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I removed a wall between a kitchen and dining room and want to put a bar joist in the space instead of a wood beam. It is a load bearing wall for a single story house. The question is, how do I pick a bar joist that will mimic the load bearing capacity of a 4×12 beam with a span of 10ft.?
Thanks for your insight. Samuel
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What do you mean by "bar joist"?
"bar joist" is 4 pieces of angle iron with round bar welded in between in a triangle pattern.
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http://news.thomasnet.com/images/large/010/10255.jpg“When politicians and journalists declare that the science of global warming is settled, they show a regrettable ignorance about how science works.” Nigel Calder, editor of New Scientist
It's contact the local engineer time, or call the place selling bar joist they should be able to provide some specs.
“When politicians and journalists declare that the science of global warming is settled, they show a regrettable ignorance about how science works.” Nigel Calder, editor of New Scientist
Samuel,
I understand that this type of joist is solely for support of the load on top of it. I remember hearing about this type being used in a high school woodshop. The shop teacher needed some support to hang some clamp racks and assorted loads from the bottom of this kind of design. When the final walkthough was done, he had to pull off those loads since they were pulling on the bottom which could cause a failure.
Just a thought, in case you had any plans to attach an overhead load on that bottom section....
Bill
Bill,
I don't see why a beam like this couldn't be loaded from beneath. Whether the load sits on top or hangs off the bottom is irrelevent when setting up a free body diagram.
I suspect that the high school shop teacher's sin was overloading the beam. If it was designed to support a roof/floor load alone, then it was not designed for the additional loads he was placing on it.
Well if you can't hang off the bottom of a bar joist then I'm in big trouble.
I can't remember how many times I hung 4" cast iron rain water leaders off them cause the pandecking with rigid insulation roof wouldn't support the load, unless I got there before the insulation went down & was able to span some strut to support the load of the hanger.“When politicians and journalists declare that the science of global warming is settled, they show a regrettable ignorance about how science works.” Nigel Calder, editor of New Scientist
can't remember how many times I hung 4" cast iron rain water leaders off them
And if you didn't, then the HVAC guys did, and with two CW and two HW welded pipes perched with those itty-bitty clamps holding the all-thread rack . . . <g>
Which is why the structureal engineer gets bucks, having to guess what sorts of loads will go on that bar joist and in which directions.
Now, a bit of channel might suffice for OP's needs, being narrow enough in depth to get transverse utilities underneath, rather than through (since I suspect that is the reasoning behind getting a bar joist).Occupational hazard of my occupation not being around (sorry Bubba)
a span of 10ft
From the K Series chart, 10' span:
8K1 550 lbs/lin ft total load; weighs 5.1 lbs/lin ft 8" tall
10K1 550 lbs/lin ft total load; weighs 5.0 lbs/lin ft 10" tall
PAHS Designer/Builder- Bury it!
Hi. I'm not sure I understand your post. Do BOTH 8K1 and 10K1 (bar joists) have capacities of 550 pounds per linear foot? Thanks, Samuel
Yes. That's total load. I didn't figure you needed it broken down, but 8K1 is 480 lbs/lin ft live load, 10K1 is 550.
10' is extremely short for bar joists, not much selection. PAHS Designer/Builder- Bury it!