Minimum throat depth for conventional wood stringers

[Michael Thomas]

Does the IRC specify a minimum throat depth at stringers cut from conventional lumber, or is there another source for such recommendations? (I can find a lot of information on-line for engineered wood products used as stringers, but nothing for conventional sawn lumber...)

Thanks.

[James Duffin]

I don't see anything in the NC code about stringer size....

[BARRY ADAIR]

might get shot for this but as i recall from wood framing days

Throat depth:
3½” for 9½” stringer
5⅞” for 11⅞” stringer
8” for 14” stringer
Lumber should be Min. No. 2 hem-fir, spruce-pine-fir or better grade

let the bullets fly

[Brandon Whitmore]

Barry,

That's what is called for by Boise Cascade for their Versa- Lam stringers. http://www.bc.com/dms/wood/ewp/3_Guide_Resources/west_us/8_West_Stair_Stringer/1-5_16-VL-1_4-1800-west-stair-stringer-guide-w_superstep/1-5_16%20VL%201_4%201800%20west%20stair%20stringer%2 0guide%20w_superstep.ptdddddd

I've seen both 4 and 5" min. called for with conventional lumber, so I am curious as well.............The American Wood Council calls for a min. 5" throat: http://vil.albion.ny.us/content/Departments/View/1:field=documents;/content/Documents/File/51.pdf Fig. 28