Three Decks Collapse in One Weekend

http://www.kirotv.com/mostpopular/16686572/detail.html
http://cbs3.com/local/deck.collapse.evesham.2.754419.html
http://www.wpri.com/global/story.asp?s=8540412

Looks like all 3 had the same problem, not attached to the building properly.* Now the inspectors are investigating.* A day late and a dollar short.

Now this is what I call a deck… or two!!

DSCN0391 (Small).JPG

We’re used to 6x posts and 2x10 min for decks. Looks like 4 x 4 and 2x8 at most. Course it’s a ways off.

The upper decks… I’m not accustomed to see cantalevered joist’s anymore. They still do that there? Been a few decks and apartment walkways collapse with cantalevered joists. Even a great carpenter/builder has a hard time with bullet proofing the installation in several regards there. Moisture always seems to win over time. Can’t even remember if it used to be 1 in 3 or 1 in 4 for cantalever… who knows.

Interesting pic tho, thanks.

Tim

Tim, Those are 2X10 joists with 6X6 post on 16" sonar tube with big foot plastic footings 4 feet below grade with 2 4ft pieces of rebar connecting the footings to the tube. It took 25 bags of cement for each tube/footing.

The cantilevered decks are 2X10X18 with 6 feet extending out for the balconies. This project is a 24X32 ranch that I’m adding a second floor to. I hired a structural engineer to develop the framing plan. The cost for the engineering was $4200.00, not cheap but worth it. I’ll see if I have better pictures to post.

Is that tree being used as one of the deck post? :smiley: Looks really close from the picture.

I miss New Hampsh***ah !*** Spent many a summer on lake winnisquam

Please note the common features or these, and other such stories.

  1. The deck detached from the house. Ledger board failure, not properly attached (should be threaded rods) or supported at the house side.

  2. In each case, there was a party going on. Large number of people, maybe some jumping. Exceeds the regular load factors.

  3. In our area, a while back, we had a rash of “deck collapses”. In each case, the “deck” was actually a back porch for an apartment building or condo. In each case, the porch (which is different from a deck) was over sized. Porches are for egress only and not designed, nor intended, for parties.

  4. Most of these accidents are caused by the owners not knowing these simple facts.

  • Build it right.
  • Have it designed by an SE, not just thrown together by some contractor.
  • Don’t over build it. Size it right.
  • If it is a porch, it’s a porch, not a deck.
  • Best to have all decks supported by posts to the ground and not by ledger boards.

Hope this helps;

This may help some:

http://www.awc.org/Publications/DCA/DCA6/DCA6.pdf