Drywall Cracking
Drywall Cracking
(OP)
Does anyone have literature on causes of drywall cracking at exterior steel stud walls?
I have a building that was designed 5 years ago; they have over 180 minor drywall cracks throughout the structure. The stud deflection under max. wind load for the area is h/400. Most (but not all) cracks occur at window corners and stairstep up following the drywall joints. Most of the cracks are on the exterior walls. Some even occur in drywall that was installed on top of plywood shear walls.
No cracking is noted in the stucco on the opposite side, no cracking is seen in the stem walls. Cracks have been patched numerous times, but keep re-occurring. Expansion joints have been installed during the on-going repair process.
The owner, architect... are frustrated that the repairs aren't holding, and they insist the cracking must be due to stud movement. Since the stucco isn't cracking, I am having a tough time agreeing with this. I suspect sub-standard workmanship and poor patches, but can't back it up.
Any help in finding causes for this type of cracking would be appreciated.
I have a building that was designed 5 years ago; they have over 180 minor drywall cracks throughout the structure. The stud deflection under max. wind load for the area is h/400. Most (but not all) cracks occur at window corners and stairstep up following the drywall joints. Most of the cracks are on the exterior walls. Some even occur in drywall that was installed on top of plywood shear walls.
No cracking is noted in the stucco on the opposite side, no cracking is seen in the stem walls. Cracks have been patched numerous times, but keep re-occurring. Expansion joints have been installed during the on-going repair process.
The owner, architect... are frustrated that the repairs aren't holding, and they insist the cracking must be due to stud movement. Since the stucco isn't cracking, I am having a tough time agreeing with this. I suspect sub-standard workmanship and poor patches, but can't back it up.
Any help in finding causes for this type of cracking would be appreciated.






RE: Drywall Cracking
Regards,
Andrew Kester, PE
Florida
akester74@ "google" mail.com
RE: Drywall Cracking
Dik
RE: Drywall Cracking
Look more closely at the stucco. It is sometimes difficult to find stucco cracks, particularly if an elastomeric coating was placed on it. There are likely cracks there. They too, are caused by drying shrinkage and, fairly often, improper lath placement.
I doubt the cracks in the drywall are from structural movement. If that were occurring, you would see cracks at midwall or other areas not associated with drying shrinkage.
In short, the studs probably have nothing to do with it.
What is the use of the building? Is there any chance that the use of the building creates humidity spikes? Is the HVAC system dehumidifying too much?
RE: Drywall Cracking
RE: Drywall Cracking
RE: Drywall Cracking
RE: Drywall Cracking
BA
RE: Drywall Cracking
2) check that slab movement relative to the wall isn't an issue (where the slab is not integral to whatever supports the studs.)
3) fix the cracks at corners of the windows and doors using zinc expansion joints - they are very thin and allow seasonal movement without cracks appearing - I just did this to my entire 40 year old house, and it is common practice with commercial buildings in areas with expansive soils.
RE: Drywall Cracking
Just a thought based on general properties.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: Drywall Cracking
The architect on the project attributed it to lack of joints and humidity because I think the mechancial systems took an extra long time to get into place. Plus it is Florida where things are really muggy to begin with.
I had another project once where the dry wall on a stud wall directing under a floor beam near an expansion joint cracked. I attributed this to the fact that the beam was moving horizontally and the cold-formed steel studs and track were ridgidly connected to the beam. Here we got of because our specs called for slip tracks when mounting to the bottom of a beam. The problem was solved apparently by not detaching the tracks but by using closer joint spacing for the repair.
John Southard, M.S., P.E.
http://www.pdhlibrary.com
RE: Drywall Cracking
For more information: this is two single story office buildings. I am trying to get information on the weather when this was originally installed so we can see if there were any extreame weather issues at the time.
They brought in a new drywall repair guy last week. He patched one section- and by the next morning, it was cracked again. No wind that night and the temp differential was only 30 degrees. Doesn't seem like enough to cause this cracking.
I will follow up with some of the other suggestions.
Thanks