3x4 & 2x5 wood studs

[Francis Vineyard]

Reference Table R602.3(5) permits 3x4's and 2x5's studs up to 10 ft. in height. Are they still used or available?

It appears 3x4's are popular in the west; are they 2-1/2 x 3-1/2 or 2-3/4 x 3-3/4?

 

[mark handler]

3x4's =====> 2-1/2 x 3-1/2

2x5's =====> 1-1/2 x 4-1/2

Remember 19% max moisture content lumber, does shrink, so with less moisture content, you could end up with 1/4 's

 

[jdfruit]

3x4 is commonly available including treated for shear wall sole plates

2x5 is special order, just checked with my friend at a large lumber yard, non standard board size order is on "90 days to forget it" basis; if you don't get it in 90 days you most likely won't get it.

 

[Francis Vineyard]

Follow up question if you don't mind; contractor wants to double 2x4's in place of 3x4's to support two floors, plus a roof-ceiling or a habitable attic assembly; this is or not equivalent?

 

[jdfruit]

2 2x4 = 3" net x 3-1/2" net; larger than 3x4. Ok for vertical bearing equivalency. Need the studs "stitched" together so narrow dimension deflection under load is controlled; I usually accept 16d at 12" oc. For short riser walls between foundation top and floor frame bottom, if the stud length is less than 14" then solid material required with narrow dimension equal to required stud depth (AFPA NDS requirement)

 

[Francis Vineyard]

jdfruit; that's more information provided on the engineer's forum that debated the load bearing capacity more than the axial load capacity with the sheathing.

Thanks again.

 

[mark handler]

Follow up question if you don't mind; contractor wants to double 2x4's in place of 3x4's to support two floors, plus a roof-ceiling or a habitable attic assembly; this is or not equivalent?

The requirement is usually due to the spacing of the nails/bolts. it can be an issue of reduced values if you use two members because the nailing is no longer at the boundry, it is moved in to the panel. and wont work with plate bolting, Work with the engineer.

 

[MASSDRIVER]

I just use 4X4's, with a 3X sole plate. It's cheaper than the 3x material.

Never once have I run into a 2X5, and might possibly set an architect's car on fire if he were ever mean enough to do that to me.

Brent.