Will the Ceiling Collapse?

[teejk]

teejk-
Totally disagree with you. I was in the business from 1976 to 2001. I ran a lumberyard and designed and sold hundreds of buildings- residential, agricultural, and light commercial. ALL trusses are specific as to the load ratings of top chord liveload (snow, wind) and dead load (roof framing and roofing materials), and bottom chord deadload (the weight of the trusses themselves and required bracing) and ceiling load (the weight of the ceiling framing, ceiling material, and insulation). Trusses ARE "designed on a project by project basis".They are produced in a factory, but they are NOT "mass produced", and NOT one size fits/does all! And also, NONE are "way over-engineered to handle drop weight" (whatever that is). The manufacturers have to keep costs to minimum to be competetive. Chords, truss plate types, and the webbing all vary in sizes and placement locations, depending on the loading and spacing specifications.
There are minumums for different applications- residential carries a minimum load rating for that use, whereas agricultural and non-inhabited buildings can be specified as to the load options as the buyer requests (within reason, but canl be below residential minumums). They can be ordered with either an agricultural or residential top chord loading, and can be ordered with a ceiling load or not. People don't have to order trusses that have a 15lb ceiling load to use on an outbuilding used for cold storage or livestock shelter. Wasted money if you don't need it.
His 2x4 nailers have a weight, fiberglass insulation has a weight, sheetrock DEFINATELY has SERIOUS weight. It all adds up.
The poster would be wise to consult a truss supplier to find out if these trusses were designed for that much weight. He may be in for a nasty surprise when he has to call his insurance agent when it snows heavily and the roof caves.
He may get by, and he may not, depends on mother nature. Of nothing else, forget the rolls of fiberglass and sheetrock/drywall (even the thinner stuff, which will sag in that application anyway). He could get by with 2x4 ceiling girts 4 to 6 feet apart, use steel liner panel for the ceiling, screwed to the girts, and blow fiberglass on top of that. It would be cheaper and lighter, and would require be easier to apply, as well as no maintenance. This is all contingent on whether the trusses will handle it. He's in a heavy snow load area, and those trusses may be maxed out for that area.
Not trying to be objectionable, just trying to help.

Sorry if I offended you...I perhaps oversimplified the truss process. what I meant to say was that "pole-barns" will have a standard truss taking into account width, over-hang, spacing, roof pitch and snow load. Since our multiple contractors around here know about snow load and generally do a 4/12 pitch and generally deal with an 18" or a 24" overhang, when it comes to truss construction they call it in and the truss plant builds them from existing plans (all engineered of course). In that respect they are truly a mass produced truss...I've ordered in the morning and they are available the next morning.

I got to see a truss plant in operation once...biggest layout table I have ever seen. But at the time I was amazed at how simple the process was once they knew the dimensions...as I recall it was mostly a radial arm saw cutting operation and the layout lines were marked on the table before the press set the gangnail plate. That was years ago and I'm sure CAD has a much bigger part to minimize waste.

Now I am speaking solely about the typical pole barn which is what we are talking about here. It sounds like the building is already in place. I'm sure the trusses were designed to handle "hanging weight" of 5/8" drywall (sorry I offended by saying "drop weight") but he can certainly verify with his truss maker.

[teejk]

Do you have any links for the material you used? Prices? Store? I like that idea.
When you say "poly above" are you referring to a vapor barrier? between the steel and insulation?

Poly is just HD poly sheeting stapled to the bottom of the trusses before the ceiling material gets attached. The problem with steel ceiling is condensation might lead to rust (although I doubt it anymore...the coatings are much improved). Regardless of your choice of ceiling material I would do that anyway if you have a steel roof (I've heard about "rain" in the shop from when moist air hits the underside). Cheap if you do it now. Just google "steel siding" and poke around (you'll notice Menards is listed there). As noted above, my builder used standard building steel on the ceiling rather than what they call "liner" steel. It's more rigid and is only attached to the 8'OC trusses.

[oldbones]

Sorry if I offended you...I perhaps oversimplified the truss process. what I meant to say was that "pole-barns" will have a standard truss taking into account width, over-hang, spacing, roof pitch and snow load. Since our multiple contractors around here know about snow load and generally do a 4/12 pitch and generally deal with an 18" or a 24" overhang, when it comes to truss construction they call it in and the truss plant builds them from existing plans (all engineered of course). In that respect they are truly a mass produced truss...I've ordered in the morning and they are available the next morning.

I got to see a truss plant in operation once...biggest layout table I have ever seen. But at the time I was amazed at how simple the process was once they knew the dimensions...as I recall it was mostly a radial arm saw cutting operation and the layout lines were marked on the table before the press set the gangnail plate. That was years ago and I'm sure CAD has a much bigger part to minimize waste.

