Pole barn construction

pigdoc

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Going to try something here. We'll see what the response is.

I spent 4 summers after HS, building pole barns for a national company, Wick Ag Buildings, Mazomanie, WI. These were precut packages, typically arriving in two flat-bed semi-truck loads. At the end of that time of my life, I was super-fit, and endowed with a body of knowledge that earned me a job offer of Crew Lead. Instead, I went to vet school...

Anyway, I'm going to work through the process of planning and building a typical pole barn shed, from start to finish, in a half-dozen installments. For your comment!

First installment:
Planning, layout, and pole-setting.

At Wick, all our buildings were built with 9-foot bays. This allows 10-foot purlins to be used, overlapping the ends of them for strength. At a minimum, you're going to want a large rolling door in a sidewall, or a pair of sliding doors meeting at the center of an end wall. You'll also want a walk door. Make your sliding doors as wide as you can. Twelve to eighteen feet wide is not too much. For the pole missing in the door opening, we used a 2x12 yellow pine triple header, with a stub pole sandwiched in the header span to land the truss against.

Also, it's a lot cheaper to go "up" rather than "out", so don't be bashful about sidewall height - 16 feet is good, and gives you potential for loft space. You can use "filon" (translucent fiberglass siding) for the top 3 or 4 feet of the sidewalls to let light in.

On an average shed (60x90), a 5-man crew can lay out the building and set all the poles in about 6 hours.

Once your pad is prepared, lay out the building by erecting batter boards back from each corner of the building. These give you a place to attach string lines, and adjust them as needed. On pad preparation, the less fill, the better off you are, because fresh fill is never as dense as the original surface, and pole purchase can be thus compromised. Your floor is also likely to settle over time if it's built on top of fresh fill.

First thing is to get the string lines representing the building perimeter squared up. Measure the diagonals and keep adjusting string lines until the pairs of diagonals, widths, and lengths are all identical. Now, from a corner, measure your 9-foot spacing for the poles and use a Sharpie to mark the CL of each pole on the string. We used small squares of cardboard held in place on the ground with a nail at the center point of each pole. These are your targets for the auger point.

After drilling your holes, start setting poles at the corners. You want to nail a scrap block of 2-by on each outer face of the corner poles and set the outer face of that block right on the string line. When digging holes and preparing poles, some of the best things you can do are:
- Drill your holes plumb. Not as simple as it sounds, because an auger on a three-point hitch will tend to move in an arc as it goes down. When drilling, just move the tractor forward a few inches a couple times as the auger goes down.
- Place a concrete "cookie" in the bottom of each hole to set the pole on. These will greatly resist settling of the poles.
- Before setting poles, nail "cheek blocks" on two opposite sides of each pole, near the bottom. Use some stout treated lumber for cheek blocks and nail them on with 20D ring shank nails. These will improve the ability of the pole to resist pulling out of the hole (wind) after the shed is built.
- Just before backfilling your poles, dump a bag of concrete mix down the hole. Just dump it in dry. It will absorb moisture from the soil and cure on its own.
- When tamping poles, tamp the bottoms thoroughly. Because, it is critical to secure the bottom of the pole in position. A little bit of dirt, tamp it tight, a little more dirt, tamp it tight. And on. If you don't do that, and the pole leans over, the bottom of the pole will move laterally, screwing up your pole placement.
-After the corner poles are set, on each of them, drop 4 braces from head height to the ground to brace the pole plumb until it's framed in.
- When you set the rest of the poles (the poles between the corners), remember to set them back 1.5" from the string line. [Safer, for a straight wall, to NOT try to set your poles right on the string line.]

[Back in The Day, our poles were treated with pentachlorophenol which was finally "cancelled" by EPA in 2022.] We used rough-cut (full 6") treated yellow pine poles.

Typically, poles with inferior treatment will rot off right at ground level. If I'm not confident in the treatment, I will soak the poles thoroughly with used motor oil near ground level after they are set. I've also gone to the extreme of wrapping untreated poles in roofing felt before setting them.

Next installment - girting up, finishing framing in readiness for trusses. Typically, for our crew, Day 2 was for swinging trusses.

-Paul
 
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Daferris

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One of the companies around here in Michigan uses concrete poles till they are about 3-4' up out of the ground the wood past that. Also do the final grade so water runs away form the poles and have gutters and downspouts or at least a 2' overhang so the rain water does not collect next to the poles.
 
