H-beam studs
Another hair-brained idea came to me. Disregarding the extra dollar/stud and the labor involved, if a person took 3-2x4s and made then into H-beams as replacements for 2×6 studs, would they support as much weight as a 2×6? It seems they would be superior in both directions. These studs would have 1/2 plywood on one side and 5/8″ sheet rock on the other. My reasoning for this madness is that this gives a 3.5 “catch area” for sheathing, avoiding sheathing being nailed at the edge.With nails back from the edge, it seems the sheathing would be stronger and you’d never have that odd instance where the nails or sheet rock screws barely catch the edge of the sheathing, looking rather useless structurally. This would generate some other, labor-costing issues, too, but let’s ignore all that for now. Structurally superior to a 2×6? thanks. klingel
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john, the sheathings make an H out of studs already.
AJ: Yes. True, but I am looking at replacing the studs. Thanks. j
John,
Three 2x4s is overkill and a waste of lumber.
You could always switch to using I-joist material for studs if you want, like Katrin Klingenberg advocates. These usually have OSB webs, though, and some people don't like OSB.
Structurally stronger - theoretically it would be but it would probably not fly in seismic areas without massive testing or engineering calcs. Seriously, look at the I-Joist method with wider flanges. Of course I am curious about which way this H system ot you faces ][ (one leaves two gaps hard to fill while the other one is 6 1/2" wide and possibly more thermal transfer than a regular stud)
If I am reading between the lines properly, I think the underlying issue you are dealing with is drywall & sheathing issues. First, per the manufacturers instructions, the drywall should actually not be butted together on the joists or studs, but inbetween two joists with a backer plate (1/2" plywood works, or they have special ones for purchase) As for the exterior sheathing - by properly caring for materials to be installed, leaving the proper spacing for expansion & contraction, followed by protecting it properly as soon as possible will help eliminate any edge swell or other issues
Not "theoretically" stronger, but actually so. It would have almost double the compressive strength parallel with grain, 3.6x the lateral buckling resistance, and 4x the resistance to wind deflection. There would be no issue about using such an H-stud in a seismic zone, but it uses almost twice the volume of wood as nominal 2x6 studs and considerably more labor investment.
There would be a little more thermal bridging because of the 3D heat transfer paths
No DW manufacturer requires butt blocks, that's an aftermarket option for invisible butt joints.
John's issue wasn't edge swelling but fastener concentration at meeting panel joints. CA codes require that all exterior shear panels meet at a nominal 3x framing member to avoid wood splitting or weakening from tightly-spaced fasteners. You can accomplish the same thing by doubling the studs every four feet, but outside of extreme seismic zones that's not necessary.
Great. Thank you all for the information. I realize the volume of wood used would be double a 2x6, but the price is only $6 vs $5. Labor is free. •Sean: The flanges of the H-beam would be parallel to the sheathing, with the web then in the normal position of a stud..• The easiest and cheapest solution is of course to double the studs every 4' as mentioned, but then you'd have to do that more frequently so you could stagger joints; maybe staggering joints is not an issue in a wall???? If not, then a double stud is the answer. BTW: This system (no H-beam, just normal studding) of sheet rock, 2x6, plywood, insulation, then 2x4 w/ cladding, all filled w/ DPC, is not my idea; it is Thorsten Chlupp's. I was just thinking about the edge tearing/minimal catch area problems that at least I run into. Thanks again. j
That problem is pretty much eliminated by using rough-sawn 2" thick lumber.
On the west coast in seismic zones, builders sometimes use 3x6 studs every 4'-0" so that plywood joints fall on a wider (2.5") stud face, to get the nails further from the panel edges. Engineers will specify this practice when the lateral loads require a lot of perimeter nails (sometimes 2" on center 8d nails).
Robert: You are spoiled w/ your hemlock. I don't think our spruce will stay straight. Maybe I could import about 100 studs???
TJ: That is good to know. That is one of my worries when the stud spacing is just a tad off. I'll have to see if 3x6 is available here; never have looked for it, and it may be cheaper than two, 2x6. j
Just read the 2010 NYS codes for an hour today... There is wording in it that allows rough sawn lumber with out a lot of hassle. I never saw that prior and am very happy to see it now.
I would be concerned with the stability of an H stud, but you would be fine if it were an I stud.
Seriously, hard to ignore labor costs, rarely are they not an issue but if such a strategy were to make sense including labor costs, what would you do at windows, corners, etc. Seems like a lot of work for not much benefit, but I guess you would get an extra 1.5" of wall thinkness thus more insulation. Interesting idea - if we had the choice of a 1/2" or 1" thermal break (rigid foam) vs an extra 1.5" of insulation - which would you choose.
Dan K: Windows and doors would take some tweaking, and likely the easiest would be to use normal studs there. Dunno; I am not that far into this thinking yet. If this were a "normal" (whatever that means) double wall system, I think T's 4' OC would be ideal, on both the interior and exterior wall. It would mean an extra 2x4 every 4', but it would eliminate a problem I don't like. The labor is there, no question, and this is surely not an option commercially. It would mean making about 50 of these things, but since I get paid 60 minutes/hr, plus lunch, it won't cost much more for me. That is an interesting question about which option to chose; I don't know enough to decide. BTW: This whole mess (H beam) would be surrounded on the outside by 6" of DPC and have DPC w/in it, so it would introduce more wood and reduce the overall wall R value a tad; not ideal. Things to think over.