Replies

1. 
   Guest_ | Mar 24, 1999 05:49am | #1

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   There should be drilled holes in your I beam every few feet to bolt a 2x4 on the flat to...then set joists on it and nail...Who ever does your plans will give you your detail.

   J

2. 
   John_W. | Mar 24, 1999 06:23am | #2

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   the joists won't be sitting on top of the beam.i want to keep the cieling flust below.Can i bolt lumber on sides of beam and connect the joists with metal teco's?

3. 
   Guest_ | Mar 24, 1999 07:45am | #3

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   It depends on the engineering that was done for the beam...My method is for either on the top or bottom flange.

   Who is doing the engineering? I don't do my own, I hope you don't do yours...

   J

4. 
   Dave_R | Mar 24, 1999 08:21am | #4

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   Try using a powder-actuated nailer to install a 2x nailer to the top of the I-beam--the nailer should be ripped to the same width as the I-beam. The nails should be shot in about every 24". Then use top flange hangers to install the joists. As an alternate you can weld 1/2" bolts on to the top of the beam to secure the nailer.

5. 
   Guest_ | Mar 24, 1999 09:03am | #5

   *
   

   View Image

   W, WNP, HW

         Hangers may be welded to steel

         headers with 1/8" for W, 3/16" for

         WNP and 1/4" for HW by 1 1/2"

         fillet welds located at each end of

         the top flange.

    

   View Image
   
   

1. 
   Guest_ | Mar 24, 1999 05:37pm | #6

   *John these are all interesting suggestions that you are getting, however, could you fill me in on what you want to accomplish on the OTHER side of beam. How were you planning on finishing or attaching the soffit structure? If your using or need a 16" I beam then I presume that your spanning almost the entire width of your house.If this is the case you're going to forget the cosmetics of a flush beam and follow Jacks first posting. Drill and install a plate followed by the joists on top.

6. 
   John_W. | Mar 25, 1999 03:25am | #7

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   The beam is going to span the living room below with 12' and 14'joists going to the front and back walls of the house.i wanted it flush so the cieling below would not have a header dropped down acroos the middle of the room.

1. 
   Jay_ | Mar 25, 1999 09:41am | #8

   *What is going to be above this beam? is there a floor that is expected to be flush, or is there a wall you can hide part of the beam in? the reason i ask is that your first post mentioned attaching 2x8 joists, if both top and bottom are flush, the beam can only be 7.25" deep, not much of a beam to span 16'.It sounds to me like you are desiging this yourself, otherwise the conections would be detailed on the plans. You probably should have an engineer look at this. If you go with top mount hangers (which would have to be weld on if you are to have any hope of keeping both top and bottom flush with a 2x8) you will need to be sure the bottom of the beam is restrained somehow, 'I' or 'W' beams do not resist torsion particularly well. Ofcourse if the beam is flush with the joists, the flanges will be trapped between pairs of joists, but I would add steel straps across the bottom to make sure it stays that way. However, I have trouble imagining a 7" deep beam working here in the first place. Jay

7. 
   Guest_ | Mar 26, 1999 06:13am | #9

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   Good deducting Jay!

   In my neck of the woods, they weld a 1/4" x 11" continuos steel plate to the bottom of the beam. The plate hangs out, on both sides, and provides bearing for the joists. This is very common, and I have been involved, as a user, and a fabricator for 25 years.

   Blue

1. 
   Guest_ | Mar 28, 1999 01:09pm | #10

   *John,I'm using a W6X25 to span 14'. It's supporting two floors. Tributary widths are similar, so it's conceivable a W6X25 could support the roof only, spanning 16'. My 2X8 joists are attached by bolting 2-2x6 to each side with 1/2" bolts 12" OC through the web, then standard JUS-28 hangers. A 1X8 ripped to width makes up the difference in the height of the beam. My application was engineered; I suggest you do the same.Blue,The plate on the bottom seems simple and easy. Would you have to notch the joists to keep things flush?Jerry

1. 
   Guest_ | Mar 30, 1999 01:28pm | #11

   *A notch is only required when you don't set the beam at the correst height. The idea of the plate is to eliminate notches, and just set the joist on the plate.Typically, we use this plate system for dropped floors, usually a family room or sunroom.Blue

1. 
   Guest_ | Mar 31, 1999 04:30pm | #12

   *Blue,I was refering to keeping the ceiling flush but at the time I posted I didn't have a clear picture in my head. Got it now; thanks.Jerry

1. 
   Guest_ | Mar 31, 1999 11:55pm | #13

   *JohnI either missed something here or your building code are a lot different in the U.S..I take that youre "I" beam is running at right angles to your floor joists, if so just notch out the thickness of the bottum flang on the joist, slip them into the web of the "I" beam and fit solid blocking between joists to stop them twisting. Job sorted, flush ceiling, no ploblem, In the uk we do this all the time just apply 1 hour fire protection under beam = 2x 1/2" layers of plaster board.Right now I can sit back and wait for all the replies telling me that you cant do that in the states.Martin m (mad mack)

2. 
   Guest_ | Apr 01, 1999 02:53am | #14

   *Are you saying that nothing holds the joists to the beam but gravity?

