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Is 4x really minimum wood post size?

Is 4x really minimum wood post size?

Is 4x really minimum wood post size?

(OP)
According to a plans review for a multi-family, 3-story wood framed apartment building structure, the "overzealous" 3rd-party plans check engineer (bless his soul) made this comment (bear in mind that the definition of "column" and "post" includes compression members located within wood stud bearing walls):

"Columns and posts souuld not be less than 4x nominal. Review and clarify. Reference IBC Section 1603.1"

Now correct me if I am wrong - what nonsense. If (2)-2x built-up post calculates adequately, I do not see anything in the "Incomprehensible" Building Code otherwise.

RE: Is 4x really minimum wood post size?

IBC 1603.1 doesn't seem to have anything to do with 4x4 posts/columns.  Its a loading section.

RE: Is 4x really minimum wood post size?

Not having my IBC handy at the moment, I can't comment on the code implication but I am inclined to believe you are correct as long as two studs are adequately fastened along its height and it calcs out.

Then again, is it such a big deal (costwise) to the owner?  If it occurs only a few times, I would bite my lips and provide a 4x post.

RE: Is 4x really minimum wood post size?

(OP)
whyun, it is a big deal in multi-family construction. If it were a custom home, a 6x6 would not cause a problem.

RE: Is 4x really minimum wood post size?

I can't find any reference in the IBC either.  Is it possibly a state or city ammendment to the code for your area?

RE: Is 4x really minimum wood post size?

(OP)
Zo40,
Negative to those. I was ranting, this plans checker did 4 pages of these nit-picking comments.

RE: Is 4x really minimum wood post size?

SacreBleu,

I'm with JAE the cited section doesn't seem to apply. Ask him to "clarify."

Rik

RE: Is 4x really minimum wood post size?

(OP)
rday,
I know it doesn't apply. That was symptomatic of his entire plans check. It is a really punitive plans check, and they (the 3rd party plans check companies) never reply to requests for clarification. Therefore, we just try our best and include an "answers to comments" letter.
Specifically, we have large metro area with various different towns making up the suburbs, all different plans check departments. They frequently farm-out the plans check to these professional plans-checking engineering consultants (some do 100% plans checking).

RE: Is 4x really minimum wood post size?

(OP)
As a postscript, we decided to register a complaint (with the Engineering Registration Board) against the 3rd party plan check company.
It would have taken more hours to comply with all the absurd comments than to do the job from scratch.

RE: Is 4x really minimum wood post size?

It is simply not possible for all building departments/agencies to handle all of the work load that are submitted by the design engineers.  Simply, there are more design engineers than plan reviewers in the world.

Thus these agencies resort to contracting out their review to various local consulting firms.

It is my experience that the expertise of these consulting firms doing plan review vary a great deal.  In addition, it is impossible for the building official to maintain consistency among all of their consulting engineers, let alone within their own departments.

From time to time, you may encounter a consulting plan reviewer who put in needless comments (as many comments as they can) as a justification of the fee they have collected from the government.

When you encounter a dispute with the "contract plan reviewer", you may contact the building official to get their official ruling.  Contract plan reviewers are not always right...

Good luck.

RE: Is 4x really minimum wood post size?

(OP)
In this case, the Building Official won't give an opinion, and the 3rd party won't answer any phone calls/E-mail. I have lost my sense of humor on this one, hence the hard line.

RE: Is 4x really minimum wood post size?

IBC 2003 sections:

602.4.1 heavy timber requires a minimum 8X6 post.

3306.7 requires a minimum 4X6 post for saftey during construction of covered walkways.

But those are the only places in the IBC that require a minimum post/column size due to detailing.

RE: Is 4x really minimum wood post size?

(OP)
VIPE-
Thanks, more back-up for my contention that this is the Ridiculous Plans Checker from Hades.

RE: Is 4x really minimum wood post size?

I agree with you SacreBlue, but I'll play Devils Advocate for a second-

The plan review company probably got the job in, and gave it to the most junior level employee to do the work, who is probably some kid just out of college who isnt well versed in the ways of construction yet.  Cut the kid a break!  We were all there at some point in time!

OK, back to normal... I had a plan reviewer make a comment one time asking if I had designed the parapets for the lateral pressure due to snow (like lateral earth pressure on a retaining wall).  Interesting comment, so I searched for any info on that subject, and found none.... If there was such a thing, then I'd imagine igloo's and snowmen wouldnt stand up.

