This may have been part of the story for me as well. I told the town I had no immediate plans to heat, which is true. Down the road I’d love to heat it, but maybe that’s why my 2x4 construction plans were ok today.
Sounds like you got away with one…anything taller than 10’ without lateral support is supposed to be analyzed at a minimum. Given your 32’ clear span, no heat+snow load I think you would easily be in 2x6 range if not more with 24oc spacing.
Will it fall down? No. But a heavy snow and 60mph wind gust is going to make you think it will.
Lateral support of what type?
Any type…you currently have lateral support at the slab- assuming it is bolted down, at the roof and at the corners…that meets the prescriptive code at 10’ or less…but at 12 you should have had to submit calculations
No calculations required, different towns have different requirements. There are going to be 1000 inspections along the way though, so if something falls short, they should tell me immediately. At least that’s what the town said…
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…and yes, bolted down to the slab. 12-1/2" anchors sunk into the concrete, 3 more drilled in after the slab cured, 25 tap-cons after walls went up.
The calc thing is nys building code not local ordinance
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It isn’t surprising they didn’t catch it…many small town code offices aren’t very sophisticated and often depend on their knowledge of old BOCA codes and outdated rules of thumb…I just would keep quiet about it during inspections…otherwise you’ll have to do some math at least and add studs at worse
Code for any type of building?
Roof loading which is your primary load here is basically the same for all building types because it is driven by snow load
So there is no distinction between attached or detached structures? I assumed there was, not that I kenw what that difference would even be.
I think it is important to note that when I had the complete job quoted other places snow and wind loads were part of the quoting process, and I remember a good majority of them had truss spacing at 24" o/c, which the trusses sit over the studs, correct? Many of them (not all) quoted 2x4 studs. Doesn’t make it right of course…
I don’t believe the code prescribes specific lumber dimensions to be used in one type of building or another…typically other requirements like live loads dead loads or thermal performance drive the minimum sizes
Most houses are 2x6 these days because of insulation not structural loads
Makes sense
Truss design and spacing is a different creature. Those elements are engineered and when you think about it their effective cross section that is carrying the load is much bigger than the cross section of a single 2x4. Think for a second if you were to lay a 32’ long 2x4…hell even a 2x12 over that same 32’ span it would not even come close to carrying the roof loads due to the long span.
In some cases you do need to align trusses with studs below but part of the reason for a double top plate is to minimize this requirement. In very cheap construction they will use a single top plate but that requires the floor or roof stricture to align with the studs below because the top plate would not be able to handle the point loading from the roof or floor joist
I would still suspect that most quotes were using 2x4 at 16oc which might be why you thought they would be high compared to your number…that is 33% more studs you have to buy compared to 24oc
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Again not trying to scare you…it’s not falling over…but I think it is marginal at best code wise…structural codes have tons of safety factors built into it so there is a good bit of flexibility
Local building codes supercede state but must be at least to the state requirement. 2 x 4 will be fine but that’s why I suggested gluing at least the corner sheets to provide lateral stability for wind load. I don’t believe NYS enrrgy codes apply to structures with non permanent heat and classified as non habitable space. You can still get projects to pass with 2 x 4 walls as the structure is calculated as a whole, including the furnace efficiency rating. Energy codes are becoming more strict every day. 3/8" out of square is more than fine. Dealt with worse. Just take your time and understand your layout. Use H clips between trusses even if using plywood.
i don’t really see the benefit of gluing the plywood at the corners…the corner isn’t going to be your weakest point in this setup…the point of concern is going to be somewhere out near the center of the wall face where your forces are going to be greatest. probably the most beneficial thing you could do to improve this wall assembly would be to place horizontal blocking at 4’ oc. vertically so that all edges of your plywood sheathing are continuously nailed to something…especially given the 24" oc spacing.
when a wall like this starts to fail usually the first thing to happen is the horizontal edges of the plywood start to pop out…and since each sheet in this setup would only have 5 nails along its long edge with a wall section with a tendency to bend and bow you would do a lot to strengthen it by adding blocking behind the horizontal joints and nailing those edges every 8" or so…you would nearly double your nails which would counteract the ability for the plywood to pull away along that edge.
you could also install the plywood vertically although since your wall is taller than a typical sheet of plywood you would end up with the same edge condition problem just fewer of them…things to think about.
i also wouldn’t waste my time with hurricane style twist anchors…they aren’t going to benefit you as they really are only intended to resist uplift…you’d be better off looking through the simpson connection catalog for an appropriate connector for your truss style that typically also provide a good deal of uplift bracing even if they are not florida product approved…
Since the attachment of the plywood is what creates a wall “system” it is the fasteners and the density / strength of the materials and fasteners that give it rigidity and resistance to forces generated by wind loads. Adhesive on all sheets would be the best but I’m trying to be realistic. The contact area of adhesive would far exceed the strength offered by additional fasteners.
The Simpson fastenets are I believe LZ28’s which are quite strong enough and easy to install. An engineer would typically select a connector but I’ve used these in the past and seem to work the best. They are a design code requirement and simply toe nailing a truss is neither safe nor acceptable.
Just my 2cents.
i think in terms of bang for your buck you are going to get more out of putting in the horizontal blocking and nailing all edges with horizontally oriented sheathing…just gluing it isn’t going to change the fact that you only have 5 points of connection along the critical edge of the sheathing and you have to put the nails in anyway…not to mention that you would probably end up spending $300 on adhesive to glue up every sheet on a building of this size.
Again, just suggesting adhesive on certain locations. The sheet stock is what provides the strength but it is in relation to how much of the framing member is attached to the sheet good. How much better could you get than 100% vs. a fastener. If you wanted to win the strongest construction contest, you’d glue them all but that’s not realistic. The mid height blocking actually adds little strength to the wall. The joining of the two materials is where the strength is created.
the blocking isn’t what is really adding the strength…it is just there to give you something to nail the horizontal edge of the sheathing to.
if we were to simplify the situation to an 8’ tall wall, in order to have the strongest wall section you would orient your plywood vertically because you would then have continuous nailing along all edges with no unsupported joints.
if you were to install the plywood horizontally the long edge would only get a nail ever 24" instead of 6" or 8". so when the wall is loaded from above the vertically oriented sheathing wall would far out perform the horizontally oriented wall since it would be susceptible at the horizontal joint which would align with the maximum shear stresses. those stresses would only be being resisted every 24" instead of 6 or 8. the horizontally oriented wall could be made to perform basically the same through the addition of horizontal blocking to allow for the long edge to be continuously nailed.
May I inquire as to your profession?
architect