Why Tape Fails
Drywall tape needs three things to bond properly, as CertainTeed notes in their finishing instructions: a wet bed coat of mud, firm pressure to embed the tape, and time to dry before the next coat. Skip any of these and you're setting up future failure.
Fixing Bubbled Tape
For small bubbles where the tape is still attached on both sides, you might be able to salvage the existing tape. Might.
Score the bubble with a utility knife in an X pattern. Press down firmly on each flap to try to re-embed it. If the tape lays flat and feels solid, cover with a thin coat of mud and proceed with normal finishing.
More often, the bubble is a symptom of larger adhesion failure. If the tape feels loose when you press on areas around the bubble, or if the bubble immediately pops back up after pressing, the tape needs to come out.
Replacing Failed Tape
For peeling tape or extensive bubbling, the only real fix is replacement. Trying to glue down failed tape just delays the inevitable.
Paper Tape vs Mesh Tape for Repairs
Mesh tape is tempting for repairs because it's self-adhesive and easier to apply. You just stick it on and mud over it. No wet bed coat needed.
The problem is that mesh tape is weaker in tension than paper tape. For ceiling repairs or areas prone to movement, mesh tape is more likely to fail. The ceiling seam I repaired originally had mesh tape, which contributed to its failure.
Uncle Cliff's rule, which has served me well: paper tape for flat seams and ceilings, mesh tape only for inside corners where the flexibility is actually helpful. For repairs, default to paper tape.
That said, if the original installation used mesh tape and it's only failed in one small area, matching with mesh tape is fine. Just don't upgrade a mesh installation to paper in spots since the different flexibility can cause problems at the transition.
Preventing Future Tape Failure
If you're doing new work or extensive repairs, set yourself up for success:
Proper bed coat every time. No shortcuts. Spread the mud, lay the tape, embed it firmly. If you don't see mud squeezing out, add more and try again.
Let it dry. Seriously. Overnight for regular mud. This is the step that gets skipped most often, and it's probably the most important.
Climate matters. Don't tape in very humid conditions or when temperatures are below 50 degrees. Both affect curing and can compromise the bond.
Pre-fill gaps. If your drywall seams have gaps larger than 1/8 inch, fill them with compound and let it dry before taping. Tape bridging big gaps is more likely to fail.