help w/cracks

begsb5

the ceiling in my addition has cracks in the tapered joints all the way 18' across the room . the room has a vault w/25'clear span up a 6/12 pitch. i used engineered wood beams for rafters. the butt joints didnt crack. 5/8 sheetrock w/fiber tape. looking for a cause and solution. thanks for any help

AtlanticWBConst.

If you used regular compound (Bucket) and the mesh tape, that could be part of your problem. We see that happening all the time. (Paper tape with Bucket compound)

Another factor....It's now cold weather and heating systems are creating very dry air in homes. If the rafters had some moisture in them and have now dried out and shrunk slightly, that could contribute.
Also, if you attached the sheetrock directly to the I beams, rather than strapping .....
These are just a couple of thoughts that cross my mind right off...

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begsb5

WB,

thanks for the reply!!

do you have any solution that could repair the problem?

AtlanticWBConst.

All I could say is:

Scrape off the areas good, where there are cracks.
Attach additional screws into those factory seam areas, make sure that they are not 'popping-through' and broken the paper of the sheetrock (this could also be part of the problem; 'popped' screws or not enough screws) - Screws should be placed 1"- 1 1/2" away from the seam edge, but no more than that.

Get some durabond 90
Get your self some paper tape (instead of mesh for this one)
Re-tape and coat the cracks (seams) with the durabond.
Finish coat with regular bucket ready-mix compound (It sands easier)

Also:
Do you have rafter vents installed in your rafter cavities?
Do you have additional venting installed in your soffits?
Do you have a ridge vent installed?

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begsb5

i installed the "egg carton" baffels in all the cavities from soffit to ridge.
soffit vents the whole lenth of the soffit 4" wide.
lomanco ridge vent.
thanks again you confirmed my thoughts.

BUT @#$&


i hate mudding sheet rock!!!!

AtlanticWBConst.

Find a taper to do it for cheap.
A job like that: if you cover your furniture with plastic, supply all the materials and do the sanding yourself...it can be done in a day for about $250 or less (dependant on the area you live in)

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begsb5

tried to peel the fiber tape of add it is pulling the paper loose from the drywall. could i just apply the new paper tape and durabond over the exsisting fiber tape and mud to cover the crack. will the durabond adhear to the surface. also i have primed and paint the surface allready as well.

AtlanticWBConst.

You need to remove any loose tape (Fiber or paper)...yes, you can install over the fiber tape, as long as it is not loose...

Yes, the durabond will adhere to the surface.

Only factor about pre-priming and painting the surface and durabonding over that is that, the durabond will take MUCH longer to dry...than on the stated time on the 'bag'...

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begsb5

none of the tape is loose just a crack down the seam.

i was trying to get the fiber tape of the seam. is this not what i need to do. should i just go ahead and apply the durabond with paper tape over the crack and not even try to get any of the existing fiber tape and mud off.
or just live with the cracks

please excuse my ignorace! and bad spelling--

AtlanticWBConst.

BEFORE ANYTHING: Add any additional screws needed. Simply check for proper S/R attachment by smacking the 'bottom' of your fist in an upward thrust and 'pound'....to see of the screws or sheetrock 'move'.

Then:

1.) Mix up some durabond and do a thin skim coat over the mesh tape...THIN (to fill in that 'crack')

2.) Apply paper-tape over the seam as if there were no mesh tape there.

3.) Coat and re-coat as if it were a 'new' sheetrock seam.

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begsb5

more info---the seams are, were finished taped, mudded, primed and painted before the cracks appeared can i still use your last posts instructions

the crack is about as wide as a pencil mark.

thanks again for your insite

AtlanticWBConst.

Yes, we have done this literally thousands of times with good results...

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begsb5

thanks WB!