On Feb 13, 9:07*am, Jeff B wrote:
In the middle of my kitchen reno and while working in my attic, I
discovered that 1 or 2 full sheets of drywall in my living room are
sagging badly. *Apparently the construction adhesive used 30 yrs ago
simply dried up and lost its hold. *Since they used nails not screws
in the 1970s to attach the drywall to the rafters, there wasn't much
to keep it up. *At the lowest spot, the gap between the drywall and
rafter was about 3/4"!! *From inside the attic, I could slide 1/2 my
hand into the gap! *I figured the whole thing would collapse from its
own weight any minute. *I raced to HD and propped it up with a bunch
of 2x4s. * My living room looks like a circus tent.

Getting it supported was step 1. *I now need to figure out step
2...repair. *Replacing all of that ceiling drywall is NOT the
preferred option. *My attic has about 18" of loose, powdery, blown-in
insulation. *Moving that stuff around is a nasty job. *I don't believe
the drywall is cracked anywhere. *It simply sagged as a full sheet (or
2 sheets). * I'm hoping that getting it flush to the rafters with the
2x4s and then using LOTS of drywall screws will keep it up there for
another 20 years. *With the loose insulation, getting adhesive in the
gap before screwing up will be difficult if not impossible.

Anyone have experience dealing with this problem?

--Jeff

This is 1/2" DW. There is no moisture problem and the adhesive
failed...not the paper. The backing is intact and the adhesive is
brittle and crumble-y. I found the same thing when I removed soffits
and installed small pieces of drywall in my kitchen as part of my
reno. This is a split foyer house so most of the living space is
upstairs. With attics getting to 125F in the summer (even with a
gable fan), its no wonder that after 30 years, it just lost its
strength.

And as far as warning signs from below, I have to admit that there
were some I didn't pay attention to. I thought fresh nail pops were
due to vibration from wood floor installation in the kitchen plus me
moving around the attic doing electrical work over the kitchen. I
kept saying to myself "Its minor and I'll spackle it later". I now
see hairline cracks in the crown molding along the wall and tape seams
showing where they didn't before as it began to sag. In hindsight, it
was getting worse by the day! I think I had somewhere between 2
seconds and 2 weeks before it collapsed under it own weight. It was
sheer luck that I noticed it while doing some recessed lighting work
in the attic outside the kitchen area. Lucky me and a big lesson
learned.