What Drywall Is
Drywall, also called gypsum board or plasterboard, is a panel with a gypsum core between layers of paper. It is the standard wall and ceiling covering in most modern homes. Panels commonly come 4 feet wide and in several lengths, and in different thicknesses and types, including moisture-resistant and fire-rated versions. The right type for a given room depends on local code and the situation, so check the plans or ask at the supplier.
This article is a general overview of how panels are cut and fastened. Taping and finishing the joints is a separate step and is covered elsewhere on this site.
Tools for Cutting
Utility knife. Most straight cuts are made by scoring. You hold a straightedge or T-square on the line, run a sharp knife through the paper face and into the core, then snap the panel back along the score and cut the back paper from the other side. Blades dull quickly on gypsum, so swapping in a fresh one improves control and reduces the pressure you need.
Drywall T-square. A 4-foot square with a long blade that matches the sheet width. It keeps cuts square and speeds up marking.
Tape measure and pencil. Measure each piece to fit rather than assuming a wall is the nominal size. Subtract a small amount if the manufacturer or plan recommends a slight gap at edges.
Drywall saw or jab saw. A narrow, pointed saw for cutouts around outlets, switches, pipes and light boxes. You start the cut by poking the point through the board and sawing along the marked line.
Rotary cutout tool. A small power tool with a bit that routes openings for electrical boxes. It is quick but easy to overcut, and it creates dust.
Rasp or sanding block. For smoothing rough edges so panels butt together without gaps.
Tools for Fastening
Drywall screws are the common choice because they hold better than nails and are less likely to pop out. They are designed for the job, which is why drywall screws and wood screws are not interchangeable. Screws are driven with:
- A drywall screw gun with an adjustable depth-setting nose that stops the screw just below the surface.
- A cordless drill or driver with a depth-setting bit, or careful control of the clutch.
Screw spacing, length and pattern depend on the panel thickness, the framing, and the local code or manufacturer’s instructions. Spacing of around 12 to 16 inches on walls and a little closer on ceilings is a common range, but check the specific guidance for your job.
A dimple, not a tear. The screw head should sit slightly below the paper surface without breaking the paper. A torn paper face holds poorly, so back the screw out and drive another a short distance away. Screws that are set too deep or too shallow both cause problems at the finishing stage.
Laying Out the Job
Good layout reduces the number of joints to finish, since seams take time. A few general ideas:
- Panels are often hung horizontally on walls, which shortens joints, though vertical hanging is also used.
- Ceilings are typically done first, then walls.
- Stagger the end joints so they don’t line up in one long seam.
- Plan joints to fall on framing members, where the panel can be fastened on both sides.
- Edges that meet at corners need fastening patterns that avoid forcing the corner out of alignment.
A stud finder or a chalk line helps mark framing locations on the panel face, so the screws land on wood and not just in air. Marking framing lines before the panel is up saves hunting for them afterward. The framing itself should be checked for flatness first, and a straightedge laid across the studs shows high or low spots that may need fixing.
Handling Heavy Panels
Drywall is heavy and awkward. A standard 4 by 8 foot sheet of half-inch board is a two-person job for many people, and ceilings are harder. A panel lift, available to rent, holds a sheet against the ceiling while you fasten it. Carry panels on edge, keep fingers clear when setting them down, and watch for overhead hazards. Back strain is among the more common injuries on drywall jobs, so plan the route and use help.
Working Around Openings and Obstacles
Measure the position of each outlet, switch and pipe from known edges, transfer the position to the panel, and test fit before screwing. Cutting a hole slightly small and enlarging it is safer than cutting it too big. Electrical power should be off whenever you are cutting near boxes or wiring, and you should confirm with a tester.
Safety
Wear safety glasses, because snapping and cutting throw fragments. A dust mask or respirator suited to fine dust helps when cutting and sanding, and keep the area ventilated. Gypsum dust gets everywhere, so seal off doorways and vents where practical. Use a stable ladder or stilts only if you are trained, and avoid working on slippery or cluttered floors. Knife cuts are a common injury, so keep hands behind the blade path and retract the blade when you set it down.
Methods and requirements vary with location and the type of building, so follow the manufacturer’s installation directions and local codes. For fire-rated assemblies, commercial work or structural questions, consult a qualified professional.