Drywall is a relatively easy material to install on a frame to give a room a uniform look. The areas where the drywall panels come together, known as the joints, have to be finished before the drywall can be painted. This finishing process requires drywall tape to be applied to the joints to provide a seam that can be painted over to create a uniform surface. Standard drywall tape is made of paper or mesh (which need to be attached with drywall plaster).
Self-adhesive drywall tape has an adhesive backing. Normal drywall tape is a single strand of paper or fibreglass mesh with no adhesive. A coat of plaster has to be put down, then the tape applied to the plaster, and another layer put over the tape. When the plaster dries, it's sanded down till the wall is uniform and then painted over. With self-adhesive tape, there's no need for a base coat of plaster. The tape is simply unrolled and the paper backing it peeled off as the tape is applied directly to the drywall joint. To smooth the tape as it's applied, a putty knife is run down from the top to the bottom to make sure the adhesive is properly sealed.
Advantages and Disadvantages
The advantage of self-adhesive tape is that it doesn't need a base layer of plaster. This saves a great deal of time and even money, since less plaster has to be used to achieve the final result. Self-adhesive tape is also more difficult to apply, though, since it has to be put on straight the first time. Attempting to remove the tape will damage the drywall, and may require that both the panel and the tape be replaced. Like many other choices in the building and remodelling process, the type of tape used should be dictated by the job, rather than by what's easier.