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Re: Wood Grading Stamp

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Jordan,

My one comment would be to be careful with the terms lumber and timber.
Two completely different animals.

Our timbers that we get from the mills/lumberyards (stil get timbers from
"lumberyards" <grin>) are generally not stamped as the stamp will mean
nothing in our case (as we will be cutting many members).  We still will
order material to No2, No1 or Select Struct and that is what they will
ship, but then if say a Select Struct piece as grade at the mill is to be
cut, it must be re-graded (which we will unofficially do at a minimum and
officially do if required) to verify that the cut member will still be
Select Struct is that is what is required.

As to "rustic", I believe most people would consider a timber frame home
to have a "rustic" feel (although it is depending on other aspects too),
yet most timber frames use planed members.  We do have projects that call
for rough sawn look or even something with an intentially "distressed" or
weathered/worn look.

I hear you on the what is feasible/achievable.  We generally use No 2 Oak
(White or Red) or DougFir.  Going to Select Struct or even No 1 is only
done when needed and even then it is costly and sometimes not feasible
(getting cross sections with dimensions of 16" or more in long lengths of
Select Struct Oak is really tough and very expensive...a little easier in
DougFir).

It is also fun to read some specs on projects created by architects and
engineers.  Many use "boiler plate" specs that are really gears to things
like glulam, etc.  Such specs usually call for wood to be supplied with a
moisture content of less than 19% (i.e. non-green lumber/timber).  While
this can technical be done by kiln drying timber members, they will more
than likely just collect moisture again in the time it takes to fabricate
and ship to the site.  We generally deal in green timber (i.e. moisutre
content greater than 19%).  It is also fun to see the specs that call for
all the timbers to be Select Struct even though there is absolutely no
need for it...just added expense to the project for no reason.

So, I will agree than contractors can be crafty and look for ways to get
around stuff, but that is not always the case.  And I will offer that
there are significant number of engineers and architects that specify
stuff that is plain wrong or just not needed.  So, remember it goes both
ways.

Regards,

Scott
Adrian, MI


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

> 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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