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North Idaho Wolfman

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New pole barn builders do not use solid post any more they use glue lam posts.
 
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fried1765

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Not all of them. Solid posts are still pretty popular in these parts as they are "generally" less expensive.
My 36' x 48' Morton, built in 1984, has solid wood PT 6x6 posts.
Now 39 years old, with no apparent post rot.
Soil is pure sand, .....so is well drained.
 
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North Idaho Wolfman

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We setup one for a customer last year that became a monolithic slab with the posts set in steel post bases.
When they went to drill the holes all they hit was solid granite at about a foot.
I really like the way that turned out.
 
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pigdoc

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This installment: Framing, phase I

But, first, a bit of insider info. These large national commercial pole barn companies build the trusses and precut all the lumber and siding for the buildings they sell, and send the materials out on flatbed trucks to the jobsite. In the design process, a quota of man-hours to build that building would be established. For a straightforward 60x90 machine shed, that was about 250 hours. Five man crew, 10 hours a day, 5 days to finish the building. The crew I worked on would use, on average, about 85% of the hours quota. And, we often worked sun-up to sundown. When I was working, we were backlogged MORE than a year, so we did LOTS of OT. The foreman got the pay for the hours not used as a bonus at the end of the year, to distribute (or not) to the crew at his discretion.

At this point, you have all your posts set. Corner posts are adjusted plumb and are braced to the ground in two dimensions. Rest of the posts are braced plumb "side-to-side". You can just brace each post to its adjacent post. At this point, we're not concerned if the posts are a bit out of plumb "in-and-out".

Go to the pile of 10-foot 2x4s and pick out 4 of the straightest ones for each bay of the building. These will become your ridge purlins and eave purlins.

Next step is to set up a transit somewhere in the building's interior and shoot all the posts. A partner uses a framing square to mark a horizontal guide line on the outside surface of each post, at the transit-gazer's instruction. Then, the actual bottoms of the sidewalls are established by measuring DOWN from that guideline the same amount on each post and driving in a 20D 'perch' nail in the middle of the outside of each post, at those points. This will be the bottom edge of the bottom board.

Now, we can hang the bottom boards. We commonly used planed, treated 2x8s, with tongue-and-groove edges, resting the bottom edges on the perch nails in each post, and nailed to the posts (20D ring shank). For challenging grades, you can stack multiple boards to fill in the gaps to the grade. Stacked bottom boards adds stiffness at the bottom edge of the sidewalls and gets the siding up away from the ground (to delay rusting of the siding). Consider that multiple, stacked bottom boards also provide some protection against accidental bumps into to the sidewall from the inside of the building after it is finished. Thin steel siding is not very forgiving of those accidents!

Then, girting. We used #2 SPF 2x6s, each end nailed to each post (two 20D ring shank). You'll need to calculate the distance between each girt so that the girts are all evenly spaced ~2 to 2.5 feet apart vertically on each post. Cut a pair of girt spacers from scrap 2x4. Tack one spacer to each of two adjacent posts to rest the girt on for nailing. Move the spacers as needed to evenly space all the girts. Start with the bottom row, then stand on that to do the next row up, and so on. We always eyeballed each girt and placed it so that the bow was up.

If you're installing filon sidelights at the tops of the sidewalls, you may want to space the top girt so that it is along the bottom of the sidelight rather than across the middle of it, to maximize the light. You'll need a girt anyway at the joint between the filon panels and the steel siding. [Once your girt spacers are cut, you might want to mock up girt placement on a pole. It's easy to miscalculate the girt spacer length!]

After girting is complete, with a chainsaw, notch the tops of the posts 1-1/2" to receive the heels of the trusses. Measure up from the guidelines again to have all the truss heels landing on the same horizontal plane. Don't worry about trimming the tops of the posts at this stage, that will be done after framing is complete.

Sidebar: You want to be strategic in truss placement and which side of the post is notched. Don't put the truss heels on the door opening side of the door posts. Because, eventually, there will be diagonal braces between the truss lower chords and the sidewall posts, lapped onto the posts. You don't want that lap in the door opening. And, make sure that each of the two posts that a truss lands on is notched on the same side! DOH!