RE: Is 4x really minimum wood post size?

(OP)
LPPE,
I didn't want to sound like I was bent on revenge. It's just that we've had too many problems from these type of "engineers", and this was the straw that broke...etc.
The developers of these large multi-family complexes are going ballistic, calling us twice a day. I believe there is some extreme economic reason they want to start the foundations tomorrow (wasn't like this 6 months ago).

RE: Is 4x really minimum wood post size?

LPPE,

In Canada a recent addition to our National Building Code was made due to the collapse of curved roof structures (quonset style building) and there is a beefy up code requirement to deal with uneven drift loading on the sides to the buildings.

RE: Is 4x really minimum wood post size?

SacreBleu:

Understand your concern.

How much money are we talking about here?

RE: Is 4x really minimum wood post size?

(OP)
smwpe,
Not sure what you mean....I meant I am aware that the bigger multi-family housing developers are nervous about increasing construction financing costs, etc. They have a lot of clout, and I am glad my boss is taking most of the heat from them. :)

RE: Is 4x really minimum wood post size?

SacreBleu,

I feel your pain. Just finished a civil job where the "administrative engineer" (his title is actually engineering technician) didn't like the linetype we used for an existing storm sewer. We ended up making a whole new linetype in AUTOCad to appease him.

I haven't seen the same type of comments coming in on structural jobs. Although, I have in the past had building departments request letters stating that some item on the plans was adequate. (You mean my seal on the plans isn't enough?)

In your response letter simply state the cited code provision does not back his assertion that a 4x post is required. I would say schedule a meeting, but you said they don't answer the phone.

I could go on and on about this kind of stuff.

Rik

RE: Is 4x really minimum wood post size?

I've got the 2003 codes but haven't really analyzed them as we still run on 2000 here.  I recall the 2000 IRC says 4x4 column min. and IBC says 6x6.

The optimist sees the glass as half full.  The pessimist sees the glass as half empty.  The engineer see the glass as too big.

RE: Is 4x really minimum wood post size?

In 1997 UBC (not IBC yet here) Table 23-II-I-1 footnote 3, it talks about using a nominal 3x member at sills and studs receiving abutting panels where forces exceeds 350 plf.  This is for seismic zones 3 and 4 only, and I'm not sure if it applies in your area.

Being in Zone 4 mostly, only time I mandatorily (?) provide a 4x minimum post is at all shear wall boundaries.  I can't recall a code section but engineers out here just do this as a standard.  For non seismic studs at doors or windows may be double 2x.

RE: Is 4x really minimum wood post size?

(OP)
whyun,
Thanks, but we don't use the California criteria here. It is very low seismic. We typically use built-up 2x for posts (that was the original plans check comment - no specific reference to end of shear wall. If load is too high, we use 4x, 6x etc.
I did a few custom homes for California years ago. I remember the requirement to use 4x posts at hold downs; (2)- 2x was not allowed.

RE: Is 4x really minimum wood post size?

Yes. 4x at all holdown posts as a minimum.

When you say built-up 2x posts, can you be specific as to what load its carrying?  In case of exterior condition double studs at openings may have gravity loads as well as wind reaction at the headers (thus 2-2x may not work at long header conditions).  I was not sure what situation warranted your checker to require 4x.

Good weekend...

RE: Is 4x really minimum wood post size?

(OP)
The exterior headers are designed with "trimmers", or "jacks" as you may call them, supporting the header 9bottom of header or beam).
The "king studs" are then run up to the double top plate of wall.
Thus, the trimmers do not carry wind load. The number of kings are calculated to carry the wind bending.

RE: Is 4x really minimum wood post size?

PSlem,

I've always preferred "The Optimist sees the glass as half full.  The Pessimist sees the glass as half empty.  The Engineer sees that the glass has a Safety Factor of two."


RE: Is 4x really minimum wood post size?

I once had a plan checker "Engineer" include this comment to my drawings. "How do you expect the load from a 6X6 steel tube column to distribute out to a 6ftx6ft footing?".
So I replied, and informed him of a new building material in common use these days,.. STEEL REINFORCING BARS!

RE: Is 4x really minimum wood post size?

One reason for spec'ing a solid post.  If you used a built up post in a shear wall, you would need to repeat your edge nailing pattern on both studs.  Otherwise one gets all the load.

The optimist sees the glass as half full.  The pessimist sees the glass as half empty.  The engineer see the glass as too big.

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