building comes under part 9, you can use that to justify the lesser loading. I get involved with a lot of townhouses and it becomes a judgement call, but generally 40 psf will suffice, unless you get a special case i.e. a townhouse facing a major attraction(park, major street,university) with a large deck.
Gary
 
Correct... I was only pointing out to Jed that 100 psf is not unusual... sorry for any confusion...
 
Gary... just revisited the OBC regarding balcony loadings...
Under 4.1.6.3, using Table 4.1.6.3...

for residential(falling under Part 4), the loadings are:
sleeping and living quarters in apartments... 1.9(40)
work areas within... 2.4(50) and there is no provision for balconies, except under the Balcony heading of Table 4.1.6.3.

Balconies are covered under 'Balconies'...,
Exterior... 4.8(100)...
Interior and Mezzanines that could be used for the assembly of people as a viewing area... 4.8(100)
Interior and mezzanines other than above... (3)(see 4.1.6.4)

4.1.6.4 notes: The following shall be designed to carry not less than the specified load required for the occupancy they serve... c) interior balconies and mezzanines...

The key word is interior... Residential exterior balconies other than those for houses and small buildings(Part 9) require 100 psf LL as noted in my earlier post. That it was an exterior condition, was implicit; the Chicago balconies were exterior...

 
Thank you for all your responses. My point was that the balcony (or porch or deck) couldn't take 100 psf and I doubt it could take 40 psf. There was some flaw in the design and/or construction that caused the more heavily loaded top floor to fail and land on the stairs and porches below.
In addition, my suspicion is that no engineering was done on this structure. Some contractor put it together using somewhat marginal techniques that he had used in the past (maybe for a smaller deck or a shorter span)and it caused the failure and deaths of 13 people.
 
Anouther case where the codes may be adaquate (I use 50 psf in my designs), but buiding techniques and inspection were lacking.

Is the Ontario Building Code code body for Chicago?
 
Boo1... agreed, else there wouldn't have been a collapse or maybe something on the building itself that the deck was secured to...

OBC has no jurisdiction in Chicago... only used to point out that some codes require a loading different than 40 or 50...
As noted in a different thread... the 100 psf loading represents a 200lb person on a 1'5" grid... (stipulated loading includes some component for dynamics, too, I suspect). I guess if the code stipulates 100psf, I'd be reluctant to use otherwise...

I'm not sure who came out with the 12 person maximum (condition of Chicago, perhaps). I did up a report for a deck collapse a couple of years ago... a bunch of international people were injured when it collapsed during a party... No vertical supports, diagonal only strut/column from the outside edge of the deck to the foundation wall of the home. Horizontal component pulled the deck away from the home... as the deck attachment failed, there was less to secure the deck and the horizontal component increased... The deck had not been loaded to this extent before and there were some traces of dry-rot...
 
Chicago, I believe, has their own separate building code, aptly named the "Chicago Building Code". I think it is an offshoot of the BOCA code, but not sure.

I think we have a copy of it around here somewhere and I'll see what it says about deck LL.
 
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