Deck Posts

[mthomas2]

IMO, the problem is assessing such decks in the few minutes available during a typical HI is that often they are really engineering problems, but we seldom have proof at hand that they were engineered.

The result is that such structures - though they may appear "simple" to home owners and many deck contractors - are hard to assess without the tables in hand and close attention and thought given to where the loads are going, both as designed, and if individual sections fail to to perform as expected and transfer loads elsewhere.

This deck is is a good example. To take just one detail of the design the builder decided not to incorporate a corner post extending down alongside the stringer and left us to try to decide if the result is correctly engineered.

Which, IMO, is well outside the legally defined competence of most of us.

[klott]

Originally Posted by Richard A. Hetzel

That's the general cantilever rule for joists, but it certainly does not apply to girders. Both "rim joists" on the pictured deck are not rim joists at all, but are cantilevered girders, which must be designed individually for the exact condition which will exist. There is no rule of thumb applicable here.

The girder coming in from the left appears to cantilever and carriy the load of several joists. Actually though, this may not be a cantilever at all, because the end of this girder may be carried by the cantilevered girder coming in from the right. That would make the connection between the two girders critical, and something like a top-hung joist hanger would be necessary at that corner. We can't see if there is one, so we cannot comment on it, except to raise the concern. The two girders, however, might have been designed each as cantilevers, in which case, no connection at all is required at the corner. We don't know, because we don't have any information upon which to base a judgement.

There is no limit on the length of a cantilever if it is engineered. There is no need to double a rim joist unless the rim joist is also acting as a grider, and then, it must be calculated and designed. Maybe a double will be enough; maybe it won't be enough. In the case of the pictured deck, we don't know the sizes of the girders, nor the species and grade of wood, so we do not have enough knowledge to do anything but raise a concern.

To those who continue to condemn this design without the benefit of any structural information or calculations, I suggest they make some assumptions about the size of the deck and do some calculations. They may surprise themselves, and may also fall off their high horses.

Only if the horse is on the deck!

[rwand1]

These do not appear to be cantileverd. Get off your high horse!

[Richard A. Hetzel]

Are you nuts? Do you think someone forgot the post in the corner? You don't know how the deck was designed, or even if it was designed, but it may well have been, and the design may well have been entirely competent. As a matter of fact, there is at least one cantilever, and possibly two. None of us know the answer, and none of us have the right to condemn the design without benefit of that knowledge. By all means suggest that the deck be evaluated by a licensed design professional, but there is no point in scaring the stuff out of the client with no sound structural basis, No one has the right to say that the deck is unsafe without backing up their assertion with facts. None of you have any facts.

[rwand1]

Hey I notice you are quick to come here and post, you are not a member, heck we don't even know who you are or your credentials. Only who you say you are and whose name you post under.

[Richard A. Hetzel]

...and your point is?

If you think I'm wrong and you're right, go ahead and prove it.

My point is, none of us, neither you nor I, have enough knowledge to pass judgement on the pictured deck. The best we can do is express concerns, and they should be specific concerns, and not blanket condemnations. I, for one, would seriously mistrust an inspector who dealt in general condemnations without specific information to back up his claims. I would, instead, trust an inspector who says "I have concerns about this or that, and recommend evaluation by a qualified person". One such qualified person just might be me.

[rwand1]

My point is we were asked for our comments. Thats what we provided. Apparently thats not to your liking. Thats too bad thats your problem.

You haven't proven your points any more than I have based on the photo.

I don't give a crap about your qualifications because you haven't proven anything, you can't even provide a profile.

You talk to us if we are all idiots based on your own self inflated ego.

[Christopher Currins]

This may help, Barry Adair left this on another thread.


http://buildingcodes.jocogov.org/doc...eck%20Book.pdf

[rwand1]

http://permittingservices.montgomery...ng/bc/deck.asp

[klott]

What Raymond said!

[Richard A. Hetzel]

You haven't proven your points any more than I have based on the photo.

That's exactly the point; nothing can be proven, so to make a comment such as "this deck is a disaster waiting to happen" or any of several other similar assertions is little more than blowing wind. It certainly is no help to the person who posted the pictures and asked for comments. Surely we don't expect him to relay such comments back to his client, do we? I thought the point of this forum was to help, and to discuss things rationally...and I will continue to think that and approach it in that way.

Anyone who wants to check my credentials may do so, it's easy enough.

[rwand1]

Nothing can be proven, but you shot down everyones comments but your own which you portrayed as correct.

If you are professional you would have no problems hiding behind your name only.

[Roy D. Cooke, Sr]

Originally Posted by Richard A. Hetzel

That's exactly the point; nothing can be proven, so to make a comment such as "this deck is a disaster waiting to happen" or any of several other similar assertions is little more than blowing wind. It certainly is no help to the person who posted the pictures and asked for comments. Surely we don't expect him to relay such comments back to his client, do we? I thought the point of this forum was to help, and to discuss things rationally...and I will continue to think that and approach it in that way.

Anyone who wants to check my credentials may do so, it's easy enough.

(" Surely we don't expect him to relay such comments back to his client ")
Most certainly the person asked us experienced home Inspectors for help.
If you can not see the difficulties with the deck then say nothing .
To try and come across as an expert and have this inspector take your advice and some goes wrong ( and it will for sure ) and he will be the person trying to explain why he did not report the concerns .
Remember write hard talk soft and miss nothing.
I care less about your credentials .
I saw an engineer who new zip about home inspection.
Are you a memebr of any association if not why not .
WE can all learn from each other.

A good start is here.
http://www.nachi.org/forum/showthrea...ighlight=Decks

.... Cookie

[Roy D. Cooke, Sr]

Originally Posted by Richard A. Hetzel

The best we can do is express concerns, and they should be specific concerns, and not blanket condemnations. I, for one, would seriously mistrust an inspector who dealt in general condemnations without specific information to back up his claims. I would, instead, trust an inspector who says "I have concerns about this or that, and recommend evaluation by a qualified person".[COLOR=red

One such qualified person just might be me[/COLOR].

( " One such qualified person just might be me ")
I sure hope you are having a bad day your post looks to me like you are trying to generate work.
People pay me good money to make decisions and I do .
I am not saying that I never recommend further but in most cases I tell it like it is,and this one needs Immediate repair or replacement.
....... Cookie
.

[Kenton H. Shepard, CMI]

Originally Posted by Richard A. Hetzel

...To those who continue to condemn this design without the benefit of any structural information or calculations, I suggest they make some assumptions about the size of the deck and do some calculations. They may surprise themselves, and may also fall off their high horses.

I appreciate your technical analysis Richard, few of us here have the background to do the calculations you mention, although a number of us have practical expertise. It's the combination of the two that really makes for informative posts.

Thanks for taking the time to add your perspective to these boards.