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I have 24 foot span on a 11.5 inch by 3.5 inch laminated beam, in a house I purchased. It also has a right angle “header”type beam intersecting at 8 feet from one end. Do I need to add 0, 1 or 2 support columns underneath. There is a living floor above. The beam is on the main house centerline.
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Details Doug, Details.
What kind of beam?
Are there roof loads being transmitted to it, or is it a truss roof?
If it is an existing house, why do you want to put support columns under it in the first place?
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Hi, there! This is Suzi, Doug's wife. Thank you so much for responding. My husband had to leave for a while and I'll try to
explain this as simply as I can.
It is not a truss roof.
This is a 10 year old "open concept" house. The house has one section
18 feet wide with 3 levels, next to a center, 4-level section with a separate roof. The living room is 26 feet wide, overlapping the
two sections on the second level. There is an open staircase/atrium to the lower level 20 x 16. The living room is an "L" 33' from front
to back with the atrium on two sides. I would like to close off the
open atriums with walls. I have no idea what is holding
up the front section of the side wall of the center section with 4
levels and a roof, which has started to dip at that point.
We think the beam is is a parallel lam -- many thin layers (30 or so) running parallel to the length. This visible beam, was covered in drywall, traveled the width of the living room, into the center
section of the house. A 4.5" beam meets it at a 90 degree angle where the 2 sections of the house meet. It is also visible. We don't know what kind of beam that one is. We have removed some of the corner bead and drywall. From the bottom we see a 2 x 4 with plywood attached to the sides. It is not apparent how the two beams are attached -- no joist hanger or metal that we can see and they no longer appear to be touching each other (3/8 to 1/2" apart).
We have noticed that the beam, especially at the intersection of
the two hanging beams has been cracking and the floor above is
terribly out of level. There is a "strongback" over the beam on the third floor which was made into a long ackward platform along the
bedroom and sitting room wall. Now that we have started to work in that area, we noticed that the floor shakes -- I put a two liter bottle of water on the floor and it wiggles when I walk (100 lbs of me) The drywall ceiling in the sitting room -- the center section -- where the strong back continues (directly above the large open area below) -- is cracking.
The former homeowner was doing the renovations but left before
completing them. We have been trying to finish ourselves.
We have removed a 6" section below the living room (another open area with a beam) We discovered that there is a metal "I" beam supporting the floor above with two 3" metal posts 13' 4" apart, starting 5 feet away from the outside wall. Also, the side of the center section of the house, a beam of 3, 2 x 12's, rests on this "I" beam. There is no support under this section of the "I" beam and it is out of level
7/l6" in 4'. It is 9' from the first post and 4' from the second. I was planning to put a pole under this
part of the "I" beam. (Neither one of us welds) and also one under
the beam of 3, 2 x 12's.
We have not moved any furniture into the house yet. I am a
packrat, with TONS of stuff. We want to be sure that we don't
have major problems when we move in.
The third floor will have a second mastersuite, living room, bath,
kitchen, dining room as well as my studios. The fourth floor is
heated and airconditioned and will be a huge walk-in closet and
storage area.
Any suggestions???
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Suzi,
You took so much time trying to describe the details but, I'm sorry, I couldn't follow your description. Maybe you could scan a sketch or photo and attach it. You can get all sorts of opinions from who knows who on this site but, its sounds like eventually a visit from an engineer may get your question answered.
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Darrell,
Thanks for the suggestion. We will work on a sketch or drawing and attach it to a post...
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Suzi,
Do you know how long ago the work was done? If within a few months, I'd think about putting up a temporary means of support until you can get it shored up permanently. It seems like there is a lot of weight above a weakly supported area.
A tip: take a string, and clamp it to the sides of the beam flush with the bottom of it on both ends, stretched along the bottom tightly, and you can see how much deflection (sag) the beam now has, and where it is concentrated. If this sag corresponds to the floor above (which I take is the one out of level) then your (implied) fears are well-founded.
I am still confused about the house, but can sort of picture it, and I am guessing that the beam/header area is not sufficiently supported to carry as much weight as is being applied to it. I don't generally like these types of connections without posts under them.
Incidentally, you don't need to weld to put a support post under an I-beam. You can get lally columns with an adjustable screw type thing that will support and raise the sagging beams, and if you want to attach it permanently, you can drill holes on each side of the bottom of the "I" and bolt it on. You will want to see what is underneath this on the next lower level(s) before you add to the problem!
Hope to see some pics to help more.
MD
*Without being cruel and keeping it simple, please spend a few bucks and bring in a structural engineer.If you can't describe it in 50 words or less, in a manner that all can understand, it's too complicated for you to do on your own.sorry Gabe
*It sounds like this is too complicated for you to trust the expertise of a bunch of guys on the internet. What needs to be done is to add up all the loads this beam is supporting and check the manuracturer's tables to see how long a span you can have.Have an engineer look at it. Worth the money.
*Doug and Suzi - I'm with Gabe in suggesting you have a professional come out and look at it. Particularly so since it has a stick framed roof. We don't know exactly how the roof was framed, the exact beam spans, the manufacturer of the beam, (Different beams have different strength charachteristics) how the floor above is framed, etc. There are just too many questions to give a reasonably accurate answer. I can tell you from experience that there's no way a 12" beam will span 24' and carry any amount of weight. It will barely carry itself at that span. Best of luck, whatever happens.........
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Thanks all for your advice and support. We are having a steel erector company install 3 posts on the first floor, under the steel I beam and the 90 3-12inch beam at 90 degrees. Over this, they are welding a steel plate on the I beam to extend it out 2 inches, to be under the 24 foot laminated beam supporting the 3rd floor.. Steel columns will be welded to the steel beam/plates, over the original base footers, and along the column span. 3 columns well be installed here as well... Actually all very reasonably priced....
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Did you ever get that drawing?
*is this an engineered solution?
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I have 24 foot span on a 11.5 inch by 3.5 inch laminated beam, in a house I purchased. It also has a right angle "header"type beam intersecting at 8 feet from one end. Do I need to add 0, 1 or 2 support columns underneath. There is a living floor above. The beam is on the main house centerline.