How to plaster a wall
By Tom Drake | 1st August 2023 | 5 min read
Plastering is a job that even the most confident of DIYers will steer clear of. However, with some preparation, patience and know how, you can plaster your own walls and achieve a smooth, professional finish.
1. Prepare the wall
The first step to plastering your wall is preparation. First, you’ll need to remove any loose plaster, dust and any other grime or imperfections that will prevent the plaster from adhering to the wall correctly. If you’re plastering over new plasterboard, use jointing tape to seal the gaps between the plasterboard sheets.
2. Prime the walls
Next up, you’ll need to prime the walls to make it easier for the plaster to adhere to them. To prime the walls, apply a PVA adhesive across the whole of the area that you’ll be plastering using a roller.
3. Mix the plaster
With your walls clean and prepared, it’s time to mix up your plaster. Fill a clean bucket with water then add the plaster slowly. For exact quantities of water and plaster, always refer to the instructions on your plaster.
You can mix your plaster by hand but we recommend using a power mixer at a low speed. Keep mixing until you’re left with a lump free mixture with a smooth, mud like consistency. As you mix, use a trowel to move any excess plaster from the edge of the bucket into the mix.
4. Apply the first coat
With the plaster mixed you’re now ready to apply the first coat. When plastering a wall, hold your plasterers hawk with one hand and your plastering trowel with the other. It can take some time to get used to these two, so start by working with small amounts of plaster on the hawk at a time.
Always start in the bottom left hand corner of the wall. Place a small amount of plaster onto the plasterers hawk. Then, take a small amount of plaster from the hawk and with your trowel angled slightly away from the wall, spread the plaster upwards using firm, even pressure. Towards the end of each stroke, flatten your trowel to help smooth the plaster down. Apply the plaster in a sweeping motion, with shorter sweeps to begin with, followed by longer sweeps which will help smooth the plaster. When you start your next stroke, slightly overlap the last to prevent leaving gaps.
Keep working across the wall until you’ve spread the plaster evenly across the whole surface. Lay the plaster as quickly as you can, if you leave behind trowel marks you can smooth these out later.
5. Smooth bumps & gaps
Leave the plaster to dry for 20 minutes, then go over it again with your trowel to smooth out any bumps or gaps that have been left behind. Here, you can use your spray bottle to wet the plaster slightly which will help the trowel move more smoothly. You can also use a wet paintbrush to help smooth out corners and edges.
6. Apply the second coat
Once you’ve smoothed the first coat of plaster, you can start on your second coat. For this coat you’ll use a thinner plaster mix, refer to the instructions on your plaster for exact quantities.
Apply the second coat in the same way you applied the first. Once the second layer has set, you can then use your spray bottle and trowel to smooth over any remaining bumps and use a paintbrush to smooth the edges.
7. Sand rough edges
If you’ve finished plastering and there are still a few bumps remaining, wait until the plaster has completely dried, usually around 24 hours, then use some fine grit sandpaper to smooth away any rough edges.
Dry lining a wall
Dry lining is an alternative to plastering a wall. Dry lining involves attaching plasterboard to a wall, then finishing it with jointing tape and jointing compound. It can be easier to achieve a good finish this way if you’re a beginner when compared to plastering. Take a look at our guide to dry-lining a wall for more information.
