Why is my drywall crumbling?

Asked October 21, 2015, 1:39 PM EDT

I am the original owner of a newly constructed single story, slab on grade home that was built two years ago. About a week ago, I noticed a small bulging spot in the sheetrock just above the baseboard on an interior wall with no plumbing inside it. Pressing on the spot indicated that the drywall was basically delaminated in that area. Further inspection revealed that the drywall in the area (about 6" x 6" from the floor to a few inches above the baseboard) was weak. I cut out that portion of drywall, and it crumbled as I was removing it, but was not stained or wet at all. There was also no mildew odor and no water stains inside the wall. I also checked the carpet tacks on the floor in that area, and they showed no evidence of water or rust.

Could this problem have simply occurred during construction, and I just now noticed it? Perhaps damaged sheetrock was installed in that area? Any other ideas as to what may be the problem? Before repairing the wall, I want to make sure I am not covering up a larger problem.

The drywall everywhere else in the house is perfectly fine to the best of my knowledge.

Thanks so much for your help!


3 Responses

Even though you found no wetness, moisture is still a potential concern to investigate further. It's possible to have wicking occur from the foundation, or hidden condensation at times. I'd be inclined to get a moisture sensor (sonar) or meter and compare moisture readings of that area vs. other areas. If higher, investigate possible sources of cold air spots or wicking.

Another possibility is termite damage. Look for holes and tunnels.

And, as you said, it might have been damaged all along. Or, there could be too much expansion and contraction stress in that spot, if overly nailed onto the bottom plate.

My suggestion is that once moisture and termites are ruled out or corrected, cut out the weak materials and patch with a piece of new drywall.

Thank you so much for the response! I will definitely look into moisture meters. A couple of questions:

1. Would there not be some type of staining or mildew odor if water had wicked into the material? Would the carpet tacks not be rusty if moisture was present in that area at the foundation? Additionally, the drywall on the opposing side of the wall is in perfect condition.

2. This is an interior wall in the middle of the house. Would termites present here, as opposed to an exterior wall? I've always been very careful to keep wood from making contact with the ground outside the house to prevent termites from getting to the house.

Thanks again for your help.

There might not be staining or rust if moisture is from wicking through materials. Could also be it got wet before installation. Point is to check with a sensor or meter to rule out current moisture.

Termites tend to be found in exterior walls since there are more entry avenues, but they can enter via foundation cracks and crawl anywhere, especially in search of moisture.

When you cut out the damage, take a good look inside before you patch the wall.