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Re: 3x_ versus (2)-2x_

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For information, the Oregon Structural Speciality Code (97 UBC with Oregon
State Ammedments) went out of the way to delete this 3x requirement for
sill plates over 350 plf.  Why?   Washington State, Oregon, and California
editions of the code are have slightly different footnotes for this table.

Just some information for thought.

Peder Golberg, P.E.
Portland, Oregon.

At 03:08 PM 1/28/2000 -0800, you wrote:
>At 07:17 AM 01/28/2000 -0800, you wrote:
>>UBC Table 23-II-I-1, footnote 3 clearly has the minimum requirement for"all
>>framing members receiving edge nailing from abutting panels shall not be
>>less than a single 3-inch nominal member (for allowable shear >350PLF)" This
>>would clearly indicate that 2-2x's are not acceptable. As an alternative,
>>4x's may also be used.  In the 5 jurisdictions that we do the Building
>>Department administration for, 2-2x's are not acceptable. Conceder is
>>failure occurred how 2-2x's instead of the required minimum single 3x would
>>stand in a court of law.
>>Thanks Tom
>Well, I'm considering that last sentence. How _would_ a court of law figure
>what the code means? Plain meaning of words is the court's first resort, but
>as usual, the code in this is "clearly" inarticulate and ambiguous. Also,
>the code itself gives the power of interpreting the code to the local
>building official, and such interpretations are often elusive, when not
>requested ahead of time, and tend to vary. Courts however can override
>administrative officials as to what law means. 
>But the court would tackle the question as a subordinate part of some bigger
>issue, such as determining if someone was negligent and it harmed someone
>else. Certainly the court would rely substantially on expert testimony. 
>Lots of opinion already expressed on this list says that resistance to
>splitting due to multiple nail lines is why 3x lumber is in code. Dividing
>the nail lines into two separate 2x pieces does admit of rational analysis
>in accordance with accepted principles of mechanics, per Chap 16, and on its
>face addresses the splitting problem cited. The code does allow alternate
>means of materials construction than the one specified, if equivalent or
>better. Lastly, neither of the 2x's receives edge nailing from panels in the
>plural, only from a single panel, so there is semantic support for use of
>two-2x after all. The "member" that receives nailing from _both_ abutting
>panels is a two-2x nail-laminated member, which is "not less" dimensionally
>or functionally than a single 3x. I see code compliance here. 
>As for use of super-fine-print footnotes to add more stringent exceptions in
>code (instead of merely adding explanations or less stringent exceptions by
>footnote to what's in the code body): This is a deplorable practice that
>ought to be outlawed. This sorry, deceptive habit was called to my attention
>by a Calif SE friend while he was in law school. Now he hires out to get us
>out of the trouble our pals in codewriting help get us in to.
>Charles O. Greenlaw  SE  Sacramento CA