×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Another deck collapse....

Another deck collapse....

Another deck collapse....

(OP)
http://www.msn.com/en-ca/news/canada/calgary-famil...

another deck collapse.

Seems to be a trend going on. this is why i am puzzled with building code loading requirements. Our bldg code NBCC states 40 psf for single family deck loading. I disagree and think it should be 100 psf as its an assembly area.

this doesn't deter from the fact that if connections are inadequate no amount of loading will be adequately supported, nor if maintenance is neglected.

P

RE: Another deck collapse....

They almost always fail where they are supported on the house. So rather than worrying about the live load for which they should be designed, a provision requiring that all decks be supported independently of the building they serve (for gravity loads) would make a lot of structural sense. But that provision would be expected to offend the sensibilities of a lot of homeowners and architects.

RE: Another deck collapse....

IBC states 1.5 times the occupancy served...

So "residential" occupancy would be 60 psf, but "assembly" occupancy would be 150 psf.

Way too often I have seen these decks were attached through wood siding, or even brick veneer.

Heck, some of the lags either miss the studs beyond or connect to a single rim joist or layer of blocking.

Not to mention the degradation due to water intrusion issues. (I just mentioned it though, didn't I)

Rant over...

Mike McCann, PE, SE (WA, HI)


RE: Another deck collapse....

Quote (hokie66)

They almost always fail where they are supported on the house. So rather than worrying about the live load for which they should be designed, a provision requiring that all decks be supported independently of the building they serve (for gravity loads) would make a lot of structural sense. But that provision would be expected to offend the sensibilities of a lot of homeowners and architects.

Our old deck was supported by the house. The deck joists sat upon the perimeter masonry wall of the house, and were bolted to the house joists. It was far more robust than independent deck posts would have been.

RE: Another deck collapse....

Don't give code writers any bad ideas. The issue is not the loading requirements. 100psf is a massive load. It is very hard to actually get 100psf even with a packed room with people squeezed together. The main problem is that the connections are not design/built properly. It is unforgiving since there is no redundancy.

Simpson Strong Tie actually had an article on this. I believe the article was saying that deck failures are the most common structural failure. Of course they are pointing this out so that you can purchase their anchors. I like Simpson products (lots of products that helps resolve many different issues) and they work well for these kinds of conditions (but I really don't like their web page).

RE: Another deck collapse....

(OP)
I'm ok with Simpson catalogue but agree with you that their website sucks.

I also like their autocad menu to insert components into the details.

RE: Another deck collapse....

I'm about to replace my deck, I'm not sure exactly how the current one is attached. I'll make sure the new one is properly attached!

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Another deck collapse....

A few screen shots from the video in OPs link.







RE: Another deck collapse....

So by the loos of it a solid single piece deck connected to the building by two 4 inch nails every few feet.

Amazing it lasted as long as it has.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Another deck collapse....

Those nails look a bit puny; my decking nails for top boards look to be thicker than those. They also look barely long enough to get through the sheathing and certainly not enough for getting a good grip on any studs they might have been nailing to.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Another deck collapse....

Is the builder going to inspect and make good all of the substandard work that they did or will they just force the maimed to sue them? Where is the building dept. holding the builder to account? This is why the construction industry has a bad reputation.

RE: Another deck collapse....

It looks like a single ply header with about 1-inch of nail protruding. I'd say they are 10D 2-1/2" nails. Frightening indeed.

RE: Another deck collapse....

Should there be recourse against the authorities who allegedly inspected it during construction?
If the actual attachments did not meet code (and it looks like they couldn't have) then criminal prosecution of builder for fraud and/or negligence?

Jay Maechtlen
http://www.laserpubs.com/techcomm

RE: Another deck collapse....

It is hard to convince a judge or jury that someone who spends less than 5 minutes on site has substantial responsibility. Rough framing inspections by the jurisdiction are something of a formality for residential construction and are not exhaustive or continuous or in close proximity to elevated framing members. In some jurisdictions, I wonder if inspections are even based on any expertise in the trade. In Alberta there is hardly anything resembling contractor licensing or qualifications much less inspector licensing.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

White Paper - A Guide to 3D Printing Materials
When it comes to using an FDM 3D printer effectively and efficiently, choosing the right material at the right time is essential. This 3D Printing Materials Guide will help give you and your team a basic understanding of some FDM 3D printing polymers and composites, their strengths and weaknesses, and when to use them. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close