Install 2x12 SYP headers above the sliding door openings. Put the top edge of the headers on that same horizontal plane corresponding to where the truss heels will land. Orient the individual header boards so that any bow is up. Nail the headers up to secure them (20D ring shank), then through-bolt them to the posts with a couple of 1/2" bolts in each end. [Countersink the bolt heads so the siding can go over them. We always used bolts with hex heads, rather than carriage bolts so that we could put a flat washer under each bolt head.]

If you have a sliding door opening in the sidewall wider than the bay spacing (9 feet), then you'll need a stub post sandwiched between the inner and outer header boards to support that truss heel, notched to receive the truss, and through-bolted to the headers. Wider door openings call for doubling up on the headers. [That's an engineering concern that you should get consultation on.] For extremely wide door openings, we would use a steel I-beam as a header.

It's easier to put off hanging the eave purlins until after trusses are set.

At this point, phase I framing is mostly complete. For a crack crew, that's at either the end of Day 1, or mid-day on Day 2. But, there are a few more framing odds-and-ends to complete before the building is ready for siding. We always used to block the corner posts and door posts with 2x4 scrap between each girt, similar to what you do with the corners when hanging drywall. Gives a purchase to (eventually), securely nail on trim. Also, the top block on the door posts contributes to supporting the headers, so nail it securely. Vertically, to the outside surfaces of the door posts, on top of the girt faces, nail a 2x2 flush with the door opening. This will fully support the door opening trim, and give a flat surface for the inner surface of the sliding door to clamp to when closed.

Sidebar: Once the headers over the sliding door openings are up, the optimal size of the sliding doors is known. And, so, sliding door construction can start. One of our crew (Gene) was the door specialist, and would start building doors ASAP, because it took him a couple of days to finish them. That way, the doors were ready to hang about the time siding was completed. We used metal wall studs as horizontals in the sliding doors to support the siding (lighter than wood). The side, top and bottom members were of heavier steel (12 gauge?). The door rollers hang the top member, and support the entire weight of the door, so reinforcement of those attachment points is important.

You can go ahead and install diagonal bracing in the building corners (2 per corner). We used #2 SPF 2x6s, ends cut at an angle to mate with the post sides, and placed against the inside faces of the girts. Nail through each girt into the corner braces (10D ring shank). If you have a walk door in a building corner (common to many designs) you can go ahead and frame out that opening. A walk door in the corner will be in the way of that corner brace. OK to use another convenient sidewall bay for the corner brace in that case. NOT OK to omit that corner brace!

Next installment will be on swinging trusses, roof framing and final framing.

-Paul
 

JeremyBX2200

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Thanks. I plan on adding a pole barn in the next few years. Never built one before, but think it could be a fun project.
 

pigdoc

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Thanks. I plan on adding a pole barn in the next few years. Never built one before, but think it could be a fun project.
Thanks Jeremy,

As I hope you'll appreciate, there are a TON of tricks-of-the-trade that make projects like this flow smoothly to the finish. Took me years to appreciate many of those. I'll try to share as many as I can think of. In the meantime, you must be resigned to a certain amount of 'tearing out' for rework during the construction. Not a big deal. But it forces you to always think, "Should I hammer this nail home, or leave it tacked?" You'll want a good Cat's Claw (Pussy Paw?) to pull nails that are already hammered home. Though our crew never used them, I would recommend getting a box of "scaffold nails". These are the nails with double heads that make them easy to pull once their purpose is served.

In my previous posting, I kind of put off the discussion of eave purlins, as there are a couple of different strategies for how to use them, depending on how big the building is, how experienced the crew is, etc...

But, here goes.

Eave purlins, in their final installation, establish the tops of the sidewalls as well as the lowest line of roofing attachment. One of the things that results in high customer satisfaction is that everything appears absolutely STRAIGHT to the eye from the ground. Eave purlins are one of those things that, if they're not installed carefully, the result is glaringly obvious, especially if there are going to be gutters at the eaves.

Sometimes, particularly on very wide buildings (with LONG, floppy, heavy trusses), we would temporarily install the eave purlins with their top edges on that horizontal plane that the truss heels sit on. In other words, even with the bottoms of the truss notches at the tops of the poles. For very large buildings, sometimes we would be lacking a few inches in crane lift to get the truss peaks high enough. We'd need to get the truss heels up on something to support them, and then the crane operator could lean the truss to vertical. Trying to land the truss heel in its final resting place at the same time just complicates the process (read, you need more than 5 people to swing trusses). You can let the truss heels settle on the temporary eave purlin near its final resting place, and then scootch (that's a technical term) them into place as the truss is pulled to vertical by the crane operator. For an experienced crew working on a smaller building, this added step is unnecessary. For an inexperienced crew, it's probably wise to go that route: temporarily positioning those eave purlins on that horizontal plane, just to expand the landing area for the truss heels. It's just more forgiving of crew inexperience.

