Structural framing query

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The above example is intended to show that it is possible to design unconventionally framed structures to save labor, but they must be properly engineered.
Agreed and without dispute. In this particular case, the owner wanted to explore different ideas/designs with respect to labor costs.
Relative to Bobk207's answer of; Pretty hard to beat stick framing & wood sheathing for speed of construction & minimal labor. Gun nails are faster than screws.
While the above is true, the owner has no desire to include interior/exterior wood sheating. In addition, it's faster, and less expensive, (material/labor) to build the walls on a slab and fasten diagonal shear metal banding (interior/exterior?) with screws then to cut/install diagonal 2x6 shear bracing into the walls.
There's no doubt in my mind a Licensed Engineer needs to look at this and approve of it, for comfort of mind if nothing else. Irrespective of that, I still have a need to know whether this would a viable alternative. In my mind, I don't see the 1x4 proposal being as solid as stick framed with exterior wood sheathing. To that degree, I wonder how much structural integrity will be lost by using the 1x4's on the face of the studs, with structural metal ribbed panels on those, as opposed to using OSB on the studs. I can 'see' the metal panels being worth next to nothing (shear) as they would depend on the 1x4 connections to the wall studs.
I have no idea where this will wind up, but if it gets wierd, out of scope and approved, I'll definitly post some dwg's someplace for all to see.
Thnx to all for posts.......................
Dan
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Dan Deckert wrote:

True, but if you have an auto feed screw gun and you deduct for all of the nails that missed the framing (nail gun cowboys), it's probably close to a wash.

Cutting a let-in brace should take, what?, ten minutes if you're loafing. I can't see how the difference between one type of bracing and the other would have any real impact on the budget.
R
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R- Keep the cowboys away from the nail guns & just tighten up on the nailing schedule slightly, don't worry about the few misses, nobody fixes them......btw don't all shearwalls get nailed at about 4" independent of what the dwg says; 3, 4 or 6? :)
cheers Bob
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Bobk207 wrote:

Not if I'm around. Even a few misses compromises the strength, although I don't worry about the odd miss here and there. It's the row of missed nails that pisses me off.
R
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R-
Yeah, a row of misses is bad, even if is it only field nailing...turns out that for cyclic loading, one of the possible failure modes is "out of plane" sheet buckling.
This is esp a problem with thin sheathing, even a few missed field nails (since they're only 12" oc) w/ 3/8 ply will allow the sheet to buckle. This buckling action actually pulls the boundary nails (that's why those wimpy .113 nails aren't so good) & compromises the overall strength. This doesn't seem happen with 1/2 (15/32) plywood. The field nails closest to the sheet corners are the most important.
That's why, I really don't like 3/8 but the code drives shea rwalls to 3/8 since it gives your best plf per $. Additionally field nailing should be more like 8 o/c not 12"
Slight over nailing allows for occasional miss
btw never used a screw gun w/ auto feed.....don't the cowboys miss with those as well?
cheers Bob
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Bobk207 wrote:

Sure, but there's more feedback driving screws than shooting nails so they're more likely to discover their error and compensate.
R
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Tear along the perforations, and mail in for your liability settlement.
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Dan-
You said the owner wanted to "would over build", wanted to exceed any & all codes.
but............

expensive, (material/labor) to build the walls on a slab and fasten diagonal shear metal banding (interior/exterior?) with screws then to cut/ install diagonal 2x6 shear bracing into the walls. <<<<<<<<
I've got news for you & him...... a metal brace will be much less stiff & probably much less strong than a 1x6 let in brace and WAY less strong / stiff than OSB or plywood sheathing.
btw a let-in brace is actually pretty quick to install
besides I thought you said you didn't have much timber experience but you're telling what's "faster"?

walls on a slab and fasten diagonal shear metal banding (interior/exterior?) with screws then to cut/installdiagonal 2x6 shear bracing into the walls.<<<<<
Those Simpson diagonal straps suck, they're easy to install but hard to get tight.
Plywood / OSB are the way to go.
If this design / build project continues in the direction its headed........

Simpson style straps are way down the list when it comes to performance. Sheathing as thin as 3/8 will be SO much stronger. If you want that place to "meet or exceed any codes", it's gonna need a structural skin; its just physics
Seems like the owner has his own ideas about what's faster / stronger / cheaper and doesn't want to be confused with the facts.
cheers Bob
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Now that's a STRONG POSSIBILITY!
Irrespective of all the suggetsions & controversy, I do know this guy will eventually do everything right. I also know he'll wind up overbuilding. He's engaged in the Nuclear industry where safety factors (4:1 minimum) run way past what the world lives by...............
Dan
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Yeah, he'll wind up overbuilding from HIS point of view......... I really don't care if he's from the nuke industry....this ain't the nuke industry, he has his own set of experience but it doesn't have much to do with timber framing.

based on what? divine intervention? He is probably the most dangerous kind of owner builder.....he thinks he knows better but he doesn't.
My first first career was aerospace / defense, weapons systems, FEM, computer programing, analysis & design.
My second career was in civil / structural research..... It took me YEARS to learn the ins & outs of a new field even though it was still "engineering"
Do I know how shearwalls behave under cyclic testing...yes
Do I know the fastest / best way to build a house.....no, that's why I defer to the experience of those who do.
Your friend may know all sorts of nuke stuff but building this garage is something different and his desire to deviate from "normal practice" could be a recipe for disaster.
When I have a "non-standard" concept that I think MIGHT be a good idea, I have at least a half dozen practicing CE/SE's / Phd's I can bounce the idea off. They can tell me whether or not its a good idea BEFORE I get into trouble.
Timber framing has evolved over the years & it's pretty good now. Could it be better? Definitely but deviating from standard practice based on a gut feeling from a totally different field doesn't sound like a great idea.
How can he have safety factors of 4 when he doesn't even know the loads? One of your earlier posts, no wind....a design wind speed of "zero"?!
Tell him to stop over thinking the garage.......just put OSB or plywood sheathing on it & forget about anything exotic.
Good luck
Cheers Bob
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Exactly, or if you want to do something exotic, get qualified people to do it for you.
It seems like 75% of the posts here are, "I want to do something everyone tells me I shouldn't, but is cheaper and probably illegal. Can one of you internet experts tell me it's OK, so I can go ahead and do what I'm going to do anyway?"
--


MichaelB
www.michaelbulatovich.ca
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