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Re: Wood Grading Stamp

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Scott,

I'll agree that there may be more than meets the eye.  "Rustic" to me usually means rough-sawn. Often, I will be asked to evaluate structures which have been sawn locally from local stands and have never been looked at by a grader.  Based on my dealings with contractors, I made a few assumptions to fill in the blanks: If the lumber had been ordered to the spec, there will be a paper trail. If there were a paper trail, i.e.: the contractor knew about  the spec and followed it, he would have produced it.  You may have gotten the impression from our IRC table discussion that I think residential builders are stupid. Quite the contrary, they're a crafty bunch, and they know how to work the system if it will help their bottom line. They call it "efficiency."

So, I've guessed that these are rough sawn timbers which were ordered without the benefit of species or grade requirements.  I didn't mention in my original email that you must be careful to make sure you haven't specified the impossible/impractical (started to, and decided to delete it).  For example, it is typically not allowable for lumber to be graded without stamping, and stamping generally is only available in production mills (excuse the inaccuracies there, I don't remember the proper language...suffice it to say that you won't get a stamp on 2x lumber from a grader visiting a mom-and-pop mill).  It's quite embarrassing to specify an impossible requirement (re-tempering an AL weldment made from H-series "tempers" comes to mind), and you do need to be careful not to allow a crack in your armor when dealing with a belligerent contractor.

Still, if the certs can't be found - or, as I suspect, don't exist, they need to be re-created. If the material is weaker, it needs to be re-analyzed. If it doesn't work, it'll need to be replaced.  I've heard this argument from contractors too many times to be fooled.

Now, if you'll excuse me, I need to go figure out how to fix a tall wall that a builder friend managed to construct from Lithuanian Norway Spruce instead of S. Pine. (I wouldn't' be surprised if it isn't a choice wood for beginning wood carvers, as soft as it is). I'm just glad I had the idea to snap a pic of the grade stamp before I left the site, or I might have never found it in the book.


Scott Maxwell wrote:
I think Jordan's response is right on point...to a degree.

In general, timbers used in timber framing will _NOT_ have grading stamps
on them for many reasons.  One such reason is for appearance reasons
(timbers, especially in timber frames, are generally left exposed and a
grade stamp is not exactly a visiable pleasing thing).  If proof of
grading is required, it is generally done by way of a letter from the
trained/certified "grader".

Thus, in my opinion the arguement has merit but also is bullsh!t to quote
Jordan.  It all depends on how one looks at it.  If the arguement really
is meant to be something like "we don't put grade stamps on timbers for
aesethic reasons, but can provide proof in other manners", then it is 100%
correct.  If on the otherhand, the arguement is that "we are not providing
a grade stamp cause we don't want to and you will just have to believe
us", then they should be called on it.  So, I would suggest that a little
more information is warranted.

I would point out that some would consider the spec requirement to be too
restrictive and "bullsh!t".  Why do you need to have a grade stamp when a
letter will work, especially considering that timbers generally have a
real aesethic component.  It could be that it is a case of an engineer not
being familiar with the "standard of practice" of a particular trade.

So, I would relax a little and find out if the contractor is taking a
literal reading of the spec and does not want to provide an actual stamp
on the wood, but would provide a letter from a certified grader.  If they
resist providing such a letter at least, then something starts to smell in
my opinion at that point.

Regards,

Scott (who happens to work part-time for a timber framer)
Adrian, MI

On Thu, 8 Sep 2005, Jordan Truesdell, PE wrote:

  
That argument is, excuse my language, bullsh!t. I wouldn't sign off on it
unless the timbers were massively overdesigned and I knew that I could
make the job work with absolutely lousy wood. 

The best thing to do is to make him get the timbers graded and accept a
letter of grading from a properly trained expert.  Let him know that if
the grade is weaker, he'll have to pay for a re-analysis and may still
need to get stronger timbers based on your new analysis and the timeber
grade he has.

joraljim(--nospam--at)prtc.net wrote:

      I designed a small wood dock structure supported on 8"x8"
      timber elements. In the contract documents, I specified that
      the each piece of lumber shall have a grade stamp of grading
      agency.

      The contractor provides timber elements without any stamp,
      arguing that the timber are "rustic" elements.

      Is that argument acceptable?

      Jorge Jimenez, EIT



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