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FWIW,I was told a 2x6 ridge beam would be good enough, but I would like more opinions. Do you think that 2x6 is good enough are what. Any help would be appreciated.
Thanks, Mike
"Roof ridge beam deflection greater than 25 mm in 2400 mm is considered excessive ."
This is a 1 in ~100 ratio, so Δ/L=5/384 * w[L^3]/EI = .01, so w in pounds/inch distributed load is 0.768EI/[L^3]
L is 24(12) = 240", E assumed to be 1,000,000 PSI, I = [1/12] b[h^3] = [1/12]1.5[5.5^3]= 21 in⁴.
I get 1.2 pounds per linear inch, 290 pounds for the whole ridge beam, dead & live load.
That seems small. Maybe there is an arith error.