Wooden Joists Placed Directly on Steel I-Beam 1

[ADCanada]

Hi to all
Due to space restrictions, is it possible to place the wooden joists directly on an I-Beam without having any wood nailer between the wooden joists and the I-beam, it is noted here that at the end of the joists there is a 2 1.3E LVL's (i.e. the LVL's are running along the I-beam) ... and to restrict the I-Beam from lateral movement an angle is suggested to be welded on the flanges of the I-beam and have a bolt fasten to the LVL's...

Is there any structural problem with that?

 

[BAretired]

Don't know. Provide a cross section through the beam.

BA

 

[hokie66]

I would prefer plate cleats on the steel beam for bolting through the joists.

 

[ToadJones]

Can you raise the "I-beam" up and frame joists into the I-beam?

 

[woodman88]

Yes you should be able to. But you still need to meet the minimum code connections requirements for the joists. Such as hokie66 idea.

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.

 

[Eldorado]

Using cleats (hokie66) or raising the beam (ToadJones) both seem to be good options. If raising the beam is an option, I would use it. I don't know loads or joist depths, but I commonly hold my steel beams down 3" to apply a double 2x nailer to the top flange for accepting Simpson type hangers. The 3" wood nailer is typically a minimum for the hanger fasteners I need. The beam can also be brought up flush with the top of the joists and hangers welded to the top of the beams. If you use a wood nailer, make sure the width is slightly wider than the steel beam.

 

[dhengr]

You can also pad-out the stl. beam on each side and use std. joist hangers nailed into the padding members. Set the top of the new joist a little higher than the top of the stl. beam. The joist will tend to settle in the hanger a little and it will also shrink perpendicular to the grain. So if you set them both at the same elev. you will end up with a hump in the floor above right over the stl. beam.

 

[MiketheEngineer]

If I am reading this correctly - done all the time. Many guys use a "cleat" or 1x2 nailer on both sides of I-beam to joists. I have even seen 16d nails on each side of I-beam. Can't say I approve of that - but probably works??

 

[hokie66]

Mike,
Ever tried driving nails into a steel beam?

 

[shobroco]

Wooden joists are placed directly on beams every day of the week (literally) and the condition is recognized in the OBC by stating that without a wood plate on top (assumed to be bolted to the beam) there must be a cleat on each side of the beam to restrain the top flange. It isn't a great detail for the simple reason that the floor will squeak forever (refer to hokie66's comment).

 

[ADCanada]

Wow you guys are great.. this is my first time in this forum and i like it...

From what i read in your comments (i mean all of you) and from what i was researching I apploaded a sketch that explains what are my intentions and what problems i am facing here:

http://files.engineering.com/getfil...b-fbea-465e-8487-d738fe63415d&file=img002.pdf

1.The steel beam is the minimum size that can be used due to deflection...and the client did not like the idea to go with an alternative steel beam since it will result in a wider beam.

2. There is a series of 4ply- 2"X12" pressure treated to form the balconies. And below the I-beam there is the balcomny door for the floor below.. sorry (ToadJones) there is no room to play here.

My solution from what i have researched today and to what i was reading on your replies to the thread are

A. Additing a 2"x4" Scabber to help the framer in aligning his 11 7/8" deep floor joists.
B. Adding a steel angle which can be welded on the flanges of the beam, and having the vertical long leg bolted with the 2 LVL's...

From A and B I guess i will be satisfying the minimum requirements for connections.

(shobroco) do you think my detail will still make the floor squeak?
(hokie66)& (woodman88) what is your opinion about the detail?

 

[shobroco]

I would delete the angle, it's overkill for lateral restraint & the wood I manufacturers won't let you notch their bottom flanges to clear it. Specify an adhesive (PL Premium or something) between the joists & beam to stop the squeaks. You probably wouldn't have a problem anyway because your beam is not in the middle of a floor getting frequent traffic, it's at a wall.

 

[msquared48]

shobroco:

The verticle angle is placed to the side of the joist and the horizontal leg is faced away from the joist being nailed to it, so there is no notching required.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[shobroco]

Then I misunderstood the OP and the sketch; he says the LVLs run along the ends of the joists, which means the joists butt into it. If so, they sit on top of the angle in the sketch, which is okay as long as the top of the angle is set to height, not the top of the beam. The way I read the sketch the joists are to the left & an exterior deck with joists parallel to the beam is to the right.

 

[BAretired]

I think there is a problem in understanding the intent of the detail. I Joists to the left of the steel beam are bearing on the top flange. I'm not sure of the location of the four 2x12 cantilevered for balcony. Where is the balcony?

The angle connected to the top of beam is discontinuous, right? It is connected to two LVL members, one of which is continuous and the other fitted between joists.

I don't think we are all seeing the same picture here.

BA

 

[shobroco]

It's not the first time that I haven't seen the same picture as everyone else. Ask my wife about the last movie we watched together

 

[msquared48]

You have to open your eyes when you watch the movie!

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[shobroco]

Oh, you've seen that one too.

 

[dhengr]

Since that detail is so well thought out and delineated that several Structural Engineers can’t figure out (agree on) what it shows, it will be interesting to hear and see how it actually gets interpreted and built by the contractor. It is almost always ‘funner’ if there are multiple interpretations for a given detail, keeps the job interesting. You will probably also want to put a drip pan under the 4-2x12's cantilevered balcony beam members since they have such a habit of leaking. Also, use P.T’ed. lumber for those canti. beams and framing below them. Be sure to study the back span support of those canti. beams and pay special attention to their flashing at the ext. wall. Flash the top and ext. face of those beams since water will run back into the building on or btwn. them. The 2 ply LVL’s (bad terminology) are more than likely actually the rim boards furnished to match the I jsts., not actual LVL’s. Why do you need a double rim board at this location, is it doubled along the whole wall?

Why not put the stl. beam up in the same depth as the I jsts.? Put 2-2x10's or 2x12's inside the web (padding) and use std. I jst. hangers to this padding to support the fl. jsts. Trim the rim board, in height, to fit btwn. the two outer flanges so it has its continuity and put a little padding behind it, to the beam web, and bolt it all together every 16"? In that depth/space you can use any beam width you want. Then, frame a light std. header below the stl beam, for the door below.

 

[bookowski]

Eldorado - Why do you say that 3" (double 2x) is the required nailer for top flange hangers? I'm pretty sure most Simpson specify a single 2x is sufficient.

In general do most people prefer to the top flange hanger to a nailer or packing out the web? If you pack out the web are you still providing a top plate for sheathing attachment?