Plasterboard is a sheet material that is commonly used to line internal stud walls.
The strong, highly fire-resistant sheets are made up of a gypsum core encased in heavy-duty lining paper.
Hanging plasterboard isn’t hard to do DIY, relying mostly on accurate cutting, but getting the joints smooth is a skilled job. A rough finish on the joints will show through even when the walls are painted.
We show you how to cut and hang plasterboard sheets step by step and also finish the joints.
If you want to call in a plasterer for the joints, it will take them a day and cost about $400 for an average-sized room.
DIY TIP Use a utility knife to score the paper and the gypsum will break along the line of the cut.
CUTTING TIP Another pair of hands is helpful to support the plasterboard sheet while you’re cutting.
Here are the basics of hanging plasterboard on a stud wall.
SCORE the front paper, then snap and fold open the sheet.
CUT through the paper on the back. Use a keyhole saw for short cuts, like a switch plate hole, and a coarse-tooth saw for cuts around doors.
LAY the sheets flat on the floor to do intricate layouts so it is easier to use chalklines and straightedges.
MAKE openings for existing doors and windows before hanging other sheets. Jambs and insulation will prevent cutting sheets in position, so cut these on the floor.
SAVE waste by cutting to length before cutting to width.
USE 3600 or 4200mm long sheets instead of 2400mm. The leftover pieces will be longer and more useful, with fewer joints to tape.
POSITION the cut sheets to minimise the number of joints, especially hard-to-tape butt joints.
After cutting the plasterboard hang the sheets
Secure plasterboard by applying stud adhesive to the wall framework in daubs 30mm wide and 12mm thick, spaced 250mm apart and 250mm away from any nailed or screwed edge. Position each sheet and secure along the recessed edges at each stud, then at the ends every 150mm
using plasterboard screws or nails.
Cut the plasterboard
Lean the stack of plasterboard sheets at a slight angle against the last wall to be covered. Make sure the top edges of the sheets are evenly supported by the stud framing to prevent them from warping.
Mark the length along the top and base of the sheet, then line up the right side of the square with the marks. Starting at the top, score two-thirds of the way down with a utility knife, then finish scoring from the base up.
Lift the sheet away from the stack and position yourself with the scored side facing away. Ensuring the sheet is resting on the floor, knock your knee on the scored line to break the gypsum core so you can fold the sheet open.
Using the utility knife, cut halfway down through the crease on the reverse side of the sheet facing you, finishing the cut from the base up. Steady the top of the sheet with your free hand to hold the two halves together.
Pull the utility knife behind the square to cut sheets to width. Hold the blade against the aluminium tongue, then pierce the lining paper with the tip. Slide the top of the square and the knife along the length of the sheet.
Clear the floor of scraps and screws so you don’t dent the sheet. Lower the sheet close to the floor and snap each cut open with a soft karate punch. Slice through the lining paper along the crease on the underside to finish.
Nail or screw the plasterboard sheets over wall openings when possible, leaving the area above the opening unfastened until you finish cutting. Cut upwards using a saw until the blade hits the timber at the top.
Score the underside of the plasterboard sheet along the top of the door framing. Snap the flap up, then cut through the front lining paper of the plasterboard sheet, following the crease line carefully.