The framing starts this week, and I just want to be sure we do it right.

Wouldn't the safest bet be to frame it the way the architect said and the plans that were passed show?

I'm not sure why you'd feel the need to second guess this. It'll only save you a couple of bucks in timber. Or is there some other cost that you'd be saving that I'm not thinking of?

IMO building strictly to "meet code" is a huge disservice and while you CAN, why WOULD you?

You're looking at the table for 10 ft tall studs. For studs heights above 10 ft, TABLE R602.3.1 limits the height of 2x4's @ 16" o.c. to 12 ft. assuming the following:

the studs support a roof only; wind speed will not exceed 100 MPH; snow load not exceeding 25 psf; fb not less than 1,310 psi determined by multiplying the AF&PA NDS tabular base design value by the repetitive use factor, and by the size factor for all species except southern pine; E not less than 1.6 × 106 psi, tributary dimensions for floors and roofs not exceeding 6 feet; maximum span for floors and roof not exceeding 12 feet; eaves not over 2 feet in dimension and cover with exterior sheathing.

Also, Utility, Standard, Stud and No. 3 lumber grades of any species are not permitted for any stud regulated by the table.

In my experience, it is common to see a poor quality and incorrect grade 2x4s on a job site; it is difficult to monitor the grades unless you are on the site every day; and I would not assume the weather would always cooperate.

If I were the architect, I would specify 2x6s for an 11 ft wall regardless of the other variables or what the building code says since it would be my stamp on the drawings.

Richard, you are the wealth of knowledge...

It shouldn't matter unless the inspector objects.

The greatest talent is knowing where to look.

What is the problem with 12" oc vs 16" oc? A few studs and narrower batts. I would stick with the architects recommendation - tell him you now want 2x6's. Although he may still want 12" oc.

I had a contractor decide he knew better on a deck - and he changed the angle of the decking material, not realizing that around the corner the new angle would not work. The architect knew.

I really don't want to do stud spacing at 12" o.c., so I'll go ahead and frame with 2x6s at 16" o.c. instead.

Okay so it's not a cost savings reason if you're willing to go to 2x6s instead.

Can you satisfy our curiosity and let us know why you are so opposed to 12" o.c.?

In the 2012 IRC 2x4 studs are limited to 12 ft. at any spacing and 2x6 studs are limited to 16 ft. at any spacing and 18 ft at 16" or smaller spacing..

This increase in allowable height is because a stud spans vertically from sole plate to top plate and the additional depth of a 2x6 increases the stud's resistance to bending by 250%. (Section Modulus of 2x4 = 3.06 and 2x6 = 7.56).

The architect is apparently trying to save cost and/or space by decreasing the spacing or he is adjusting for some other condition we are not aware of. But the 2x6's are so much stronger than 2x4's that they can even be installed at 24" o.c.

The architect has already agreed to the change, he just doesn't have time to change the drawings. I find it odd that this change would require revised drawings. Stud spacings other than 16" o.c. are normally just noted on the floor plan and can easily be changed by a simple written change bulletin from the architect emailed to the owner who could then submit it to the building department.