Building a Steel Barn

[MarkV]

@AlanB - yeah, the entire shop is steel - trusses, legs (posts), purlins with galvanized tin 'skin'.
Thats a good idea on starting at the center. I was thinking of just picking the shortest set post and shooting to all the others and cutting them off, but starting in the center might accomplish the same thing?

I'm definitely going to fuss over it a good bit. I guess part of the fun of building it is playing with the details

Thanks!

Thanks for explaining the materials more. I for some reason thought we were talking wooden posts and setting them 2.5' deep. I now see you are talking about a 2.5' deep footing for each post. How does the post attach to the footing?

MarkV

 

[Raspy]

rmasonjr,

I'm still unclear on what you are doing. Bear with me.

On my steel posts that sit on concrete, I have bolts sticking up out of the concrete. Then the posts set on the bolts with jacking nuts under and lock nuts over the post foot.

I measured from the bottom of one post with a tape measure and took a reading with a transit. Then I measured all the rest and adjusted them to match. It turned out to be a bit tricky to get the lowest one high enough to begin with and the lowest one was my starting one.

Next adjust them to verticle without changing their height.

If you have some without bolts pre-set, as I did, you can set them on blocking and shims. Then mark the concrete footing, move the post a bit and drill in an anchor bolt. For these, use 3/4" or the size of your choice, threaded rod in grade 8. Drill a larger hole, I used 1", to allow for imperfect drilling. Cut pieces to length and epoxy them into the drilled holes with the jacking nuts and lock nut installed as you go. Try to get 6" penetration minimum and use Simpson bolt setting epoxy as it's approved for this use and will break the concrete before pulling out. Or you can use bolt setting, expanding mortar that sets in munutes. If you use this method screw on an extra nut that will be buried in the final slab. Be careful to keep the posts in alignment, both verticle and in line with the other posts. Run some strings and use some tie straps, clamps, stakes, 2 X 4s, etc as needed. Pry against other posts, the tractor bucket or a stake to stabalize till the mortar or epoxy sets.

If you choose to use this method you'll end up with the whole building sitting there on bolts that will get grouted in or poured in with the final slab.

It's very important to check your transit or laser level for accuracy!! Do this by taking readings in opposite directions to verify consistency before you commit. Before I got a good transit I had to take two readings on every post from opposite directions and average the difference to get a good number. this was very frustrating and time consuming. It also required a chart be made and updated as I went along.

I was able to get all my posts to within about 1/8 inch. They could have been closer but for pre-cast bolt problems.

I don't subscribe to the "within an inch or two is fine" theory. Do the best you can all the way up to avoid big problems later. With the jacking bolt method you can visually sight up along the trusses and end wall beams. You can see how straight they are and adjust as needed.

Be sure you have a good work platform! I made one from an entrance gate that is made of 2" square tubing. It has a gate that opens in and is about 6' X 3'. A very secure place to take up purlins, wrench on bolts and have lots of tools handy without fear of falling.

 

[crazyal]

How soon are you thinking of doing this? If you have a couple of weeks before hand I would suggest buying a laser level off of ebay and then selling it once you're done. I have a relitively cheap one but not Chinese made. Here's a link to a new one.

Spectra Percision Laser LL200 - eBay (item 120591313049 end time Jul-12-10 13:50:51 PDT)

I have seen other used ones sell for about half that and if you can wait until a better price comes you could sell it for about the same price you pay for it. I've been extremely happy with mine and decided to just hang onto it.

It uses an invisible laser and a receiver that has both an LCD arrow telling you if you are high, low, or in-line as well as a tone, fast pulses means you're too high, slow pulses too low, and solid tone for level. You set the tripod up sort of level, it has a bubble, and then it self final levels. I've used it for leveling the forms for my garage's cement slab, setting grade for drainage pipes, as well as several other projects. After 5 minutes at most you'll be an expert.

 

[Mace Canute]

A real cheap method is some clear tubing and some water colored with food coloring.

Water tube level You can Google and find ,ore examples.

Years ago, I bought a small water level kit that supplied the clear hose ends that would thread onto the ends of your common everyday garden hose. It was on sale for cheap, and I thought it was one of those things that if I ever needed it, would sure make the job go easier. It's around somewhere....

 

[Hawghauler]

My first shop the builders left a good 6 inches extra sticking up on the posts and it turned out to be a blessing as they did a poor job in compaction and the posts settled on one side which was starting to ripple the metal. They were able to raise the cross beems and re-adjust, accounting for the settling and the shop was fine. (all warranty work). Just a thought.

 

[dfkrug]

I was thinking of some laser-leveler to shoot from leg-to-leg and cut off the tops, but not sure what to use.

I am also working on an all-steel building. To determine the exact length
of the columns, I use a laser tool called RoboLaser, from Toolz. I bought
it when it first came out back in the mid 90s, and I used it extensively
to get my grades correct in digging the foundation for my house.

It is a motorized self-leveling laser that is remote controlled. It sends
out a dot that is visible in daylight (no special detector needed). The
remote turns it on/off, and rotates the body of the unit. I mount it
in one location on a tripod and mark where the dot hits my columns.

Toolz is now RoboToolz, and the device has been improved. There is even
a super-bright green laser now, good for 300 ft, instead of only 100 ft.
You can find the older tool used, or pay $100-150 for the newer one, new.
Several people I know bought these after seeing mine work, and how
reasonable it was.

 

[Raspy]

Here are some more pix of our project. Next is the roof.

 

[Raspy]

More pix

 

[Raspy]

Still more

 

[Raspy]

Some things that have really been helpful with this project are the basket for the forklift made from scrap steel, the A frame in the tractor bucket made from 1 1/4 inch pipe and chain, the tractor which has moved many, many tons of material, dug the foundation, dug about 700 feet of ditch, dug the septic tank hole and graded the whole area.