Equivalent wood grades
Equivalent wood grades
(OP)
From the 1967 UBC table No 25-A (page 165), for Douglas Fir, Coast region species, what is the equivalent grade for a No 2 DF joist? Have the grade designations changed since 1967? Here are the ones currently in the document for the species I mentioned:
Select Structural
1750f
1500f
1200f
....
No mention of the regular No. 1, No.2 etc. grades... Any ideas?
Select Structural
1750f
1500f
1200f
....
No mention of the regular No. 1, No.2 etc. grades... Any ideas?






RE: Equivalent wood grades
RE: Equivalent wood grades
Dense Super-Structural
Super-structural and dense structural
Structural
Common Structural
I tried to post a picture but the attached will have to suffice. This old book is fantastic if you can afford it. It's not too bad.
Does this help?
RE: Equivalent wood grades
Just out of curiosity, do they give the allowable stresses in your book?
RE: Equivalent wood grades
RE: Equivalent wood grades
RE: Equivalent wood grades
RE: Equivalent wood grades
Take a look at the NDS (National Design Spec. for Wood Construction, or NDS for Stress-Graded Lumber and Its Fasteners) and its various Supplements (various supplement years) for the specific wood grades and design stresses. That’s what would most likely have been followed for the design of a wood structure at that time. Not only do you have to pay attention to the species, but also to the grade name and then the specific grading agency in some cases. See if you can find some grading stamps on the members, for starters. Then, what NDS and its supplements was being used at that time, in your area? The UBC essentially copied the NDS, literally word for word, at that time. In fact, copies of the UBC from that time contained the complete AISC, ACI and NDS codes, and others, within its covers and it could be carried in one hand. 5.5"x8.25" high by 1.75" thick; it was reasonably affordable, usable and understandable too. Ah... for the good old days. The allowable stresses and the mech. properties have continued to decline in value, over the years, as we’ve learned some new things about wood, and as we are cutting younger and younger trees for lumber, wood quality has deteriorated.
RE: Equivalent wood grades
I am somewhat hesitant to post this link to old UBCs. But, I am assuming UC Berkley's Library respects all copyrights. Perhaps, they have permission, or the copyrights have lapsed.
1927-1961: http://oskicat.berkeley.edu/record=b23228862~S52
1967-1994: http://oskicat.berkeley.edu/record=b21478979~S1
If anyone thinks it violates any intellectual property rights, please red flag this post!
RE: Equivalent wood grades
I think, and don't quote me, but I think the old codes may be available via FOIA. Codes were law at one time. We have a right to know what the law is. If someone knows this for sure, please comment.
Btw, FOIA is freedom of info act for those of you in Rio Linda
RE: Equivalent wood grades
There is public e-codes here: Link
Not sure if it has what the OP desires.
RE: Equivalent wood grades
Unfortunately, I do not have anything earlier.
Mike McCann, PE, SE (WA)
RE: Equivalent wood grades
RE: Equivalent wood grades
Mike McCann, PE, SE (WA)