is my drywall failing?

[iron]

4 years ago, we skimcoated our drywall (walls and ceiling) and then applied a minimal texture on the final product. shortly after that, i added some insulation to the attic (i forget the number now, but feel like it was 15" deep combined blown-in pink stuff + blown-in cellulose).

nothing noticeable until just recently while laying on my daughter's floor, i noticed dimples. they come in pairs in what looks to me like the edge of a full sheet of gypsum board. the original drywall is 1979 and was nailed up. from the drywall i've removed from the house, the nails had smallish heads and were slightly rusted. i think the indentation is >1/16", but hard to tell. i don't see any signs of taping failure or anything like that.

thoughts?
anyone else encounter this before?

i know old drywall doesn't have the same load carrying capacity as new stuff from a deflection standpoint. i can't really imagine nails punching through is a common concern because i've never seen anything about it. but, that probably is because sheets are nailed/screwed up per spec. i am wondering if this particular sheet is shy a couple nails...

 

[MTY]

I suppose the drywall could be dropping down. but most likely those nails were deeply set and not properly covered. Take an ice pick an pierce between two of the dimples. If you go slow and easy you should be able to feel if there is a gap between the dry wall and the wood it is screwed to. No gap, no problem. The bigger the gap, the bigger the problem.

 

[iron]

depressions were not there 4 years ago. we skimmed over it. perfectly smooth (at least no obvious nail depressions)

 

[EatenByLimestone]

Is your insulation still dry?

 

[SpaceBus]

Is your insulation still dry?

My first question as well.

 

[BigJ273]

Is the distance between the dimples symmetrical? If it is, I would bet someone was throwing something up there to hit the ceiling. ???

 

[sloeffle]

I would bet someone was throwing something up there to hit the ceiling. ???

That is what my money would be on.

 

[iron]

my attic hatch is sealed off, so i can't get up there to look, but i have to think that it's dry up there. it would be an odd spot for a water leakage given the roof. shingles only 5 years old.

no one is throwing anything up there. daughter just turned 3.

 

[redmanlcs]

everywhere I look on other forums say that its either drywall that has fasteners that are starting to fail, or not holding any longer,,, or water damage in attic aka wet insulation or rotten beams. Just what I have found..

 

[Hogwildz]

If the fasteners were failing, they typically drop down and the heads start pushing through the drywall. If the drywall has too much weight from insulation on top of it, it may be sagging around the nail heads, which will cause those indents. That is my guess.

 

[peakbagger]

The only way you are going to know for sure is cut out a section and diagnose it. I have heard of defective drywall with voids right from the factory but if it lines up with nails or framing then its a local condition.

 

[iron]

i pressed up on the sheet last night. didn't get it to move, but heard some very minor cracks. i guess i'll monitor for now and if it gets worse, i'll add a bunch of screws and then patch and texture.

 

[Seasoned Oak]

i pressed up on the sheet last night. didn't get it to move, but heard some very minor cracks. i guess i'll monitor for now and if it gets worse, i'll add a bunch of screws and then patch and texture.

That is what i would do. And when you add the screws just counter sink them barely below the surfac cuz once you break the paper all the holding strength is gone.

 

[bloyet03]

One thing that stood out to me is you said nails, not screws. Last time I seen drywall coming down and it had nails, it pulled the nails out. if you pushed up right in line with the dimples and it didn't move, I don't think its coming down like said. You should have seen nail heads popping through if it was coming down. (assuming you pushed with a decent amount of force) might also get to the edge of the room and sight along the ceiling. If its bowing down, you'll see it.

but, I'd say most likely you just found some missed nail heads.

 

[iron]

i pushed with enough force that i think it would move the drywall if it had displaced.

i definitely didn't miss these. it's hard to when skim coating.

 

[Seasoned Oak]

i pushed with enough force that i think it would move the drywall if it had displaced.

i definitely didn't miss these. it's hard to when skim coating.

You need at least 3 coats to allow for shrinkage with the mud. If you only did one or 2 that may explain it. When i do joints , it looks and feels good after 2 coats but when you look at it from the side you can still see a small depression.

 

[Highbeam]

You need at least 3 coats to allow for shrinkage with the mud. If you only did one or 2 that may explain it. When i do joints , it looks and feels good after 2 coats but when you look at it from the side you can still see a small depression.

this is probably it.

sheetrock nails are usually ring shank and almostnever pull out since the head is rather weak compared to those rings. In fact, I end up driving them in when I replace Sheetrock since they almost can’t be pulled with a hammer.

 

[iron]

by skim coat, i mean: there was a heavy knockdown texture on our walls and ceilings. we then took a copious amount of mud, rolled it on with a paint roller, and skimmed it down with a squeegee (magic trowel). light sanding, and all done. whatever mud was used in the original hanging of the sheets is probably under 1/8" (minimum) of mud as part of the skim coating and knockdown textures.

 

[billb3]

Those look just like the hammer dimple you're supposed to have if you hammered the nail in just right . Those are the typical dimples you get when nailing sheet rock and rushing the joint compound job. You wouldn't see them until after you painted unless you put a light flat on the ceiling looking for shadows. With screws you had tiny dimples and there was less shrinkage of the joint compound. If you ever had joint compound crack (shrink) from curing too fast or put on too thick you know how much it shrinks.

An 1/8 inch of skim coat on 3/8 drywall is a bit of weight as is many pounds of loose fill insulation. Add a vapo barrier ( or lack of one) problem into the mix and your drywall might be sagging. Take a long straight edge to the ceiling and see if it is not as flat as it should be.