Framing In A Steel I-Beam

[Rich_Winsor]

In the grand scheme of things it doesn’t amount to a hill of beans,

but for me this project has consumed my every waking moment for

the last 18 months. So here is the deal. To get any kind of a workable

floor plan in my farmhouse remodel project I need to replace a load

bearing wall with couple of steel I-Beams. What I’d like to know is

how I-Beams are customarily tied into a typical wall framed with 2x6

studs? In my situation I am dealing with an 8’ ceiling with a span of

about 18’ between 2 walls which are framed with 2x6 lumber. I’m

guessing that some sort of steel tubing with flanges welded on the

ends are customarily used to support the I-Beam but I see no reason

why a 4 x 6 wood beam wouldn’t do the trick. The I-Beams only weigh

12.5 lbs per foot as opposed to about 10 lbs per foot for a Douglas Fir

4 x 12. My plan is to jack the I-Beams up underneath the existing ceiling

joists and then support them with the 4x6 posts to carry the load to the

foundation. I have come up with a design which I think should do the

trick but I would be interested in feedback from anybody who might

have first-hand experience installing I-Beams. Because the ceiling is

relatively low (and I am relatively high, 6’ 6”) it is imperative that the

beams protrude down into the room as little as possible. This is why I

have decided on the steel I-Beam approach as opposed to a 4 x header

or some type of structural composite lumber beam. If I can pull it off I

should be able to encase the I-Beams in a soffit and have myself a poor

mans coffered ceiling.

 

 

Kindly peruse the attached thumbnails and let me know what you think.

 

[HumbleChief]

Rich,

 

I'm not an engineer and this assumes you've calc'd the new I-Beam to carry the loads you'll be carrying, given that, we work with steel quite often and your design should work fine but it's a bit overkill based on the engineered designs I've used in the past. Overkill is typically a good thing (versus underkill - is that word?) but you can get away with a lot less and still be very safe structurally as the 4 X 6 post should provide very strong support. If your 4th picture is accurate you really just need to trap the I-Beams between 2 king posts just like you would with any other beam.

 

Maybe turn the side supports into those king studs and and replace the bottom through bolt with a series of 16d nails, the upper through bolt eliminated and the angle brackets replaced with A-35's. Maybe add a strap across the 2 x 6's. This all depends on the actual loads and structural stresses which can't really be discerned from your post or pics but we use steel all the time and unless it's a moment frame or absorbing any particular shear stresses the construction techniques are really pretty simple.

 

We will often fill the web with wood using tack welded studs to attach the wood fillers, then hang joists from the filler but that doesn't look like your case here. 

 

Be ready for the chorus of don't do anyhting without and an engineer's blessing and this is always good advice but if you have the loads/spans figured out (which almost always takes an engineer) you should be fine.

 

EDIT: Just read again and I see you're replacing load bearing walls. Do those walls contribute to the shear loads of the structure? That needs to replaced somehow if that's the case. Your design will most likely not serve that purpose. Que chorus singing, "Make sure it's engineered properly."

[rlackore]

It looks like you've chosen a W6x12. Span is 18 feet. I estimate your tributaries are approximately 2 feet and 4 feet. Assuming L/240 deflection limit, grade A36 steel, a drywall ceiling and limited attic storage for a live/dead load of 20/5 psf, the steel you've chosen is adequate - midspan deflection is about 7/16 of an inch. End reactions are approx 1.5kip. You haven't mentioned a wind exposure category, but the chosen 4x6 post should be adequate for both the gravity and lateral loads. Of course, all of this is provisional and assumes there are no unknowns; to paraphrase Mr. Rumsfeld, there are things we know, things we don't know, things we know we don't know, and things we don't know we don't know yet.