Now I am speaking solely about the typical pole barn which is what we are talking about here. It sounds like the building is already in place. I'm sure the trusses were designed to handle "hanging weight" of 5/8" drywall (sorry I offended by saying "drop weight") but he can certainly verify with his truss maker.

teejk-
You did not offend me in any way.
It didn't sound like the original poster has much experience with construction, and, to equate it to the mechanical world, if you don't understand engines, it's best to get yourself informed before you try to overhaul one.
If the original poster wants to give it a go, and is comfortable with it, then go for it. I was just giving a cautionary opinion.
By the way, there are ways to beef up older trusses so they will safely handle additional loads using "strong-back beams" in the attic area or laminating plywood to the trusses, but it's a case by case thing, and the original poster seems to be on a pretty slim budget.
As I said above, no offense taken, nor was any intended.

[/pine]

teejk-
You did not offend me in any way.
It didn't sound like the original poster has much experience with construction, and, to equate it to the mechanical world, if you don't understand engines, it's best to get yourself informed before you try to overhaul one.
If the original poster wants to give it a go, and is comfortable with it, then go for it. I was just giving a cautionary opinion.
By the way, there are ways to beef up older trusses so they will safely handle additional loads using "strong-back beams" in the attic area or laminating plywood to the trusses, but it's a case by case thing, and the original poster seems to be on a pretty slim budget.
As I said above, no offense taken, nor was any intended.

Engineered trusses should not be altered in any way...this includes even drilling a hole in one (or adding additional bearing etc.) of the chords etc... granted adding deadload to one that was designed to carry said deadload is fine but altering a truss in any way voids any liability claims against the seller, manufacturer or the engineer...

[BHD]

as stated before I would not use dry wall, and would if used dry wall on 24 OC joist it would be 5/8 but I would not want to load the roof with that much extra weight,

I would put up the building tin similar to the roof sheets,

[teejk]

teejk-
You did not offend me in any way.
It didn't sound like the original poster has much experience with construction, and, to equate it to the mechanical world, if you don't understand engines, it's best to get yourself informed before you try to overhaul one.
If the original poster wants to give it a go, and is comfortable with it, then go for it. I was just giving a cautionary opinion.
By the way, there are ways to beef up older trusses so they will safely handle additional loads using "strong-back beams" in the attic area or laminating plywood to the trusses, but it's a case by case thing, and the original poster seems to be on a pretty slim budget.
As I said above, no offense taken, nor was any intended.

I owe an apology for what was a very "snarky" post on my part...waiting for paint to dry gave me a chance to "poke around". There are hundreds of pages of material on the internet discussing this very topic. As usual, when I "assume" I have a 50/50 shot at best. In my case I assumed that any truss would be designed to handle 5/8" rock "hanging load" on the bottom (something I read a long time ago).

Sounds like that is true in residential construction but in a pole building it sounds like the trusses can be ordered "with or without" ceiling. Given that even around here outbuildings are not subject to sign-off, a call to the truss mfgr or a structural engineer might be prudent. Steel is relatively light compared to rock (my builder carried 3 24' sheets per trip if it means anything). As mentioned above, standard gauge was used in my shop in lieu of the lighter stuff (a few more $$$ but in the whole vast scheme of things was "spit").

I might say that in farm country I would at least get some prices from people that do it for a living. They have the tools (cutting along the length is a real PITA without a "nibbler") and experience (moving the stuff without messing up and creasing it) and have wholesale sources for materials (metal and Jchannel). Since we will soon be in "mud season", they might cut a good deal on the work. And he'll save on bandaids!

[Dr Dave]

Find out the specs for your truss's. I priced a building with Cleary, and the first thing, he asked, would it be insulated? Then we went from 9' post spacing to 8' and said this would require a different truss also. He said, that most buildings are not designed to add a ceiling and insulation, if not speced that way.

Dave

[teejk]

Find out the specs for your truss's. I priced a building with Cleary, and the first thing, he asked, would it be insulated? Then we went from 9' post spacing to 8' and said this would require a different truss also. He said, that most buildings are not designed to add a ceiling and insulation, if not speced that way.

Dave

I already beat myself up above Dave...most of us hire out that construction (as they should...a friend tried the DIY a few years ago and broke his back coming off the roof steel in a light mist) and just assume that the contractor knows what to do. Looking at it though I find it hard to believe the cost difference on a truss is that much so why not just spec them that way? This discussion leads me to wonder what I have in my building!

[BHD]

actually there is a very easy way to cut most roofing tin that is used on modern farm buildings, and that is with a utility knife, score a deep line and then fold the tin and it will snap at the scored line, (it may take a few passes, to get a deep score). (will not work on the old Strongbarn tin)
my SIL does tin roofs and buildings and cut the long way most of the time,

here is another person description on how to do it, Viewing a thread - roofing metal cut?

[andrec999]

If you go with the foam insulation sheets, check with your insurance company before. Here, they will not insured an unprotected wall or roof , foam insulalion or foam sprayed insulation must be covered by a minimum of 1/2'' sheetrock . For obvious fire and liability reason.