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Re: Common versus box nails

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In a message dated 6/17/99 1:32:06 AM Pacific Daylight Time, 
RShreenan(--nospam--at) writes:

<< I am reluctant to totally blame the framer even though the U.B.C. section 
 the complete nailing spec was referred to.
 My experience has been that there was enough confusion in the construction 
 indusrtry regarding nail types in that time period that I would then and now 
 feel negligent if I did not specify "common nails only" in my plans or specs.
 I also believe that referring to the U.B.C. to determine nail types is a 
 cop-out and the construction documents should be clear and complete 
 materials and fasteners.  If this is done properly, the contractor has a 
 chance of getting it right.  If it is not, the results can be costly.
 This is a great forum for the exchange of ideas and opinions and your 
 responses were helpful and greatly appreciated.  
 I am guilty of being one of the "lurkers" but I promise as soon as I feel I 
 can contribute or help someone with a problem, I will.
 Best regards,
 Ray Shreenan >>

At this time, the contractor is not required nor expected by certification to 
have specific knowledge of the UBC.  This may free him of the responsiblity 
to have specific knowledge as to how a diaphragm (horizontal or vertical) 
should be properly nailed.
However, I don't agree with this for the perspective that the majority of the 
damage evaluated after major seismic and wind events have been  construction 
quality issues.
Although it would seem that the engineer is responsible for specifying each 
and every element in the code that is to be used on the job, I believe this 
is a handicap that can and does create liability for the engineer. IMO, it 
seems that it should NOT be necessary for the engineer to recreate the code 
on his plans each time a project is designed just to spell out to a 
contractor something he should know in the course of performing his trade.
Although I believe this, I realize that it is not practical at this time nor 
is it required of the contractor.
For this reason, I am an advocate that anyone who lifts a tool to construct a 
structural system should be educated and certified in the conventional 
erection of the materials of his expertise. In otherwords, if the framer is 
building wood buildings, he should know that Common nails are to be used in 
the construction of a diaphragm. He need not interpret the size or spacing, 
but he should possess the basic knowledge that the code requires a Common 
nail over a box nail. He should also know the difference between the two 
nails but should not be expected to inteprete the additional load due to 
shank diameter and head area.
For the same token, he should know where blocking is to be placed, the 
minimum spacing and number of anchor bolts (minimum end distance), top plate 
splices, number of trimmers for specific widths of openings etc. 
Expecting the engineer to provide all information on the plans is inviting 
litigation. This is not to try and pass responsiblity, but intended to 
suggest that what has recently been identified as the weak link, be required 
to improve with continuing education or specific certifications.
Dennis S. Wish PE