Drywall is the standard wall and ceiling covering for most residential construction. Sturdy and inexpensive, drywall is easy to work with, and needs only screws or nails, tape, and joint compound. But drywall does need to be installed on ceilings and walls in a certain pattern to prevent cracking and ensure solid construction. Learn about drywall, fastener, and taping patterns for ceilings and walls.
Ceiling Drywall Layout
On small ceilings, a basic grid-style pattern with evenly spaced seams will work. Small bathrooms, for example, may only need three or four sheets of drywall, so a grid pattern is sufficient.
For most ceilings, though, it's best to stagger the seams between the sheets. This creates a more random pattern and will help prevent potential cracks from continuing across the entire length or width of the ceiling.
Lay the drywall sheets perpendicular to the ceiling joists. The goal is to never have an edge of drywall hanging in the air. So, with the perpendicular pattern, the long edges of the drywall will always have an attachment point on the joists. The short edges of the drywall will need to land squarely on joists, so cut down the boards accordingly or use long 16-foot sheets of drywall that can span from wall to wall.
Wall Drywall Layout
When laying out drywall on walls, you can choose to lay the sheets either vertically or horizontally. The preference is usually to lay the sheets horizontally: that is, 8 feet across and 4 feet up and down. As with the ceiling drywall, this ensures that long edges will always have an attachment point.
Professional drywall installers consider horizontal placement to be a stronger form of installation. Start with the top row of drywall sheets and butt them up against the ceiling. Then, add the lower row of drywall sheets. This row will usually need to be cut down a few inches.
Drywall Fastener Spacing
With a cordless drill and coarse thread 1-5/8-inch drywall screws, drive a screw every 8 inches along the entire perimeter of the drywall sheets.
Also, drive screws in the center of the sheets where they rest on studs. Studs typically run every 16 inches on-center.
Drywall Tape Layout
Tape all drywall seams. Use fiberglass mesh tape or paper tape to tape flat seams.
Inside and outside corners can be taped with regular paper tape. However, most drywall installers use the metal bead for inside and outside corners, or even metal-backed paper tape for inside corners.
Placing Electrical Boxes in Drywall
There are two ways to mark and cut out electrical boxes for light switch boxes and electrical receptacles: measuring and cutting ahead of time or using a placement tool.
With the first method, use a tape measure to find the positions of the boxes in the wall. Transfer those measurements to the drywall sheet and cut accordingly. This can be a frustrating process, though, as the hole is often misaligned. Yet practice and careful measuring will usually eliminate most errors.
The second method is with a placement tool. A plastic insert with a pair of strong magnets is placed inside the box. After placement, the drywall sheet is put up but not installed. The companion device, with a second pair of magnets, locates the hidden section. Mark the outline with a pencil, then cut out the hole with a hand saw, jigsaw, or rotary cutting tool.
Joint Sanding Drywall
Apply joint compound to all taped areas and any depressions, scratches, dents, and screw holes.
First, smooth on the joint compound (also known as mud) to the joints with a medium-sized taping knife. Then, feather out the mud with a large knife. After this first coat has dried and hardened, apply a second coat.
Smooth the joint compound over all drywall screw divots (holes), too. Apply the joint compound as minimally as possible to fill the joint. The more mud you apply, the more you have to sand down later.
Sections of Drywall to Sand
With a hand-held and pole-mounted drywall sanding tool, sand down all areas covered in joint compound. Sand lengthwise in the direction of the seam.
Coarser grit sandpaper should be used in the first phase to bring down the rough areas. Avoid the temptation to use very coarse grit sandpaper; this will abrade the drywall paper surface. Follow up with lighter grit sandpaper in the second sanding.