Drywall Tape Repair
Fixing Loose Paper Tape
Drywall tape repair can be frustrating if you do not understand what is causing the problem. Loose paper tape on the wall joints is often caused by one of two things.
One: The mud was too dry and the moisture evaporated out of the mud before the drywall tape could stick to it. (Note: paper tape will pull moisture out of the mud)
Two: While the person putting on the drywall mud had enough wet mud, after the paper tape was pressed into the first layer of mud, the drywaller wiped the tape too hard with his or her drywall blade, pushing too much mud and moisture out from under the drywall tape. With not enough moisture left in the mud for the tape to bond to, bubbles formed in the tape as the tape dried.
You may not notice the bubbles or ripples until the tape has started to dry, or when you come back to put on the second coat of mud. Drywall tape repair is not usually solved by putting more mud over the bubbled areas. This will not fix it!
To repair loose drywall tape, cut the bubbled tape areas so you can re-apply new mud behind the bubbled areas. If there is a large area of bubbled tape that is in need of drywall seam repair, you may have to pull the original tape off completely and start all over. You will need close to 100% saturation of mud under the tape or bubbles will re-appear.
Ceiling Problems. If your problems are involved with drywall tape coming loose and it is a small area, you may be able to work mud up and under the tape and reset it.
But if it is a larger area, and you see this will be a texture ceiling drywall repair, (which will be covered in the coming re-texturing section) you will have to pull the loose tape down, replace it with new drywall tape, repair the area for texturing and then re-texture the patched area.