The International Residential Code indicates the use of 3×4 @ 16″ O.C. studs when supporting 2 floors, roof and ceiling. I also could use a 2×6 @ 16″ O.C. studs but due to space limitations I would like to use a 4″ wide wall. Does anyone know if I could use doubled 2×4 studs @16″ O.C. to meet the code? What nailing pattern do I use to fasten the double studs together?
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Don't have an answer for you, just another question--maybe using 4x4's would be cheaper and easier than double 2x4's with the messing around with nailing them together and such? Drilling holes for wires and such would be a pain using either system though, wouldn't it!?
I don't suppose there is any chance this is a misprint or typo? I haven't ever seen a 3x4
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3x4"s were very common years ago for concrete formwork. They were used for pudlocks ( joists) to support the plywood forms under the slab. Other than that ,I never saw a 3x4 used in residential work.They actually measured 2 3/4"x 3 3/4" and were sawn but not planed.
mike
So doesn't it also seem strange to you that the IBC would suddenly make a non-typical requirement without common precedent, using a practicaly non-existant material to build homes?
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> .... a non-typical requirement without common precedent, using a practicaly non-existant material ....
How international is this Interntnational code? Could it be that 3x4 and 2x5 are dimensions used elsewhere in the world?
-- J.S.
this just hit me too...any lumber in a building (shed, barn, house ) MUST be KD if OVER 2'' in thickness...in order to have ELE.
Maybe not everywhere, but where I was in Western NC, it was true.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
OK - I give.... what's ELE?
Matt
ELE= power
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Not to change the subject but can't find the discussion where I said that both okra and another thing that starts with 'o' were slimey--didn't mean to denegrate okra. My wife likes it, I am a little put off by its texture.
I can live with out it, I ain't that much of a cracker yet...
Had some of the best on my buddy's house boat in NC...weren't slimey at all...the secret is...SHARP knife, ONE slice...don't saw thru it.
Funny the things ya learn. His wife could cook up an old boot, and it'd taste like filet mignon..or what ever we managed to drag onto the houseboat from the lake.
The thread was DRIP EDGE....
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
"this just hit me too...any lumber in a building (shed, barn, house ) MUST be KD if OVER 2'' in thickness...in order to have ELE.
Maybe not everywhere, but where I was in Western NC, it was true."
Definately not true here in the Pacific Northwet, Sphere. Most of our sawn beams are still Douglas Fir, and I don't know if I've ever seen anything besides 2x KD...and that is highly unusual...much more commonly "SDry" which I'm pretty sure stands for "surface dry" (to 18% or something).
We often get KD "Hemfir" (a combination of alpine firs, hemlock, maybe some spruce?), but they don't grade out anywhere near as strong as DFir. For example, many specs call out "...4x12 header, #2 DFir or #1 Hemfir..." or something like that.
LVLs and I-joists are making significant inroads as everyday structural members here, but I'd be surprised if we exhaust the supply of DFir out here in my lifetime.
Came back to say that I'm almost positive I remember framing a retirement home in Puyallup in the early 80s with 3x4 studs on the bottom floor, then 2x4 for the upper two floors. I don't think that was unusual, but I didn't stay in the union long so I didn't do a lot of commercial wood framing.
Yeah, now that I think about it, I'm certain that's how we built that building.
Edited 9/9/2004 9:12 am ET by jim blodgett
NC makes up the rules as they go..LOL
"SDRY" means it was "surfaced" when dry..not that it IS dry or KD..I ferget what that actual % is..but you are probably in the ballpark.
IOW the other stamp seen is "SGRN" means it was planed to size when green, not airdried.
You can tell by the quality of the planing sometimes whether it was green or AD when sized..AD is a bit smoother, where green is often stringier looking. But where you are it could be different, cuz nothing EVER gets REALLY dry right? LOL
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
I think technically he probably could use double 2x4s, but using 4x4's would be a bad idea--95% of square stock is cut from the tree's heart and you know how that twists as it dries.... I don't wanna think about trying to deal with repairing gyprock hung on a bunch of 4x4 studs six months down the road....
It actually shouldn't be that hard to get a load of 3x4 custom cut from his local sawmill; but I would definintely follow up Piffin's question before signing any special orders....
If it turns out they really require 3x4s on 16s, he stands a pretty good chance to get an upcheck for 2x4s on 12s. He'd only be shy 1" nominal beef in 48" that way. If he specs SS from the yard, the BI might buy it if asked nicely in advance....
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
Yes, it's true that IRC requires 2x6 or 3x4 16" O.C. for basement walls or cripple walls supporting 2 stories above... I've only seen 2x6s used though. You have some ideas, so at this point you have to get the buyoff of an alternate plan by your local inspection department. What any of us here think is not gonna get your framing inspection signed off. Some inspection departments I deal with are kind of chicken though and won't accept anything not specified in the code without an engineer's letter.
Here is the table from 2000 IRC
2x4 - Roof and ceiling - 24" oc
- roof, ceiling, 1 floor - 16" oc
NO - 2flor entry.
3x4 - roof & ceiling - 24"
- roof, ceiling, 1 flr - 24"
- roof, ceiling 2 flrs - 16"
2x5 - roof & ceiling - 24
- roof, ceiling, 1flr -24"
No - 2 floor entry
2x6 - roof & ceiling - 24"
- roof, ceiling & 1 flr -24"
- roof, ceiling & 2flr -16"
As I read it this is the generic requirments for any stud walls 10 ft or less.
I am not a pro, but this does sound strange to me. Million of 2 story house with 2x4 walls.
There are other tables for seismic and wind rquireemnts for taller walls.
WOW! I sure appreciate everyones help. As Matt said, I have some ideas to take to the BI. Thanks for pointing out table R602.3.1. It's for studs longer than 10 feet but it makes sense to me that it should work for studs less than 10 feet. I know, there I go thinking. So far I have about 5 approaches to take, which all use a 4" wall. I'll talk real nice to the BI. THANKS again everyone.
The 2000 IRC code allows two floors and a roof to be supported by 2 x 4 studs, 12" OC as long as they are less than 12' long.
Refer to Table R602.3.1
Utility, standard, stud and #3 grades are not permitted.
No, unless I am misunderstanding it.
Section R602.3.1 is for stud spacing and it calls out table 602.3(5) for walls less than 10 ft which is what I posted above.
And table 602.3.1 for walls greater than 10 ft.
And 602.3.1 has 3 sections, Supporting roof only (and I assume ceiling), one floor and roof, and 2 floors and roof.
Only the first section (support only roof) allows for 2x4 studs.
For 2x4 and 10-12 ft height you can go with 24" OC, for 12-14ft you can use 16" OC and 14-18 ft 8" OC.
Now of the 2 story or higher allows for 2x4 usage.
You are correct in your assumption that the table specifies stud spacing - however, it also allows the use of 2x4 studs on 12" spacing for supporting two floors plus a roof and therefore 2 x 6 studs are not required.
It also allows the use of 2 x 4's up to 12' as shown in the left hand column of the "supporting two floors and a roof" section - line one of this section is for studs >10' (greater than 10 feet); line two is for studs 12' and longer which require 2 x 6 studs
I would use 4x4's. The nailing pattern that I would use would be two 3"x .131 nails every two feet.
I work on a barracks for the feds where we had to use 3x4's for studs due to the nailing pattern on the sheathing. I can't remember where we got them from.
Sorry, Dave
I have a pre 1900 house with 3x4 studs hand cut with 20in to 40in oc.
Ceiling Joices 5 x 8 with 24in to 28in oc.