Solid Post or Multiple Studs?
Solid Post or Multiple Studs?
(OP)
I have a Client who is insisting that using multiple studs in a framed wall (residential construction) is the same as using a solid wood post that equates to the same dimensional lumber. For example, he insists that (2)2x4 spf#2 studs nailed together will support the same vertical or lateral loads of a 4x4 post.
How do I convince him that he is wrong?
Thanks..
How do I convince him that he is wrong?
Thanks..






RE: Solid Post or Multiple Studs?
RE: Solid Post or Multiple Studs?
RE: Solid Post or Multiple Studs?
RE: Solid Post or Multiple Studs?
However, if you run the numbers, you may can get adequate strength from the doubled/tripled studs, and not need the 4x4s. That may be the point your client is making.
RE: Solid Post or Multiple Studs?
I am sure results from actual tests comparing built-up to solid compression members were used to modify the column stability factor.
Question: While 2-2x4s do not have the same axial load carrying capacity as 1-4x4 post, for conventional wall construction do bldg depts sometimes accept 2-2x4s as an option where 1-4x4 is required?
RE: Solid Post or Multiple Studs?
RE: Solid Post or Multiple Studs?
ww
RE: Solid Post or Multiple Studs?
RE: Solid Post or Multiple Studs?
Nice link to a popular question. I usually let it go if the the double 2 x studs are blocked at mid-height for the entire wall.
RE: Solid Post or Multiple Studs?
akastud
RE: Solid Post or Multiple Studs?
The theory, as I understand it, is that as a dual 2x4 column receives axial load, the limit state of lateral buckling is restrained by the cross sectional stiffness (Euler buckling, etc) and this lateral stiffness depends upon a composite-like behavior between the two 2x4's. For this to happen, the nailing between the two must be of sufficient strength and stiffness to resist the longitudinal shears that develop.
But if your built-up column occurs within a wall, with sheathing on either face, then the potential to buckle is negated and the reduction factor can be ignored. This means that the 2-2x4 column behaves exactly like a 3x4 column (2 x 1.5 = 3) except for the points made above about 2x4's having different allowable stresses than 4x4's, etc.
RE: Solid Post or Multiple Studs?
RE: Solid Post or Multiple Studs?
But you're right - some buildngs have lots of shearwalls with multiple end posts. But even those have an axial compressive purpose as the shearwall is loaded.
RE: Solid Post or Multiple Studs?
Often shear wall ends use Simpson HD2A, I have seen in CA they used 4x4s, in FL they only use 2-2x4s. Is the sesmic and wind loading treated differently?