New Shop Build Roof Question

[Breakineven]

can someone explain to me what this means? Guess I am trying to order insulation supplies….


Trusses: Clear span factory engineered to 4’ OC., 4/12 pitch, 42-5-5 snow loading
-Purlins/Bracing: 1 row of 2x8 treated bottom purlins, 2x4 wall purlins, single 2x6 top ribbon, 2x4 roof purlins, 2x6 fascia backers
-Steel/Trims: 29 Ga. Colorfast steel-roof and walls, deluxe trim and sealant package, all steel is fastened with screws, 48” wainscot on one sidewall with the OH doors, steel ridge cap, roof overhang:

 

[Wrench97]

I have yet to see 4' on center roofs not sag after a snow load or two.
4/12 pitch is a 4" drop for every 12".
42-5-5 should be 42 lbs per square foot live load, 5 on the top cord and 5 on the bottom cord of the truss.

 

[Bert_]

I have yet to see 4' on center roofs not sag after a snow load or two.
4/12 pitch is a 4" drop for every 12".
42-5-5 should be 42 lbs per square foot live load, 5 on the top cord and 5 on the bottom cord of the truss.

I see lots of sheds built with trusses 4 ft on center and pole buildings 8 ft on center. Never seen one sag.

 

[firebirdparts]

Well, that depends a whole lot on which way the purlins are oriented and then how big. 10 foot truss spacings can be adequately supported without a lot of material. 2 by 4's flat, if that's what they are here, does seem a little sissy. But maybe they're not flat.

To the OP, the "fascia backer" is going to be on the end of the truss where a gutter would be. Less clear to me what would be hanging on the end of the building if you specified an overhang on the end. I guess most people don't; it's a little aggravating to get that extra foot on the building.

 

[WNYflyer]

can someone explain to me what this means? Guess I am trying to order insulation supplies….


Trusses: Clear span factory engineered to 4’ OC., 4/12 pitch, 42-5-5 snow loading As already mentioned by Wrench97 most likely roof truss design loads as in 42psf top chord live load (snow), 5 psf top chord dead load, 5 psf bottom chord dead load.
-Purlins/Bracing: 1 row of 2x8 treated bottom purlins (bottom "girts" rather than "purlins" at base of wall?), 2x4 wall purlins girts? single 2x6 top ribbon/girt?, 2x4 roof purlins, 2x6 fascia backers
-Steel/Trims: 29 Ga. Colorfast steel-roof and walls, deluxe trim and sealant package, all steel is fastened with screws, 48” wainscot on one sidewall with the OH doors, steel ridge cap, roof overhang:

"Purlins" on are top of a truss and are spaced such as to properly support the roofing material for snow, live, wind loads, etc., "girts" are on the walls and spaced as such to properly support the siding material for dead loads, wind, ect.

 

[dcg9381]

can someone explain to me what this means? Guess I am trying to order insulation supplies….

Most steel buildings are offered with "insulation packages" - meaning they are wrapped in a big blanket.
What insulation are you thinking about? Because if you're doing rolls, you'll probably need additional framing or some other means to keep it up on the wall.

If you're doing foam, you really don't care and you're done in a day.