How to Fix Holes in Plasterboard

What type of holes does this cover?

Any hole in plasterboard where the board has been cut or broken through: socket and switch cutouts, spotlight holes, damage from door handles, holes left by removed fixings... Anything where you are looking at a void behind the board and need to create a surface to fill against.

For very large holes, where a significant section of board is damaged, cutting out the damaged area and fitting a new piece of plasterboard is the best approach. For anything up to around the size of a socket cutout, a backed repair is quicker and gives you a solid result.

Step 1: Prep - Create a Backing

First, clean up the hole. Trim any frayed or torn edges with a utility knife so you have a clean opening to work with. If the paper face of the board is peeling around the hole, cut it back to where it is still firmly bonded.

You will then need something behind the hole for the filler to sit on. There are a few ways to do this depending on the size and location of the hole.

For smaller holes, apply Self-adhesive Scrim over the opening. Centre the scrim over the hole and press it firmly onto the surrounding board. The scrim bridges the gap and gives the filler a mesh to bond into. This works well on holes up to around 50mm where the scrim can span the opening with enough overlap to grip the board on all sides.

For larger holes, cut a piece of timber or plywood slightly longer than the hole is wide. Feed it through the opening, position it behind the board so it spans the hole, and secure it with screws driven through the face of the plasterboard on either side. This gives you a solid timber backing to fill against. Make sure the timber sits flush with the back of the board or slightly recessed - if it sits proud it will push the filler forward.

For bigger repairs, cut a piece of new plasterboard to fit the hole. Screw a timber batten behind the existing board on each side of the opening, then screw the new piece of plasterboard to the battens. Tape the joints with scrim before filling. This gives you a flush, solid surface that is as good as the original board.

Step 2: Fill - Fill the Hole

Once your backing is in place, apply your chosen filler into the hole. For powder fillers, add water to the tub first then the powder and mix to a smooth consistency.

Using a filling knife, apply the filler firmly into the repair, working from the centre outward to feather out the edges. Press hard enough to bond the filler to the backing and push out any air. Build it up flush with the surrounding board.

The backing may sit slightly proud of the surrounding surface, but you can minimise this by feathering the filler out well beyond the edges of the repair to blend it into the surrounding board. The wider you feather out, the less visible the transition.

Step 3: Finish - Skim and Blend

Once the filler has set, sand back with medium-grit sandpaper (120 grit). Pay attention to the edges of the repair where the filler meets the existing board - this is where any unevenness will show through paint.

At this point, the hole is filled and repaired. For a finish that makes the repair disappear completely, apply your chosen Toupret finish product over the entire repair and feather it out well beyond the edges onto the surrounding board.

For a completely invisible result, skim the whole surrounding area rather than just the repair itself. Without a finish coat, the texture difference between filler and plasterboard face paper will be visible under paint - so do not skip this step if the finish matters.

Let the finish coat dry, then lightly sand. The repair is ready for decoration.