Dear James: I am ready to put up drywall in an at-home office for my business. I have put up drywall before to divide one large bedroom into two, but the joints look bad. This room must look better since clients will visit. What should I do differently this time? -- Charlotte K.
Dear Charlotte: The joints between two pieces of drywall are probably the most important factors when hanging drywall. If at all possible, you might want to practice on two "experimental" pieces before you start on the real wall, especially since this room has to look professional.
Your last job probably looks bad because you did not use thin enough coats of drywall compound on the joints. A key element to a good-looking drywall joint is many thin layers of compound. Applying multiple thin coats is a process that takes more time and creates more dust, but it is worth doing.
Your choice of tape may have also affected the look of the joints. There are two kinds of tape you can use to secure the drywall in place. Paper tape is the stronger of the two but can wrinkle and trap pockets of air, which will look messy. Fiberglass mesh tape is already sticky and can be applied directly to the drywall. If you decide to use self-adhesive fiberglass tape, just take the backing off and apply the tape over the joint. If you are using paper tape you first need to apply a thin bed of joint compound.
There are also two main types of joint compound. The first type, all-purpose compound, comes in both powdered and premixed forms. Used for any type of taping jobs, this type of compound takes a day or more to dry and can sometimes shrink as the water evaporates from it.
The second type is setting-compound, which is only available in a powdered form. It sets up through a chemical reaction like cement instead of drying, so it cannot be premixed. This compound sets hard and doesn't shrink. Most professionals use this type for filling holes and wide joints. This compound is also recommended for use with the fiberglass mesh tape.
If you chose standard paper tape, take a small knife and apply compound to the joint. Smooth the tape into the compound and then work it from the middle outward. While the joint compound is still wet, put another coat of compound over the tape. Use only enough compound to cover the tape, which should still be visible through the compound.
If you use fiberglass mesh tape, cut a length of tape, place it over the joint first and press the tape firmly down across both pieces of drywall. Next apply the compound over it. Let the compound dry thoroughly overnight.
After the joint compound has dried, use sandpaper to eliminate any irregularities from the wall. Again, you will have to re-coat the joint with the compound. What you are trying to accomplish now is a feathered look, so the joint is not noticeable when finished and painted. Most likely, you will have to re-coat the joint a few times, but remember to use thin coats. Also beware of getting the middle of the joint too high or it will show after the wall has been painted.
Don't rush to paint the wall. Give the new drywall joint time to completely dry or the paint may absorb into it. Two days is generally long enough. It will probably take two thin coats of paint to make the surface texture of the rest of the wall.
Send your questions to Here's How, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit www.dulley.com.