help with tractor roof

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I have to build a roof to get the tractor and trailer undercover and need advice. It will be an add-on to a 32x42x14ft pole barn, so one side is already built lol.It'd be an open roof 30ft long by 22ft wide that worries me so do you think it can be strong enough with my materials onhand? Built to local code would be nice but only safety is necessary. The highest recorded wind here was 82mph over the treetops, it was about 40mph at groundlevel.The thirty feet of used shopwall there has four 6x6 posts in 4ft of concrete, a good commercial build. The ledgerboard for the new roof will be at the 12ft high mark on the 14ft eaves. (The shop is doubletrussed inside.)  The outside posts would be 10ft above groundlevel, to make a 2ft downgrade on the new roof over its 22ft-wide-span.Are these materials good enough or do i have to start drinking water to save $$ ?- 2" Sked 80 blacksteel pipe for outside supports. Pipes spaced 6ft apart bolted onto concrete footings poured 3ft deep.- 2" Sked 80 pipe welded across the tops of those vertical poles.- 2" Sked 80 pipe rafters spaced 3ft apart to lay 29ga steel roof panels on. (Laid out level on top of two bricks with my foot on them the pipes bow about three inches.)-  5/8" hardsteel hotdipped bolts.-This wall is an another possible tractor roof loc, but support posts can't go in the middle of the drive. Can a bigger 12ft-wide replacement awning be cantilevered off the shop wall? There are three 6x6 posts in the wall to anchor to. Prolly not.Century Minnesota 230v AC Stick and MiG 70a welders. Not enuf spare steel.
Reply:I'm not sure Schedule 80 is structural or it's loading strength. I would check that first before putting a few hundred pounds of metal on top...maybe even a few thousand, depending on how large the roof is and the per foot weight of SCH.80. It may not stand up to the severe loads of wind, snow or both.John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:First off, if there are codes to follow or adhere to or even if they are just there for guidance, then follow them.Next, if the barn had 6x6 posts anchored to 4 feet deep of concrete, then I'd probably say to anchor your awning posts to 4 feet deep of concrete too.Next, I really don't think 2 inch pipe is big enough to span 22 or 30 feet.  You got 3 inches of sag with just your foot on the middle of one pipe!So, your proposed awning is 30 feet long and goes out from the existing barn 22 feet, right?  And you want to just run 2 inch pipe clear-span across 30 feet?  And then run 22 foot long (actually 22.1 feet long with that slight roof slope) 2 inch pipe 'rafers' ?  And the whole thing sitting on 5+5 2 inch posts?Nope, not a good plan.  To clear-span 30 feet, you are looking more at 10x10x1/4 steel tube not some dinky 2 inch pipe.  And even with 10x10x1/4 steel, you are looking at around 2 inches of sag in the middle (with the roof panels on and you or a buddy or something else hanging from the middle of the span).
Reply:I do a fair amount of building work, and there are soooo many different ways of skinning this cat I can't even start to list them all, but I agree 2" sch80 is not gonna be a wise choice for what you are trying to do.  If I am reading you right the roof will hang out 22ft from the existing building.  To span a 30' outer edge I personally would go with atleast three 4"sch40 pipe or square tubes as columns for support, (basically two 15ft bays looking at the 30ft side) and then frame it with say 6" channel up top with 6 inch "Z" perlings  between them to every three feet to screw your roof metal to.  as i said this is just what (I) would do.    There are lots of variables you can change and still have a solid building. good luck and keep us posted on how it comes out.  ~JacksonI'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:Originally Posted by MicroZoneI'm not sure...
Reply:Clear-span side-to-side of 20 feet makes your material needs -much- smaller, but 4x4x1/4 is still going to be a bit to small to span across 20 feet.  Especially with a snow load!  Snow can be #$%i*@# heavy !  Clear-span 20 feet looks more reasonable with 4 or 5 6x6x1/4 tubes.If you can run center posts at the 10 foot mark, and you run 4 or 5 4x4x1/4 beams across the 20 foot span supported at both ends and the middle (making two 10 foot wide x 22 foot deep 'bays'), you are good IMHO.  If you can run mid-posts at the 10 foot marks, you should be good with the 4 or 5 4x4x1/4 beams for the 30 foot span supported at both ends and two mid-posts at 10 and 20 feet (making three 10 foot wide x 22 foot deep bays), IMHO.Let's see if this CAD (Crude ASCII Drawing) comes through.  This is a top view, each x is a post and the across "-" are the 4x4x1/4 tube beams.  Side-to-side you are 20 feet and coming out from the existing wall you are 22 feet, so you have two bays 10 feet wide x 22 feet deep coming out from the shop/barn wall.(existing shop/barn wall)x----------x----------x....x----------x----------x....x----------x----------x....x----------x----------x....x----------x----------xIf you want to go 30 feet across, add another bay and get three 10 foot wide x 22 foot deep bays.(existing shop/barn wall)x----------x----------x----------x....x----------x----------x----------x....x----------x----------x----------x....x----------x----------x----------x....x----------x----------x----------xOr running 30 feet across and running 4 4x4x1/4 beams with end supports and one row of mid supports at the 10 foot mark, to give you one 10x22 bay and one 20x22 bay should work.(existing shop/barn wall)x----------x---------------------x.......x----------x---------------------x.......x----------x---------------------x......x----------x---------------------xYour z-purlins then all go in the 22-foot direction and get spaced 3 feet apart and have to span across 4-7 feet or so depending on if you go with 4 or 5 beams.  But then your corrugated metal roofing is going cross-wise across the z-purlins???Oh, and I'd probably run extra posts on the awning wall closest to the shop/barn and then attach that top to the ledger on the shop/barn wall as well.  Remember to flash the joint from the shop/barn wall so water doesn't run down the ledger or seam but runs down the awning roof instead.Last edited by MoonRise; 06-15-2007 at 04:05 PM.
