What can cause drywall tape failure?

[Shrek]

Hi, About 2.5 years ago, A contractor finished off the attatic space in my home. To run plumbing, an access hole was created in the living room ceiling on the 1st level. The access hole was repaired using new drywall (about 12 quare feet) and finsihed and painted.

Fast forward 2.5 years latter and almost overnight, the drywall tape on 3 sides are delamanating. As far as I can tell this is not due to any water damage from leaks.

My questions are.

1) What could cause this and why did t take 2.5 years for the tape joints to fail?

[tomcas]

Just a guess but heat and moisture are probably factors. Why it took 2.5 years is because it was not done correctly in the first place. What do you mean by delaminating? If it is embedded in drywall compound as it should be, the compound itself would have to disintegrate in order for the tape to fail.

[Art]

Is it a plastic like tape in corners? I've had trouble with that too in my house. Plastic changes with tenperature differently than paper is probably the problem and eventually gets loose.

[Shrek]