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Weak Deck

In a house I just bought, I was having 3/4" hardwood installed. They staged at least 2,000lb of material on the rear deck. The deck was enclosed underneath with more stone veneer so I couldn't see the conditions of support. I commented I was worried about the load, the workers said "it will be fine" and jumped up and down and "see, it's solid". I got the load moved pretty quickly. Fast forward 3 weeks, I finally got the wall under the deck open. Glad I moved the load. Improper ledger attachment, actually can't see the connections, on the surface of brick veneer with no intermediate column support, improper joist support, concentrated load from double joists supporting an exterior stone veneer fireplace surround. And those are just the problems with the gravity load. Frankly surprised it survived. Deck repair/replacement on the horizon!

Rant...a little of topic but....
The fireplace is a wood burning unit, on a framed in and covered wood deck and roof. No hearth extension unless you count the 5/4 decking. I had a company come out to see about converting it to gas logs. In our conversation I asked if they would secure the permit. They said they didn't need a permit. I asked him if he knew why whoever did this thought it was a good idea to put a wood burning fireplace on a combustible floor with no hearth extension over a completely enclosed crawlspace blocking several house foundation vents on a deck that violates almost every prescriptive code in the book.. He said no. I said it was because they weren't required to get effing permits.
 
Reason #267 why Canadian decks require 6x6 posts. We got this white crap that falls from the sky and hangs around for a while.... and that white crap can get kinda heavy, esp. if it rains a bit ....
 
Reason #267 why Canadian decks require 6x6 posts. We got this white crap that falls from the sky and hangs around for a while.... and that white crap can get kinda heavy, esp. if it rains a bit ....
I've never seen a deck collapse because the columns were too slender and buckled. They always fail at the ledger or connections.
 
I've never seen a deck collapse because the columns were too slender and buckled. They always fail at the ledger or connections.
The 6x6 requirement in Canadian codes come from issues with 4x4 not being able to resist the necessary lateral loads in every wind zone in Canada. 4x4s can only be used where calculations show them to be acceptable.
 
Nothing is "always" and when you live in high wind areas, the deck to house connection is just as important as uplift.
The original statement is a good example of a hasty generalization logical fallacy, as the sample the analysis is taken from (their experience) is not adequate to come to the conclusion that it could not be an issue.
 
The 6x6 requirement in Canadian codes come from issues with 4x4 not being able to resist the necessary lateral loads in every wind zone in Canada. 4x4s can only be used where calculations show them to be acceptable.
How are the posts loaded with wind? I've also never seen a moment connection on a deck post.
 
It has nothing to do with the size of the posts and everything to do with the connection of the posts at the base and the deck framing.
That's a connection. I'm confused. My post was saying I've never seen a deck fail because a 4x4 post buckled and specifically said they fail at connections. How does a 6x6 solve this uplift connection problem?
 
The original statement is a good example of a hasty generalization logical fallacy, as the sample the analysis is taken from (their experience) is not adequate to come to the conclusion that it could not be an issue.
Providing ones professional experience is not a logical fallacy. The post literally started with "I've never seen" to qualify it as my experience. I'm also questioning it as a structural engineer because it is difficult to design a deck where the posts would overload a 4x4. They would have to be very tall.
 
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