One thing I always thought would be useful, though we never used them on the crew, would be a pair of big-ass C-clamps to clamp the truss heels to the poles until they could be nailed and bolted.

Once the truss heels are secured to the poles, you then remove the eave purlins, and move them up to where they will be permanently. [Hence, the utility of scaffold nails.] The issue with doing that on-the-fly, as trusses are being set, is that typically, the truss heel will need to be trimmed after the truss is installed to provide clearance for the final positioning of the eave purlins. When you're swinging trusses, you don't want the crane operator sitting there, waiting on some minor carpentry. We like to keep him moving, so that the progression from swinging the first truss to swinging the last truss is continuous. Plus, as implied in my first paragraph, you want to take your sweet time in finally setting the eave purlins, to get them absolutely straight, from one end of the building to the other. Your eyeball rules this process...

When you're doing the final positioning of the eave purlins, it's also nice to have them close at hand, all trimmed to perfect (custom) lengths, with nails started in them, so that one guy can hold a purlin end in one hand, and his hammer in the other while his partner hangs on a corner, with his eagle eye on the line, and says, "up/down a skosh....HIT 'er!". So, there is some utility to having the eave purlins all prepared before swinging trusses. Because, once trusses start swinging, there's a lot of work to be done before you can leave the jobsite for the day! That said, moving the eave purlins can always wait until the next morning, when you're fresh.

If I had a good set of photos, I'd write a book...
-Paul
 

pigdoc

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We setup one for a customer last year that became a monolithic slab with the posts set in steel post bases.
When they went to drill the holes all they hit was solid granite at about a foot.
I really like the way that turned out.
Ya, Wolfman. For smaller livestock housing projects (low sidewall height), typically we'd arrive on the jobsite to find a poured stub wall to set posts on. Typically, L-shaped brackets made from 1/4" steel strap would be embedded in the concrete, with holes in the long arm of the L through which to place bolts to secure the poles to the brackets. Satisfactory, but rather unforgiving of small adjustments needed during the build...Often, the brackets would be a couple of inches away from where we wanted them! And, what happens after the brackets rust off?

I often thought that, in Wick's building designs, there was opportunity left on the table to maximize resistance to wind. This was partly the result of the buyer nickel-and-diming the project cost. You know farmers...

In the same light, particularly with non-professional builds, the lack of proper bracing is often...appalling. I can't walk into a pole barn today without giving it the stink eye!

Also, there's something about having 3.5-4 feet of pole into the ground that contributes to lateral stiffness. We would actually select which end of every pole went into the ground so that there was not a big knot right at ground level. [An advantage of laminated poles.]

That concrete stub wall offers a pivot point for the wracking that occurs with high winds...For smaller buildings, this danger is subcritical. But, some of the larger buildings we built (e.g, 78x200 clear span with a 16-foot sidewall!) you need all the wind resistance you can find! Bracing, bracing, BRACING!

Speaking of wind, a mildly spectacular failure is when large sliding doors flip up and over to land on the roof! This is a consequence of failing to use critical door-securing hardware properly.

-Paul
 

Ridger

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Thank you for the very detailed information. It's obvious you have a lot of experience in constructing pole barns. I had a pole barn built on my property a couple of years ago. I looked at various contractor websites to get ideas. I really liked Wicks buildings and the design tool they offer. Unfortunately, they didn't build this far south.

I went with a local builder and have been very pleased so far. The one thing I insisted on was using UC-4B preservative on any wood going in the ground. Most people, including many contractors, don't realize there is a difference in the wood treatment process. I had to special order my 6x6 UC-4B treated posts because the local building supply stores don't stock them. So a word of caution to anyone planning to build a pole barn, if you are going to put wood in the ground for foundation purposes, make sure it is treated to UC-4B. I've attached a wood preservative guide for more information.

Another interesting note. The US Forest Service operates the Harrison Experimental Forest in southern Mississippi. They have been treating wood posts and testing the durability of preservatives since 1939. They have published some very good papers on the results of various preservatives. You can search for them and read them online.
 

