Studs 24" On Center?

[billconner]

I'd do everything on 16" centers myself,including the roof.
I've walked on enough of other people's sketchy 24 on center roofs around the midwest,no thanks.

Well, sure if they're using minimum sheathing.

 

[ToolsRCool]

A lot of great input. Much appreciated.

 

[Jim greengo]

Well, sure if they're using minimum sheathing.

I remember when they used to use 1xs for roof sheathing,and then 3/4" plywood was the next big thing.
I don't trust that that osb **** they use with clips these days,especially on 24" centers.

 

[billconner]

I remember when they used to use 1xs for roof sheathing,and then 3/4" plywood was the next big thing.
I don't trust that that osb **** they use with clips these days,especially on 24" centers.

I used rough sawn pine - full 1" - and could drive a car on it. I detest flimsy roofs that code allows.

 

[acer66]

I used rough sawn pine - full 1" - and could drive a car on it. I detest flimsy roofs that code allows.

That is how my house is build.
All real 2x4” 24” o/c with proper raw sawn 1” boards walls and roof.

What I add of modify is 2x6” 24 o/c with green zip and roof is 2x12” 24” o/c with red zip.

While the roof is a bit soft, not that I am heavy or something, but I never had a problem.

 

[Innovate1]

Several folks mentioned "cutting down thermal bridging". Cut it down to ZERO by adding 1/2" POLYISO on the inside, under whatever you're sheeting the interior with. On the good shop that I moved away from, I used 1". It could be -15 outside and you could lay your palm on the drywall and it was room temperature. Also, you mentioned R23 in the walls. So apparently, you're using mineral wool? Have you looked into dense pack cellulose? At 5.5", you would have R22 at probably half the cost. Just another option for you.
Look at my old build thread with the link that's still down there. v

You make good points but you are never going to reduce thermal bridging to zero unless you have uniform cross section in the wall - i.e. no studs. Even with 2 x 4s on alternating walls and locations in a 2x6 space the studs conduct more heat to the other side than the areas with just insulation. It does reduce it significantly but it's not zero.

 

[Dragfluid]

You make good points but you are never going to reduce thermal bridging to zero unless you have uniform cross section in the wall - i.e. no studs. Even with 2 x 4s on alternating walls and locations in a 2x6 space the studs conduct more heat to the other side than the areas with just insulation. It does reduce it significantly but it's not zero.

OK, not zero. But a whole hell of a lot different than buildings without anything like that!
That shop was 42x72x14. It was heated with an 80k hanging propane furnace. And in below zero temps, it wasn't running constantly, either.

 

[i4ni]

I built a 26 x 40 with 2x6's on 24" centers and the 1/2" sheathing cupped so much I had to put in blocking to straighten the cupping. Should have went 16" centers to begin with.

 

[tarmy]

I bought a place with 24”OC trusses. If I had built it myself…16. I insulated it and hung 5/8” drywall and didn’t have any sag. Around here they required 12” OC on 2x6 wall for snow load.

 

[walta]

If you Google “advanced framing” you will find a ton of info about this system. 24 inches on center is the most obvious difference but there are dozens of other changes they go with it. Like fewer boards in every corner and window opening.

The question in my mind comes down to how will it sound when you slam a door verses a few better R value. Assuming both wall will be 2x6.

BSI-030: Advanced Framing | buildingscience.com

buildingscience.com

Walta

 

[Innovate1]

Thanks for all the replies, good points on each side. It all lines up with the little I have learned on it so far, so good I did not seemingly miss anything.

I did not consider to factor in insulation cost for a 16" 2x6 wall cavity (R-23 batt) vs 24", on a $/area basis. Will check that.

Understanding on double top plates was same, that is really for when rafters or trusses and such land in between studs. 24" OC for all really seems to make sense from this perspective.

This then goes even a little more sideways, because I am reading up on installation manuals for cement board T1-11 (Hardi-board), and it says their preference is to double up studs on every 4' mark, so the end flange of each T1-11 fiberboard sheet can rest on a full 3.5" board edge vs half of that, and not have the edge crumble when taking a nail. I get it. So, part of where this was going, was to do 24" spacing, and doubles ever other. So, probably even more total studs than 16" OC spacing, but nice double-width edge studs at siding sheet seams, yet not as many total studs and weight as if trying to do the same @ 16" OC and doubles @ 48".

Jury still out on all of it, just thinking out loud. Thanks for all input.

I did 16" on 2 x 6 studs and 24" on trusses. I ended up with a number of shorter spaces due to windows and an interior wall. If I really wanted to optimize I could have adjusted the window positions slightly to line up at least one end on the 16" spacing. Those spacings are pretty standard here but we don't get a lot of snow. 7/16 OSB with clips for the roof as I recall and haven't had any issues.

Instead of double studs I would consider using a 2 x 4 on the inside and then another 2 x 4 flat against the outside surface (if acceptable to your AHJ). This gives you the nailing width and less thermal bridging and cost than two 2 x 6. It will need a 1/2 plywood spacer between them to match the 2 x 6s. I would stick with 16" stud spacing with a double top plate. The overlaps add a lot of strength. You likely get much more snow than here so I am not going to make any suggestion on truss spacing.