jpranch
Platinum Member
Would anybody have the Fb values for #1 Douglas Fir, kiln dried that is 16” & 18” tall x 1 1/2” thick nominal??? Normal duration.
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Flex in bending for nominal lumber? Need help.
- Thread starter jpranch
- Start date
jpranch
Platinum Member
I would expect that number to be over 2,000?
fatboy
Administrator
Looks like 1300-1350, for #1, depends on South or Larch.
https://www.google.com/url?sa=t&rct...QffpFjLow&sig2=LUc71MUo8IRYUGE3XQgH3Q&cad=rja
https://www.google.com/url?sa=t&rct...QffpFjLow&sig2=LUc71MUo8IRYUGE3XQgH3Q&cad=rja
Phil
Registered User
fatboy - that table is for beams and stringers. Here are some definitions
Dimensional Lumber: 2"-4" nominal thickness and 2" or more in width
Beams and Stringers: 5" or greater nominal thickness and width more than 2" greater than thickness
Posts and Timbers: square of approximately square, 5x5 nominal or larger and width not more than 2" greater than thickness.
1-1/2 x 16 or 18 is an odd size (1-1/4 thick)., I think it would be classified as a board but still use the dimensional lumber design values. I recommend calling the WWPA to confirm. The reference design values are in the NDS Supplement, http://www.awc.org/pdf/codes-standards/publications/nds/AWC-NDS2015-Supplement-ViewOnly-1411.pdf .
DF dimensional lumber is on page 35 (pdf page 42). See Table 4a footnote 2 about boards. If it used as a joist of rafter (closely spaced repetitive member) the reference design value can be multiplied by 1.15. If it is used flat (like a deck board) the reference design value can be multiplied by 1.2. For more information on adjustment factors, see section 4.3 of the NDS http://www.awc.org/pdf/codes-standards/publications/nds/AWC-NDS2015-ViewOnly-1603.pdf
Dimensional Lumber: 2"-4" nominal thickness and 2" or more in width
Beams and Stringers: 5" or greater nominal thickness and width more than 2" greater than thickness
Posts and Timbers: square of approximately square, 5x5 nominal or larger and width not more than 2" greater than thickness.
1-1/2 x 16 or 18 is an odd size (1-1/4 thick)., I think it would be classified as a board but still use the dimensional lumber design values. I recommend calling the WWPA to confirm. The reference design values are in the NDS Supplement, http://www.awc.org/pdf/codes-standards/publications/nds/AWC-NDS2015-Supplement-ViewOnly-1411.pdf .
DF dimensional lumber is on page 35 (pdf page 42). See Table 4a footnote 2 about boards. If it used as a joist of rafter (closely spaced repetitive member) the reference design value can be multiplied by 1.15. If it is used flat (like a deck board) the reference design value can be multiplied by 1.2. For more information on adjustment factors, see section 4.3 of the NDS http://www.awc.org/pdf/codes-standards/publications/nds/AWC-NDS2015-ViewOnly-1603.pdf
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fatboy
Administrator
I was giving him a starting point.............. I saw the heading on the table, and know what it meant.
steveray
SAWHORSE
If you were a customer, I would tell you the answer is "hire an engineer"....Because I don't have time to find that answer..But I might be able to run it through beamcheck if you can give me all of the info...
jpranch
Platinum Member
Steveray, and fatboy, that is what I ended up doing. Got a structural engineer review and stamp the plan. Turns out that it was timber framed. The framing plan wasn't much to say the least until the engineer got involved. Thanks.
steveray
SAWHORSE
I see that a bit...Seems like everyone is just supposed to accept that the timber framers know what they are doing....I tell them it will be a lot faster and easier with an engineer or give me lumber sizes and a way to verify them...