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pigdoc

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OK, time for the THIRD installment.

3. Truss installation.

At this point, you have your framing well-along and everything is permanently secured. In-and-out braces on sidewall poles are still in place, and you've plumbed up every pole (except the corners, which are already plumb) by adjusting the braces. Make sure that the end wall poles are also braced perfectly plumb.

Once truss setting starts, you can tolerate no interruptions - it needs to progress rapidly and continuously until everything is secured. There is a bit more advance prep to do before you pick up the first truss (actually, the end rafter).

In this construction, we will install 2x4 purlins on edge on the top edges of the trusses, edge nailing a 40d ring shank through each purlin and into the truss. [I'll cover purlin installation near the end of this posting.] The advantages of installing purlins on edge like this are: First (and foremost), they're stiffer when oriented that way and can thus better support snow loads. And, you can use roof screws longer than 2 inches (say, 3 inches long) to better secure the roofing. [One of the principal reasons that roofing fails is that the screws (or nails) securing it get pulled out of the purlins. Wood that remains wet around a steel fastener eventually develops "iron sickness" and loses its grip on the fastener. So the longer the fastener, the more secure it is, and the longer your roof lasts.] Not only that, but you can go back 20 years later and re-fasten if necessary, using an even-longer screw.

Earlier, you selected 4 of the straightest 2x4s for each bay, two for eave purlins, and two for ridge purlins. Eave purlins are already temporarily installed, ends butted, in a straight line on the plane on which the truss heels will be set. (Or, in other words, at the bottom, horizontal edge of each truss notch on the poles). You marked a line for that plane on each pole by measuring up from the still visible transit line. You've eyeballed both lines of eave purlins (each side) from each end and straightened as necessary.

Now, you can go ahead and mark and cut the truss notches on the poles with a chainsaw. [Don't bother to cut the tops of the poles off now. That will be done after purlin installation.] The bottoms of the truss notches are flush with the top edge of the temporarily placed eave purlins. This gives you a convenient and secure place to rest the truss heels as you skootch them into their final position during installation.

Next step is to build the ridge purlins. These are critical for truss placement, as they allow setting the trusses perfectly vertical, on-the-fly, one-by-one as you set them. A simple way to lay out the ridge purlins is to just to lay them in a row the length of the building on top of a waist-high girt on the sidewall. One by one, accurately cut the ridge purlins to length, looking up to the top of each post to note which side is notched, and making the ends of adjacent ridge purlins butt on the CL of the yet-to-be-installed truss. If your building has 9-foot bays, start with 10-foot 2x4s and you'll have a pile of blocks about a foot long as scrap. Now, face nail one of those scrap blocks to an end of each purlin lapping it halfway. Leave the ridge purlins for the end bays their full 10-foot length, leaving an end to hang out past the building endwall. [Gets trimmed after roof-framing is complete.]

Here is a bird's eye sketch of the sidewall structure to illustrate:
1694965650788.jpeg


It's a little hard to decipher, but I'm showing two girts butting (dashed line) in the center of a sidewall pole, with two ridge purlins laying on edge on the girts' top edges. The ridge purlin on the right has the block nailed to it with three 10d ring shank nails. Lay out your ridge purlins with the blocks all on the same end of each purlin. Start a 40d ring shank nail on the CL of the truss (nail head shown in diagram). This nail is your guide in placing the truss. When swinging trusses, just drive that nail on into the CL of the truss near its peak, and you can be assured that the peak of the truss will be on the exact same vertical plane as the heel which lies in the notch on the pole. In this diagram, trusses will be set down the length of the building working from the right hand side. Note: the starting ridge purlins for the end bay each get TWO 40d nails, one for the end rafter, the nail at the other end of the purlin for the first truss after end rafter.

You only need to lay out one of the two ridge purlins for each bay this way. [The other ridge purlin for that bay doesn't need to be laid out, it just needs to be the correct length for the bay, which may vary depending on which sides of the poles the two adjacent trusses are placed. If every bay is 9 feet, then all the ridge purlins will be the same length: 9 feet.] Now, you can see why it's critical to get your poles placed exactly on 9-foot centers. Saves a LOT of custom cut work on girts, eave purlins, and ridge purlins!

Finally, mark each truss upper chord near the peak for the top edge of the ridge purlins. If you're going have ridge vents, this may require some careful layout so that the gap between each pair of installed ridge purlins is to spec for the ridge vent.

