Drywall, a convenient alternative to wet plaster, consists of (plaster) board between layers of thick paper. Drywall sheets often feature tapered edges so the seams can be finished or taped with joint compound, although it is possible to purchase sheets without tapered edges. Even in tapered sheets, the ends are preserved and left flat.
Drywall sheets are typically available in four different thicknesses: ¼-,3/8- , ½- and 5/8-inch. A standard sheet tends to be 4 feet wide and 8, 10, or 12 feet long, although it is possible (albeit significantly more expensive) to get a panel in a custom length. There are two specialty kinds of drywall available, type X and type MR, that are intended for specific applications.
Type X: This kind of drywall has a higher fire rating and is often used between a house's exterior wall and an attachment, such as a garage.
Type MR: For areas with a high-humidity level, such as bathrooms, MR is a good choice because it is moisture resistant.
Depending on multiple factors, such as where the drywall is installed, there are several fastener options. Nails, screws, and panel adhesives are all commonly used, and each offers its own advantages.
If attempting to mount drywall to wood, nails are the appropriate choice of fastener. In order to protect the paper on a drywall sheet and minimize the amount of puncturing, nails for drywall have ringed shanks and a relatively large head. Because nails can sometimes pop back out, using a second nail 2-inch from the first is suggested. For ½-inch thick sheet of drywall use a 1 ¼-inch nail. for a 5/8-inch thick sheet of drywall try a 1 1/3-inch nail.
Screws can be used when mounting drywall to wood or metal, and must be used when attaching drywall to metal studs. Unlike nails, they do not pop up through the surface and tend to provide a more secure hold, but are more expensive. Generally, fewer screws are needed when compared to the amount of nails needed for the same application. A 1 ¼ screw is appropriate for any sheet thickness.
To adhere new drywall to an older sheet, plaster, or panel, adhesive is a good choice, but when mounting on a ceiling using reinforcement (like nails or screws) is often recommended. A tube of adhesive is enough for 100 square feet of drywall.
Joint Tape and Compound
Using joint tape and compound is the last step in fastening drywall, and gives the whole project a nice finish. If a project is large, using paper take is recommended as fiberglass mesh tape is generally intended for small scale patch work. After applying compound under the tape, make sure to squeeze out the extra compound. Generally, three coats of compound are needed to finish a joint.
Attaching to Drywall
Because drywall is not meant to support large amounts of weight, carefully consider how to attach heavy items, such as mirrors and picture frames. Fortunately, there are many that make hanging heavier items feasible without damaging the drywall panel.