Expert: Dan Griffin - 12/23/2007

Question
QUESTION: i have a triple header in my living room all the other ceiling beams are tied into
it  the span is 12 feet by 18 feet my sheetrock keeps on cracking do i need a
microlamb or steel fitch plate or something

ANSWER: You lost me.

I would call what you term a header a support beam.  The ceiling is being carried by joists.

I think you are telling me that your beam is a tripled dimension lumber beam, though you never gave the dimensions (2x6/2x8/2x10/2x12). I think you are telling me that your ceiling joists are joining the beam in plane rather than resting on top of it.  Are the joists toenailed to the beam or are they in joist hangers or bearing on a ledger band?  Is there a second story above? How long is the beam?  How are the ends being carried?  YOu did tell be the span is 12' by 18', but I don't understand the statement.  To some degree it doesn't matter because you said the drywall cracks which indicates that there is excessive movement, though you don't indicate that there is creaking or noise.  You've not indicated the existing ceiling height.

Replacing the beam with an appropriately sized LVL, steel beam, or flitch beam will require shoring the joists on each side, cutting out the existing ceiling, unpinning the joists, getting the old beam out, installing new, and closing everything back up.  This is not a casual project.
I would be uncomfortable designing the new beam without being able to see the conditions and I suggest you contact a local structural engineer if you intend to proceed with the project.

If it is a cosmetic problem only, I might be able to offer some alternative thoughts that are totally subject to your taste.  You could establish a cut completely across the room at the girder line in the drywall.  This cut can be finished with a drywall expansion joint like those made by Trim Tex:  <http://www.trim-tex.com/productsindex.htm>  Look at expansion joint and reveal bead.  Please look through their art gallery for ideas.  You could create a pattern of these joints across the ceiling to disguise the one you need at the beam.  You could add a beam under your problem and box it in like a coffered ceiling with other coffers without beams.

Let me know if I can help more.

---------- FOLLOW-UP ----------

QUESTION: i have a ranch, the ceilings are 8 foot high the carrying beam is 13 foot the
ceiling has 2x6 ceiling joists tied into 2x12 flush header they all have tecos
also there are 2x4's that go up into the ceiling they look like trusses if i use lvl
what size

Answer
I answered this once, but it obviously waslost.

Your 8 foot ceilings make false beams too low.
I have no earthly idea what tecos might be.

I guess you are telling me that there is not a second floor.  You've never told me how much load is bearing on your beam.  Half of the square footage on each side of the beam bears on it.  I really don't understand what you are telling me about 2x4 going up into the ceiling.  Perhaps you have a site built truss to carry the load, but what happened to the triple header?  My preliminary calculations would indicate that tripled 2x12 spanning 13 feet are more than adequate to carry the contributory load of 16 foot joists on each side assuming they carry dead load only of 10#/SF.  This figure assumes that there are no storage and no roof loads being carried by this beam or any of the joists.  The fact that the joists don't tie your outside walls together indicates something very strange.  Is this original construction? or has a wall been removed and someone did this to carry the joist tails?  If the joists are not spiked together to complete the bottom chord of a triangle, there is far too much pressure on the outside walls.  If this is what happened, it really sounds as if the work was done wrong.

We are just not communicating well on this issue.  I would recommend that you seek the advice of someone knowledgeable that can physically see  the situation or you will need to be much more specific about the condition.

Is it a cut roof or truss?
Is it a hip roof, gable roof, or other?
Is this a slab, a crawl, or basement?  If crawl or basement, is there a bearing wall/girder/beam?  What dimension and material is this beam?
If there are floor joists, the roof joists will go exactly the same direction.  These joists must be tied across the structure, both at the floor line and the ceiling line.
How wide is the house?  Joists normally travel half the width.
Is there an attic?
Is there storage on the ceiling joists?
Does anything about the roof bear on the joists or your beam?
What is carrying each end of your beam?  It must be bearing on something.