Project Overview

Learn how to plasterboard over the space left when a doorway is removed from a room. We show you how to build and install a frame for the space. You’ll see how to cut and install new plasterboard. You’ll also find out how to use base and top coats of plaster to create a smooth wall.
Continue to Step-by-step instructions.
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A simple tip for troweling a join

When troweling a join make sure the trowel edge is always in contact with the wall and the opposite edge is at least 10mm off the wall. That way you avoid scraping any of the plaster you’ve already done.

Step by Step Instructions

1 Install a timber frame for the doorway
2 Cut and install the new plasterboard
3 Fill the joins and apply plaster base coat
4 Apply your top coat and sand
  • Step 1. Install a timber frame for the doorway

    Measure the existing doorway space. Then cut your timber to size for the frame. Lay the timber piece out on the floor and nail the frame together. Stand the frame up, position it inside the doorway and nail it in place. In this case, because this doorway is over 800mm, we placed an extra stud in the middle to stop the plasterboard warping. Put some packer timber around the edges of the new frame so the new plasterboard will sit flush with the old plaster.

  • Step 2. Cut and install the new plasterboard

    Measure around the edges of the existing plasterboard and transfer these to a new sheet of plasterboard. Use a utility knife to cut the plasterboard to the right size. Now apply walnut sized amounts of plaster glue to the centre stud, spacing them about 300mm apart. Put the new plasterboard in place and nail it to the frame.

  • Step 3. Fill the joins and apply plaster base coat

    Mix some plaster base coat to fill the joins around the edge of the old door. Scrape back the wall, fill the joins with base coat and let it dry. Scrape the wall back again, then apply the tape along the joins. The tape helps to strengthen the joins and stops them from cracking. Now apply a layer of basecoat over the tape. Once dry, scrape it back again and add a second layer of base coat.
  • Step 4. Apply your top coat and sand

    Use a flat trowel to apply the plaster topcoat. Trowel on either side of the join to make it wider and to flatten out any imperfections on the wall. When applying top coat, it’s always handy to put it on thick and then scrape it back. This will give you a nice flat finish and make it easier to sand off. 

More D.I.Y Advice

Please make sure you use all equipment appropriately and safely when following the advice in these D.I.Y. videos. You need to be familiar with how to use equipment safely and follow the instructions which came with the equipment. If you are unsure, you may feel it is safest to consult an expert, such as the manufacturer or an expert Bunnings team member.

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