OK, now you're actually ready to swing trusses! Typically, you need 5 people for this job:
- One to run the loader tractor. We used an extendable box-steel boom that hooked on the bottom edge of the loader bucket and with two stabilizing rods pinned to the upper corners of the bucket.
- One guy on the ground to guide the hanging truss and toss purlins up. We picked the biggest, buffest guy to toss purlins.
- One air guy at the top of each of the two poles that will support the truss.
- One air guy to shimmy up the upper chord of the previously set truss.

First the end rafter. It's very difficult to get the first end rafter installed accurately if there are no installed trusses to index from. So, it gets installed temporarily in a position that's close to final. There are various ways to secure the end rafter to the poles. You can use blocks nailed to the posts to support its weight. And, big C-clamps to clamp the upper chord to the poles. Or, just nail it, with the expectation that you may need to pull most of the nails later to get it adjusted into final position. Hopefully, just nail it up with the heels at the correct height, and hope that the engineers got the length and pitch correct. But, that end rafter needs to be up there before you swing the trusses, because until framing is complete, those end wall poles and the ridge purlins are going to be the only things keeping the trusses from tipping over like dominos.

Now, the trusses, one-by-one. Our crew could swing and secure ten 60-foot trusses in a couple of hours.

The truss gets lifted by its peak, so that it hangs close to level. As it's lifted into place, the two air guys at the tops of the poles skooch the heels into place and nail them to the poles (a couple of 20d ring shank nails is sufficient for now). Then, one of those air guys shimmies up the upper chord of that truss to the peak. We picked the youngest, most fearless guy on the crew for that, and it was usually me.

General safety rule: Don't look down, look at where your next footfall will land.

Meanwhile, the air guy on the previously set truss (or end rafter) has shimmied up to the peak, and the ground guy has tossed him the custom ridge purlin for that bay. He extends the proper end of the ridge purlin (the one with the block nailed to it) across the open space to me, at the peak of the truss being swung. I place the edge of that ridge purlin on the mark on the truss, slide it lengthwise to align that started 40d nail with the CL of the truss, and nail it home. Then the air guy on the previously set truss pulls or pushes the other end of that ridge purlin until it butts against the previous ridge purlin and nails it home. Reach across and install the other ridge purlin, then unhook the just-installed truss from the boom and done. We both shimmy back down for the next truss.

If you've laid out the ridge purlins correctly, as they're installed, the end that is not blocked butts against the previous ridge purlin, sits on the truss, and gets face nailed to the block on the previous purlin with three 10d ring shank nails. This way it's a no-brainer to get the trusses properly positioned during installation.

So now, you have all the trusses in place. But, they're very poorly secured at this point. So, there is lots of work left to do - purlin and brace installation.

[Reached 10,000 character limit. See next message.]
 
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pigdoc

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[See previous message for first part of this installation.]



After a quick water break, it was on to purlin installation. We would work one bay at a time, with two air guys on each side of the building installing purlins, and the guy on the ground tossing purlins. Ahead of time, we had cut 4 blocks to the proper length for purlin spacing. [This length was specified in our plan, but you can easily calculate it from a measurement of the length of the upper chords to make the purlin spacing equal from eave to ridge. We'd tack two nails into each spacer block on the bottom side, midway along the spacer's length, and 1.5 inches apart. That way, it sits on the top of the truss upper chord and doesn't slide off in use.

For purlin installation, using our spacer blocks, each guy in the pair would handle one end of a purlin, nailing it on edge to each truss (40d ring shank), starting at the eave and working towards the ridge, one bay at a time. Using 10-foot purlins on 9-foot bays, conveniently, each end of the purlin laps on its next-bay neighbor and get face nailed to it with 10d ring shanks, as well as edge nailed with a 40d. [At the building ends, the purlin ends are placed flush with the outer face of the end rafter.] We'd also toe nail a 10d through each purlin's top face into the truss upper chord, so that the purlin did not tend to tip and pull away from the truss when walked on. [It was a common habit to just walk on the purlin top edges to move from eave to ridge.] In my prime, I could drive a 6-inch long 40d ring shank nail into yellow pine with just three swings of my 22 oz Estwing waffleface. The hardened ring shank nails that we used actually had a pattern in their heads to grip the points on the waffleface. By the end of each summer, I had carpal tunnel syndrome in my right wrist.

