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How to Plasterboard a Room — Step-by-Step UK Guide
Complete guide to plasterboarding a room in the UK using dot-and-dab or battens, including cutting boards, taping joints and finishing.
What You'll Need
Tools
- Cordless drill/driver
- Stanley knife (heavy-duty)
- Drywall saw or jab saw
- Tape measure
- Spirit level (1200mm)
- Chalk line
- Plasterboard lifter (foot lever)
- Taping knife (150mm and 250mm)
- Sanding block
- Dust mask and safety goggles
Materials
- Plasterboard — 12.5mm tapered-edge (2400 x 1200mm)
- Drywall adhesive (for dot-and-dab) or battens + screws
- Drywall screws — 32mm
- Jointing tape (paper or self-adhesive)
- Jointing compound (ready-mixed or powder)
- Corner bead (for external corners)
- Internal corner tape
Before You Start
- Check the walls for damp. Do not board over a damp wall — fix the cause first.
- Run any electrical cables or plumbing pipes before boarding. Once the boards are up, routing cables is much harder.
- Use our Plasterboard Calculator for board quantities, Dot and Dab Calculator for adhesive quantities, and Dry Lining Calculator for tape and filler.
- Remove old loose plaster from masonry walls if dot-and-dabbing — the adhesive needs a solid background to grip.
Step-by-Step Instructions
Step 1: Prepare the Walls
Brush down masonry walls to remove loose material. Apply PVA diluted 1:5 with water to seal dusty surfaces — this helps the adhesive bond. For stud walls, check that all studs are straight and in the same plane.
Step 2: Apply Dabs (Dot-and-Dab Method)
Mix drywall adhesive (e.g., British Gypsum Gyproc Dri-Wall) to a thick, creamy consistency. Apply dabs approximately 50-75mm in diameter at 300mm vertical centres in vertical rows at 400mm horizontal centres. Apply a continuous ribbon of adhesive around the board perimeter and around any openings (doors, windows). The dabs should be about 25mm thick.
Step 3: Position the Board
Lift the board using a plasterboard lifter (foot lever) to raise it 10-15mm off the floor. Press the board firmly against the dabs. Use a spirit level and straight edge to check the board is plumb and flat. Tap gently with a rubber mallet to adjust. Hold or prop the board until the adhesive grips (usually 10-15 minutes).
Step 4: Cut Boards to Fit
To cut plasterboard: score the ivory face deeply with a Stanley knife along a straight edge. Snap the board along the score line. Cut through the paper on the back with the knife. For cutouts (sockets, pipes), mark the position, drill a starter hole and cut with a drywall saw. Always measure from the board edge, not from the wall, as walls are rarely perfectly straight.
Step 5: Board the Whole Room
Work around the room, fitting boards with 3mm gaps between them. Stagger the board joints so they do not line up in a continuous vertical or horizontal line. Board walls before the ceiling. When boarding a ceiling, screw into every joist at 150mm centres.
Step 6: Tape the Joints
Apply a thin bed of jointing compound over each joint using a 150mm taping knife. Press paper jointing tape into the compound while it is still wet. Run the knife over the tape to squeeze out excess compound and remove air bubbles. Allow to dry (usually overnight).
Step 7: Apply Finishing Coats
Apply a second coat of jointing compound using a 250mm knife, feathering the edges wider than the tape. Allow to dry. Sand lightly. Apply a third coat if needed, feathering even wider. The goal is a seamless transition from the joint to the board face. Fill all screw heads with compound.
Step 8: Finish Internal and External Corners
For internal corners, fold paper tape along its crease and bed it into compound in the corner. For external corners, fix metal or paper-faced corner bead with adhesive or screws, then skim with compound. Sand smooth once dry.
Common Mistakes to Avoid
- Boards too tight together: Leave a 3mm gap between boards for the jointing compound. Boards butted tightly together crack as they expand.
- Dabs too small or too far apart: Insufficient adhesive means boards pop off the wall. Follow the spacing guidelines exactly.
- Driving screws too deep: The screw should dimple the paper slightly but not break through it. Broken paper means the screw has no holding power. Use a drywall screw gun with a depth stop.
- Not staggering joints: Continuous joints across multiple boards create a weak line that cracks. Always stagger by at least 600mm.
- Skipping the PVA seal: Dusty masonry prevents adhesive bonding. Always seal first.
Cost Estimate (2026 UK Prices)
| Item | Typical Cost |
|---|---|
| Plasterboard 12.5mm 2400 x 1200mm (each) | £8-£13 |
| Drywall adhesive 25kg bag (each) | £8-£12 |
| Jointing compound 12kg bucket | £12-£18 |
| Jointing tape 90m roll | £3-£6 |
| Drywall screws box 500 | £8-£12 |
| Total for a 4m x 3m room, 4 walls (DIY) | £200-£400 |
Use our Plasterboard Calculator, Dot and Dab Calculator and Dry Lining Calculator for exact material lists.
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Frequently Asked Questions
For standard domestic walls, use 12.5mm plasterboard. For ceilings, use 12.5mm on joists at 400mm centres, or 15mm on joists at 600mm centres. For fire-rated walls, use 15mm fireline board. For wet areas, use 12.5mm moisture-resistant board.
Dot-and-dab (sticking with adhesive) is quicker and does not reduce room size as much. It works well on reasonably flat masonry walls. Battens are better for very uneven walls, damp walls (as they create an air gap), or where you need to run services behind the boards.
The ivory/white side faces outward (into the room). This is the side designed to be plastered or decorated. The grey/brown side goes against the wall or studs. For tapered-edge boards, the tapered edges should be at the vertical joints.
Fix at 150mm centres around the board edges and 200mm centres in the field (intermediate supports). A standard 2400 x 1200mm board on studs at 400mm centres needs approximately 32-36 screws. Use 32mm screws for 12.5mm board and 38mm screws for 15mm board.
Yes, but it is heavy work. A standard 2400 x 1200mm x 12.5mm board weighs about 22kg. You need a helper or a plasterboard lifter (available for hire at about £25/day). Start from one corner and work across. Screw into every joist.
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Last updated: April 2026
Verified against UK standards · estimates only, confirm with your supplier.