 

It's impossible to evaluate the connection without fully knowing the loads and the governing code. Frankly, the connection at the plate/sill/foundation is equally important (continuous load path) - this connection isn't just about gravity - it's also about resisting the lateral and uplift loads. I'd prefer to see a more direct connection from the beam to the column, eg steel plates welded to the beam flanges. If you go with your design, I'd suggest solid wood blocking to fill the entire web space to replace the two inside nuts on the threaded rod. As Larry mentioned, the 2x6s on either side of the post should be full-height kings studs, and lose the through-bolt at the studs/post and simply nail-laminate the kings to the post per the NDS. Get rid of the heavy steel angles and use a pair of Simpson H6s on each king to tie them to the wall top plates, and splice the top plates with some tension ties. Again, the bottom connection is equally important, otherwise everything you do at the top is for nothing.

[Rich_Winsor]

Thanks guys, I need to process all that info but

I haven't seen anything yet to dissuade me from

continuing with the I-Beam approach. I figure if

worse comes to worse we can always designate

the great room as a hard hat only area and if the

ceiling does come down we'll just say that it was

San Andreas fault.

[GeneDavis]

Haven't seen A36 used for a while.  It is A50 where I've been, and where that is, the steel suppliers will help with the design of the connections.

[tommy1]

Have you thought about using a flitch beam instead? It may do fine and easier to use. Just a thought.

[Gawdzira]

I think the real problem here is that you are detailing in Solid Works.

[ACADuser]

Rich, nice detail.

 

Difficult to see what connectors are needed without more of the structure.

Uplift, if present must be transferred to the column (post) and to the floor system (foundation).

Note that the floor must be solid concrete or you need to create a bearing pad & uplift resistance.

Not knowing how old this Farm House is the structure can vary quite a bit.

 

See attached for some connector ideas to consider.

Just exploring the options.

 

 

 

 

[rlackore]

Haven't seen A36 used for a while.  It is A50 where I've been, and where that is, the steel suppliers will help with the design of the connections.

 

 

Can you get structural shapes in A53? I thought A53 was just tubes and pipes. I typically spec A572 for shapes, plates and bars. By running the calcs for A36, the OP should be safe if he chooses a higher strength steel.

[Jay_on_Cape]

Rich's diagram shows a *S* shape rather than a *W*...  Might want to switch to a *W* shape Rich.  The flanges are not as thick so they would be easier to punch / shoot the ledger.

[VHampton]

I would recommend the flitch plate method as well. They do not need to be posted onto steel columns as is required with I beams.

 

What you've drawn will definitely work, but check your local codes on the requiremenst for steel posts at each end. Flitch plates can be supported by (3) 2 x 6 posts in our area. I beams need columns.

 

BTW....We design everything with an L/480 minimum which results in less than a half inch deflection on any given beam which spans upwards of twenty feet. A double 1/2" x 11" flitch will have far less deflection than the size that which you've selected. A W6 x 12 works better as a window header that it does a floor girder. Definitely get that checked out by your steel fabricator who may be able to run a beam check if you're going to go this route. A W8 is probably more like it....

 

Very nice details by the way!

[rlackore]

Rich's diagram shows a *S* shape rather than a *W*...  Might want to switch to a *W* shape Rich.  The flanges are not as thick so they would be easier to punch / shoot the ledger.

Good point - I missed that. Probably a S6x12.5. There isn't any W-shape that fits within his designed width and depth.

[Rich_Winsor]

I think the real problem here is that you are detailing in Solid Works.

 

This project is a non-denominational interdisciplinary undertaking.

The original concept was conceived with a #2 pencil on a sheet

of 8 1/2 x 11 graph paper. I took that original and deciphered it 

with AutoCAD to get a workable as built and proposed floor plan.

Feeling the need for 3D details I started creating a 3D framing

model with SolidWorks. While this was fine for the type of details

pictured it was a laborious process which had me looking for a 

better solution for producing a complete framing model. This led

to the purchase of Home Designer Pro. Now while Pro was

probably all the program I really needed for this project Chief

kept bombarding me with offers to upgrade to Chief Premier

until finally in a moment of weakness I caved in and bought the

whole enchilada. And that in a nutshell is how I arrived here.