Proper size of header to support new door in load bearing wall?

Question

We're going to install a new linen closet off the hallway next to our recently(ish) remodeled bathroom. The wall in question is load bearing.

I know how to properly build out the King and Jack studs, and if this weren't load bearing I'd just put in cripple studs, but since this is load bearing I figure on installing sistered 2x? over the doorway resting on doubled up jack studs. The only question I have is - 2 by WHAT?

It's a 30" door if I recall correctly (it's reclaimed from another part of the house and I haven't measured it lately) so I'm thinking sistered 2x12's will be MORE than sufficient.

Answer 1

International Residential Code 2012

Chapter 6 Wall Construction

Section R602 Wood Wall Framing

R602.7 Headers. For header spans see Tables R502.5(1) and R502.5(2).

So if you're on the top floor, you can use 2 2x4's (unless the building is 36' wide, in which case you'll need 2 2x6's). If you have a floor above, you'll need 2 2x6's (unless the building is 36' wide, in which case you'll need 2 2x8's).

Answer 2

Older buildings are 2X4 up and downstairs. Codes have changed, so remodeling will be a hassle if the permit inspectors don't know the history. Remodeling a 1950's house in ca, the planning guy was really helpful and gave me the strength for an open attic! I was told it was The actual strength or the amount of "wood". AKA: 2 x 4 is 1 1/2 x 3 1/2 = 5.25 sq in. A 2X6 = 8.25si So you'd need 2 2x4's to replace a 2x6. A simple call to a decent Planning Dept would answer that question. 1) Over-building always gives you a good impression with the inspectors. 2) Asking the Inspector first gives them the added impression you're trying to do things right!