Yet Another Deck Collapse Injures Four People

[hausdok]

You'd think that after more than 15 deck collapses that injured people in 2005, officials in every city around the country would be automatically inspecting every deck within their city limits.

Not so - at least in Lawrenceville, Georgia, where a second-story deck collapsed as the house, which is a foreclosure that's up for sale, was being shown.

To read the entire Atlanta Journal Constitution, click here.

[Bain]

I'm a freak about decks being properly configured. The deck in the photo's gonna fail at some point if it isn't repaired. Check out the homeowner's prop against the far left pier, and how the second pier from the left has deflected out of position. The far right rim joists--which aren't visible--had separated nearly an inch due to the pier beneath it moving outward. I had buyers walk away from this house last week, and wondered if I should have sent the sellers a certified letter telling them not to use the deck until it was modified.

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[Mike Lamb]

For the HI, looking at how the ledger is anchored to the building is what's critical. This seems to me to be the common thread to the lethal vanishing floor tragedies we've seen. Ledger failure. The house is not supporting one side of the deck. The fasteners are.

I think solid anchoring every 16" or two anchors every 32" are now required in Chgo. The outside columns and rim joists are important but fail more slowly.

From the AJ-C article, Mr. Bill Hope, whoever he is, seems to agree.

DECK WARNING SIGNS

Bill Hope, a certified home inspector, lists these scenarios:

> Bolts connecting the deck to the house aren't connected to a solid piece of wood. "A lot of times when a deck fails, it's not the posts. It's the attachment to the house."

2 years later and that Chgo. horror is still sickening.

http://www.cbsnews.com/stories/2003/12/ ... 8736.shtml

[Bob White]

Here's the link to the local news video on that deck collapse:

http://www.11alive.com/video/player.aspx?aid=57642&bw=

Looks as if the deck was nailed thru hardboard siding, no flashing.

[Brian G]

I cringe when I think of how many decks around here are built just like that. It's one of those things many people assume almost anyone can build...but not properly. It's sad in a way, but I hardly ever get any grief about writing up crummy deck construction anymore because of all these stories. I tell doubting clients or sellers to just Goggle "deck collapse" and see what comes up.

Brian G.

Decks Aren't Deckorative Items []

[Terence McCann]

A book I recommend reading is:

Manual for the Inspection of Residential Wood Decks and Balconies. It was published by the Forest Products Society and the ICC.

It can be purchased here http://www.iccsafe.org/e/prodshow.html? ... iapCga4748

One of those books all HI should have.

[FrankWoeste]

We have a new publication that adds to what is in the deck inspection manual. A summary of the five (new) papers follows. You can order it by going to the attached file. If you want a copy of a paper with my name on it, please e-mail me and I'll send a copy.

Thanks, Frank Woeste

e-mail:fwoeste@vt.edu

Wood Design Focus Editorial

This issue of Wood Design Focus deals with deck design and construction. One only needs to do a web search on “deck collapseâ€

[carle3]

Good timing on this article. I just got done with a 2 family yesterday that had a 2 story balcony. I found 4x4's wrapped in aluminum supporting this structure. I found some rotting wood in an exposed area. When you grabbed the 4x4 and shook it the dry rotting material would come falling out of the aluminum seams. Looking at what this thing was sitting on I found the 4x4's hardly bearing on a couple concrete blocks laying on grade. I went home feeling pretty good figuring I just saved someone's life, although they probably do not will not realize this as the realtor will tell my client that I am being over dramatic.

[Brandon Chew]

Regarding the deck in Bain's picture: Has the back of the house decided yet if it wants to join the deck on its journey down the hill? With that large overhang at the eaves, I also wonder how much of the roof load is supported by those posts and how much is cantilevered back to the wall of the house.

Thanks for the links to the deck resources.

Brandon

[MelB]

So they were in the middle of their inspection when the deck collapsed? I wonder if he had already seen the deck issue, mentioned it, and the realtor took them out to the deck to jump on it, and prove the inspector was just being overly dramatic...

[Chad Fabry]

Hey Mike,

Thanks for the topic and the links. I mean that.

I've been waiting for days for the "editor" to fix the the topic headline. How do I find that guy?

[hausdok]

Fixed. Thanks. Semetimes the mind sees it but it doesn't register.

OT - OF!!!

M.

[paul burrell]

Did a new home today. The deck was well built with anchor bolts and joist hangers. The bolts were installed in I Joist webbing which was used for band sills on house. Seems like a sistered 2x6 inside to hold bolts would be better than only OSB webing. Did not look secure in the long run to me. Flashing was also installed.

