3/17/2024 0 Comments Southern pine span tables raftersThe first one is a quick 1 page overview one is a good bit longer but goes into more depth describes the annual and in grade SPIB monitoring process is from one of the FPL's basic wood anatomy publications"Juvenile wood in softwoods is in part characterized by the production of axial tracheids that have a higher microfibril angle in the S2 wall layer (Larson et al. These are a couple of good ones I remembered from there. ![]() If you want to read more on the wood tech side of this go to the FPL website and search for juvenile wood in the keyword search. The current problem really predates hurricane Hugo and is a result of our silvicultural practices. Please do keep us in the loop as this develops. This further reinforces my feeling that this is a grading rather than a species issue. We walked out into the yard and I flipped through a bundle pointing out the large proportion of reaction wood in the pack. This is also not restricted to SYP, I gnawed on my supplier a week ago over a bundle of NS that he sent out. Depending on how the sample set is picked when setting up an MSR run the bending strength values of the wood could be erratic IMO. Fb, bending strength, is derived from MOE, stiffness. Reaction wood in softwoods is unusually stiff for its' strength. I'm also not sure that this will not affect MSR lumber. Allowing one strength controlling defect to go unchecked into the grade is what is causing this proposed ade out that defect. If instead of derating the species the grade rules tightened up the exclusion requirements of these types of visibly apparent inferior wood this would solve the problem. The NLGA rules are weak to the point of being effectively silent on the inclusion of compression and juvenile wood within a grade. Right now I don’t have any specific details and prefer not to cause a lot of concern when it is not needed.įrom what I see in the field this is more of a grading issue than one that requires derating of the species. MSR lumber should not be affected by this change from what I have been told so far.Īfter they publish their recommendation I plan to send the group an e-mail about what should be done in the short term and long term. The timber is being grown so fast that the old published values are not being met. The problems stem from new growth lumber and brash failures. The results/recommendations of their investigation are to be reported on Oct 21. They found our results to be a valid concern and took over there own investigation. Our industry turned the test result over to the So Pine folks and suggested they look into it. During the test the lumber kept failing before it was suppose to. We should know something in about 1 week.Ībout 1 year ago there were full scale truss test performed by our industry. ![]() No one that I have talked to expects the change to be implemented any latter then 90 days. The rumor on the streets is that it will be sooner rather then latter. I personally expect the change to be implemented in 21-90 days after the announcement. As I’m sure you are aware the span tables in the code could be invalidated once they publish the new standards. ![]() The million dollar question is, when will this be implemented. I expect SYP visual graded lumber values (not just MOE) to be reduced up to 30%. The final discussion will be taking place on Oct 20 with a publication of their decision on Oct 21. When I heard about this I emailed him and here is his email back to me. I am pretty good friends with one of the engineers that works for the Universal Forest Products. Apparently all these years we thought that pine was the strongest of all wood.
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