Reply:Thanks for taking the time to make those drawings and discuss the materials.You must get a lot of snow there. Here on the flatlands in Puget Sound we get a few inches a year. Island county code for live snow load is 25 pounds per square foot at elevations below 500 feet above sea level (the whole island.)Ok, if needed then posts under the ledgerboard too. Center posts between the outside posts of the new roof and the shop wall are a PITA for backing trailers in and out through to the far side but i won't afford the type of structure to clearspan 22 feet, so.Yes one way of constructing it would leave the roofing panels crosswise of the rainwater flow, req silicon sealer at each roof panel seam and probably causing future leak problems. Don't care about standing water in the corrugation, everything here is wet dam near year round anyway.I like your drawing, I'll post my own because it's prettier.looking down at the roof:_______________________________________._____Door_  _____.___._______Door______.__|.................................................  ..................................................  .........................................||.................................................  ..................................................  .........................................||.................................................  ..................................................  .........................................||.................................................  ..................................................  .........................................||.................................................  ...Shop 32'W x 42'L x 14' Eaves.............................................  ||.................................................  ..................................................  .........................................||.................................................  ..................................................  .........................................||.................................................  ..................................................  .........................................||.................................................  ..................................................  .........................................||_________________________________________________  _________._____Door ______.__|!P#####################P#######################P!!##############################################!!##############################################!!##############################################!P###############P##############P###############P!!################# Roof 22'W x 30'L.##################!!#########(20'Long only if I can't get a 30' eave strut)##########!!##############################################!P#=#=#=#10'#=#=#=P#=#=#=#10'=#=#=P#=#=#=#10'#=#=#=  PP is Posts# is new roofing.=#= is Eave Strut and roofing.It'll take a couple of weeks to round up materials. Interesting that a steel company near here wants $5.33 per foot of the Z-purlins, while a steel company in Pennsylvania wants just $2.00 per foot. The punch line is freight cost o'course.Last edited by RexB; 06-16-2007 at 04:06 AM.Century Minnesota 230v AC Stick and MiG 70a welders. Not enuf spare steel.
Reply:My quick calcs -were- done with a 25 lb/ft2 for snow loads!  25 lb/ft2 over that roof is 16,500 lbs for the 22x30 roof size!!!!  Using 4 4x4x1/4 beams spanning 20 or 30 feet with mid-span posts at every 10 feet was OK, without the mid-span posts No Way!A quick calc using 4 4x4x1/4 beams 30 feet across and supported at the ends (obviously) and at one mid-span point at the 15 ft halfway point looks OK.  That gives you two 15 wide x 22 deep bays.If you want the corrogated roofing to run in the 22 ft direction (what you really want IMHO, so that the rain can just run down the corrogations), then you need another layer of steel structure.  If the beams go side-side (the 20 or 30 ft direction), then you cross the next layer of steel (purlins?) in the 22 ft direction, then the next layer goes side-to-side (the 20 or 30 ft direction), and then the sheet steel roofing can go on with the corrogations running in the 22 ft direction.If you are trying to run the beams in the 22 ft direction, then you'll -have- to put support posts underneath them, and your spacing between them will be limited to what the purlins can span and to having enough beams to hold up the roof snow 25 lb/ft2 load.  Clear-spanning 20 or 22 ft with 4x4x1/4 steel won't really do, you'd have to go with something like 3 6x6x5/16 beams.  That would give you one big bay that you could pull the tractor into parallel to the existing shop wall -IF- the purlins can span 10 or 15 feet (depending on if you go with a 20 or 30 ft length).CAD (Crude ASCII Drawing) top view again:x..................x...................x|..................|...................||..................|...................||..................|...................||..................|...................||..................|...................||..................|...................||..................|...................||..................|...................||..................|...................||..................|...................||..................|...................||..................|...................|x..................x...................xx = vertical posts| = your 6x6x5/16 beams running 22.1 feet long. = purlins and/or dummy drawing spacer so forum shows the CAD semi-correctNote: this advise worth what you paid for it, not responsible for objects being bigger in mirror than they appear, general disclaimer, etc, etc.
Reply:Those 22'x30' structure(s) look good and strong thanks. Posts spaced down the middle. The materials price quotes around here are about $3,100 some of it delivered. Have that by the end of summer.Last edited by RexB; 06-20-2007 at 09:47 AM.Century Minnesota 230v AC Stick and MiG 70a welders. Not enuf spare steel.