Purlin installation progresses very rapidly, and quickly uses up the ground guy tossing purlins up if it's a big building! A crew develops a rhythm that makes them very efficient. We'd just extend our open left hand downwards, and within a couple of seconds, a 2x4 would appear in the immediate area. Often, you just had to close your fingers to grab it. Sometimes, if there was any bow in the truss upper chord, we would first need to temporarily install purlins midway up the upper chords to straighten them.

Now that purlins are installed, you can eyeball the roofline to move the first end rafter into perfect position and permanently secure it. The last end rafter was accurately placed as you finished swinging trusses, because you eyeballed down the already installed ridge purlins to get it to the correct height. We put two 1/2-inch through-bolts in at each truss-pole connection, usually, the next morning.

Next is knee braces, for each sidewall pole. These are to prevent flexing of the structure in-and-out and were pre-built for us, consisting of a sandwich of two 2x6s. One 2x6 lapped the lower chord of the truss and the pole. The other 2x6 was shorter and had angles at each end to perfectly match the bottom edge of the truss lower chord and the inner face of the pole. Good idea to recheck poles for plumb, because after the knee braces are installed, you are not moving the poles any more! We just nailed these in - 10d nails for the truss, 20d nails for the pole. Once the knee braces are installed, all temporary pole bracing can be removed.

We would finish up the day by installing wind braces. These are placed diagonally from the peak at the end walls down to the eaves. Again, one air guy on each of two adjacent trusses. Ground guy tosses up a 16-foot 2x4, and the air guys hold it up against the bottom edge of the upper chord and mark the angle on each end. Send it back down for cutting, toss it back up, nail it in place against the faces of the truss upper chords and against the bottom edges of the purlins. Usually, 12 wind braces on a big building, spanning 3 bays from the end rafter, on both sides of the building at both ends. We NEVER left the job site before installing knee braces and wind braces!

Now, it's starting to actually look like a building! Typically, our crew would be at this stage at the end of Day 2. Virtually all the lumber on the site (two semi-truck loads!) was in the air by then.

We had rule on my crew. Air guy who dropped their hammer had to buy the first round at the end of the day!

Back in these days (1976-1979), we had no air tools. All the framing and siding was done by hand, or by 'lectric (saws/drills). As I think of it, there was no incentive to use air tools, because most of the work was air work, and air tools are (were) heavy. The hammer was sacred. And, the hammer ruled. Heck (spit) we never used any screws! Everything was still being nailed back then... I'm pretty sure that all of the dozens of buildings I've built with nothing but nails are still standing!

Hope you are enjoying this virtual build!

Next installation will be on final framing details and siding installation.

-Paul

PS, this series is bringing back many fond memories of my first serious forays into the labor market. We had a tight crew, and frequently rode together to rendezvous. It was really fun to find that extremely productive rhythm, mainly by exploiting the individual strengths of the crew.

Something to be said for being able to stand back at the end of the day, and have your field of vision, horizon-to-horizon, filled with stuff that YOU built! I was so happy to be working for $9 an hour.... (that was 1976).

I used to get home and down a half-dozen ears of sweet corn for supper, just for starters. I was 19 years old....<sniff>
 
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Molelaner

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Aug 28, 2021
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usa
Your post brings back memories of my summers building pole barns – great times! Solid advice on planning and layout. The tip about going "up" for cost efficiency is gold. I'd add, consider your door sizes wisely; wider is better. And hey, considering the intricacies involved, a nod to a skilled Structural Engineer Brisbane could be a game-changer for anyone attempting this project.
 
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wp6529

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B7100DT
Oct 31, 2023
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TX
Your post brings back memories of my summers building pole barns – great times! Solid advice on planning and layout. The tip about going "up" for cost efficiency is gold. I'd add, consider your door sizes wisely; wider is better.
Definitely take advantage of UP. Friends build a big barndo with an 18' eave height. I told them to find a used forklift and a palette rack for the shop area. They took my advice and now have about 80' of palette rack three levels high.
 

mcmxi

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Lifetime Member

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***Current*** M6060HDC, MX6000HSTC & GL7000 ***Sold*** MX6000HST & BX25TLB
Feb 9, 2021
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NW Montana
@pigdoc , just want to say thanks for sharing your experience and taking the time to make these informative posts. I'm going to put up one or maybe two steel pole buildings this year. I'll be welding up trusses and sitting them on steel poles set in concrete.