3. 
   Guest_ | Apr 01, 1999 06:14am | #15

   *HeyThey're Brits. . . i it can't fall down because there's nothing holding it up

4. 
   Guest_ | Apr 01, 1999 05:36pm | #16

   *If there is a flaw inthe sytem that you descibe, it would be in the bearing. Many wide flange beams would have an adequate amount, but a regular "I" beam would not. Additionally, the flange is sloped, and would not make a particularly good bearing point.I have also simply fitted joist into a wide flange, but would rather see the plate welded on the bottom. The biggest reason is framing time, and since I am only concerned with labor...Incidently, a 16' span will be a very large wide flange beam, and the bearing will probably be adequate.Blue

5. 
   Guest_ | Apr 05, 1999 06:29pm | #17

   *I had a sitation simular to this and I was told by the architech and engineer to drill holes in the web and bolt 2 x's in as a nailing surface for hangers. This worked much like Mike's idea only his looks easier. With his method the only thing I would add is notching the joists to rest on the flange as a little extra insurance.

6. 
   Guest_ | Apr 08, 1999 09:13am | #18

   *Hey Blue, here's a dumb question, but I really don't know much about welding. How strong is a welded joint? is it as strong as the steel it welds? When you use the method you describe do you only rest joists on the steel plate that is welded on, or do they go to the web? With out a little notching how do you get the ceiling flush, doesn't the steel plate hang a 1/4" lower than the plane of the ceiling?These are really only legitimate questions about a different way of doing things. I like the sound of you method, when I had to drill 30+ holes in a 32' beam to attach wood it was very time comsuming, but that is what the plans called for.

7. 
   Guest_ | Apr 08, 1999 06:04pm | #19

   *JD,Never order a steel beam before you have a plan for it's use. With that plan you will be describing in detail all holes and other modifications to be performed b beforeyou take delivery of it...Sound like a better b plan?Near the stream letting my steel guy drill the steel. (He has a onsite service too!)J

8. 
   Guest_ | Apr 09, 1999 06:13pm | #20

   *Jd, the beams with plates are typiclly used for a dropped family room, on the first floor. We usually just rest out joists on the plate. If the basement ceiling were to be drywalled, there would be a 1/4" difference that I would not be too concerned with, unless there was some specific application that required perfection. There is ALWAYS a differential of 1/4" or more in a normal load of joist, due to different crownong. Some FhB'ers might pull out their jack planes and plane the joist true, after erection and acclimation, but I just use heavy glue to shom the low areas, and board right on over it.Welds are stronger than the steel itself, and it is up to the structural steel supplier to get the proper amount of weld per foot to make it safe. I use to do this type of welding, in the supply yard, and in the field, and although I was not the greatest welder (it's an art, and I was more interested in the young ladies), I never had any call backs. Bolting would be a labor intensive alternative, even if the holes were predrilled (actually we burned them). After bolting, you still have many joist hangers, and bolt drilling and tightening.Cost wise, it's probably a push. I'd always go with the plate.Blue

8. 
   Woodchip | Apr 17, 1999 07:39am | #21

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   I had the same situation about 5 years ago. Flush steel had to be used because the second floor joists were only 2 X 8 and 12 foot span per side of removed wall where steel flush girder was going. I had to cut the ends of the joists where they overlapped to the section of the steel girder and slide the girder in from the end like a needle. I had prepared 1/8 inch steel strapping predrilled with two holes each and pre cut to be the sides of my "hangars" the saddle of the hangar was actually the bottom flange of the girder.. When the girder was in place I used my portable mig wire feed welder to weld the sides of my hangers to the top and bottom flange of the I beam, holding them out about an inch from the web. I even made a three way extention cord for my welder to provide the 220 volts needed in the living room by finding two 120 volt circuits in the same room wired to separate phases of the electrical service panel. No need to run to the basement to hot wire into the service panel or find a too distant 220 circuit. but I digress :-). Anyway the steel installation went beautifully and I enjoyed welding so much I welded the 2 X 3 .180 wall steel columns to their pads and welded same to the lower flange of the I beam. The hard part was relocating two duct runs thru a hump in a closet by raising the closet floor 4 inches over the I beam. As a footnote the lower flange had an additional flat plate I welded to it to bring the assembly to the engineered specification.

9. 
   Guest_ | Apr 24, 1999 04:16am | #22

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   My question is what is supporting the steel beam?
   There are a number of different ways to connect wood joists to steel beams (2x (should really be a 3x min. for nailing) plate bolted to the top flange and use top hung joist hangers, 2x plate attached to the top of the bottom flange, etc.) but the real concern is how does the load from steel beam get transfered to the foundation.

1. 
   Guest_ | Apr 25, 1999 03:15pm | #23

   *Stanchions.Blue

1. 
   Guest_ | May 19, 1999 05:12am | #25

   *RdOn the houses I build the engineer calls out how the steel's load tranfers to the foundation. Sometimes they will use a multiple 2x, glu-lam or micro column to pick up the steel. The load is tansfered all the way to the foundation the same as any load would be. Other times they will use a tube steel column either welded or bolted to the beam. Typically the steel column will have a base plate with two holes. The steel is usually a 1/2" short. We shim it up to the beam with steel shims, bolt it down with anchor wedges and then fill the shim space with non-shrink grout.When wood is used I like to lag the beam down. Most of the steel i use comes from the lumber yard and is not drilled, we have to drill. The engineer of the house we are on now said the steel beams do not need to be lagged to the wood columns. We'll se what the inspector has to say.I am going to put a high dollar charge per hole that we have to drill in my contract. Maybe the owner or the gc will then make sure they are done before the steel gets to the site.On most of the steel beams we hang the joist like Rd said. With a 2x plate glued and shot to the top of the beam and top flange hangers. I am always carefull to make the 2x top plate a 1/4" wider than the beam. I once had to fix a squeek on a house I was trimming because the 2x was flush with the top of the beam. The hangers were rubbing the steel.

10. 
    John_W. | May 19, 1999 05:12am | #24

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    I'm installing a 16' steel I beam as a flush header for a second floor dormer.What's the best method for attaching the new 2x8 floor joists to the i-beam?