The extra moisture on bathroom walls requires a special kind of drywall.
You can't use regular drywall to cover a wall that will get unusually wet, such as one surrounding a tub or shower, because moisture will separate the gypsum inside and it will eventually fall off the wall. The drywall manufactured for these locations is covered with green paper, so builders sometimes call it green board or green rock. The gypsum inside green board is treated to resist moisture, and although it is not entirely waterproof, green board will stand up to most bathroom conditions. Installing green board isn't much different than installing regular drywall.
Instructions
1. Install full sheets of green board either vertically or horizontally. Whichever orientation you choose, the vertical edges must bisect a stud face. This bisection will be automatic if the studs have the standard spacing of 16 inches on centers.
2. Cut the green board when you need to fill a space smaller than a full sheet, or you need to trim a full sheet so its edges bisect the studs. Measure the length or width you need with a tape measure and draw a straight line across the face with a straight edge and a pencil. Score the line with a utility knife and snap the sheet along the score. Finish separating the halves by cutting through the paper on the back of the sheet.
3. Cut holes and notches with a drywall saw. Draw the outline on the face of the green board, then push the tip of the saw through the line and cut along it in a back-and-forth motion. Clean off the edges of the cut with a utility knife.
4. Screw the green board to the studs with galvanized drywall screws and a drill. Space them 16 inches apart on walls, 12 inches apart on ceilings and 5 to 8 inches apart along the seams. Keep the screws 3/8 inch away from the edges of the drywall so they get a secure grip and sink the heads of all the screws just past the surface of the drywall to make a small indentation.
5. Tape the seams with fiberglass drywall tape, which is waterproof and less likely to develop bubbles than paper tape. Use a drywall knife to cover the seams with drywall joint compound, lay on the tape and scrape it flat with the knife. Cover all the screw holes with joint compound and scrape it flat. Let the joint compound dry for 12 to 24 hours, or until it all turns a uniform whitish-gray.
6. Recoat the seams and screw holes with joint compound and a paintbrush. Scrape it and let it dry. If you plan to paint the wall, apply a third coat to completely hide the seams.
Related posts
Gypsum board (also called sheetrock or drywall) is a modern alternative to plaster when building walls and ceilings, and is much easier to install. The boards come in 8-by-4-foot sheets of varied...
Green board is a drywall made to resist water penetration, and is used around areas that are more likely to get wet such as sinks and bathtubs. Installation of the green board is not much differen...
The American Society for Testing and Materials (ASTM) produces manuals with standards for all types of building materials and construction techniques. It has many manuals dealing with drywall -- a...
Greenboard is a moisture-resistant form of drywall that's often used for walls in bathrooms and kitchens. Like drywall, it's made with gypsum, but it's treated with oil to help it stand up to mois...
Drywall sheets are fastened to the ceiling joists.Drywalling a ceiling requires some physical strength and stamina to hold the drywall sheets up over your head while you install them, but it's not...