Whadda ya think,

PWB

[Brian G]

I'm with you Paul. Bolts held only by OSB? Better than nothing, but not that reliable (IMHO). How big was the deck?

Brian G.

Where's the Beef? [:-magnify

[hausdok]

Hi,

I just got off the phone from talking to Ray Clark at the APA Help Desk. He said that they would not recommend that application because it would place unacceptable forces on the web of those I joists. Just on the off chance that they might have something not on their site, he then searched his database to see if he had anything. He doesn't.

Other than their detail for attaching a deck to an APA-rated rimboard, which isn't anywhere near as weak as attaching to an I-joist, they haven't published anything because they don't recommend it. His take - add posts under that ledger to support the load and then anchor the posts to the sills to prevent it from pulling away from the structure.

Here's the link to APA's manual.

You'll have to register at their site to get it, but it's free and they do not spam you. Once there, you've got access to tons of really good information.

ONE TEAM - ONE FIGHT!!!

Mike

[paul burrell]

Originally posted by hausdok

Hi,

His take - add posts under that ledger to support the load and then anchor the posts to the sills to prevent it from pulling away from the structure.

Makes sense, add posts. This Company builds hundreds and hundreds of homes in this area yearly. And is known for this type building practices. Shoddy. If I write this up he will say show me the code section. All I can tell him there is no code for shoddy building practices.

PWB

[paul burrell]

Originally posted by Brian G.

I'm with you Paul. Bolts held only by OSB? Better than nothing, but not that reliable (IMHO). How big was the deck?

Brian G.

Where's the Beef? [:-magnify

Not very big maybe 10'x 20'

PWB

[Danny Pritchard]

I looked at this deck a couple of weeks ago.

The first picture is of the end unit of a condo complex.The 2nd and 3rd pictures show the balcony joists below the baywindow attached to a ledger that is connected to the I joists of the house using joist hangers.These hangers have been installed upside down and secured to the ledger with 2 nails.

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[hausdok]

Okay,

Well, being in Georgia and with what's happened right there in Lawrenceville (the lead on this thread), he'll be more cooperative.

Here're a couple of other sources. The first is an article that we'd previously run here on TIJ written by Frank E. Woeste Ph.D., P.E., and Joseph R. Loferski, Ph.D. that discusses deck connections to houses. The second is the permit and construction guidelines for decks under the 2003 IRC. The third is from the Gwinnet County website.

Click here for the Woeste/Loferski article. (Check out example 2.3b)

Click here for the IRC document.

Click here for the Gwinnet Country site details.

Lastly, I spoke to Bill Grove, President of the Wood I-Joist Manufacturer's Association (WIJMA), by phone about 30 minutes ago. Grove disagrees somewhat with Clark and says that it really depends what the manufacturer of those I-joists specifies, but, if one were to back up the siding and sheathing with a stiffener between the webbing of the I-joist and the sheathing, that it should work just fine. That detail is detail 1f of the APA I-Joist manual and can be found at the bottom of page 4.

ONE TEAM - ONE FIGHT!!!

Mike

[hausdok]

Hi Danny,

Uh, Uh. Besides the idiocy of using the hangers upside down, there aren't any stiffeners between those doubled up joists (See Figure 5a-Alternate Method 2 on page 10 of the APA manual at the link in my previous post.

ONE TEAM - ONE FIGHT!!!

Mike

[Bain]

And how are the doubled up joists connected to one another? Let's have a party with lots of bodies in the breakfast-nook bay window and on the deck and see what happens.

[Brian G]

Originally posted by paul burrell

Not very big maybe 10'x 20'

I asked because I always tell clients to envision how many people would fit on a given deck if there were a party or family event. That's normally when the tragedies happen. They seem to get it from that most of the time, but occasionally I get a guy who just shrugs it off and says it'll only be the few of them. One can only try.

Good catch on the OSB, by the way. Is this a fun job or what? [:-angel]

Brian G.

Who Can Save an Idiot From Himself? [:-dunce]

[emalernee]

Mike,

The upside down hangers are installed that way because the rim joist is hanging from the ends of the I-joists. Seeing as the I-joist are doubled up at the overhang, is means that the joist were not long enough for the bay window. Hows long the extended I-joist are and how they are attached to their sistered joist plus the missing blocking at the I-joist to rim board is the question.

That question should be answered by a PE and documented to the AHJ. As it is now, looks like something hacked together by a underpaid and under educated carpenter. Get the AHJ involved and save the world. If they won't help, there is always the Press.

Ezra Malernee

Canton, Ohio