Plastering your walls can be a cost-effective way to give your home a fresh look. It’s a skilled job that professionals spend years perfecting, but with time, effort, and patience, you can learn the basics and save yourself hundreds, if not thousands, of dollars. This guide will help beginners navigate plastering, explaining the tools, techniques, and common issues you’ll encounter.
Let’s get straight to the point.
Plastering is a cost-effective DIY skill that can refresh your home with practice and patience. Beginners should start small and gradually build confidence, knowing their first attempt will be challenging.
The process involves proper preparation, applying PVA, mixing plaster with water, and working in thin coats. Keeping tools clean and mixing small batches of plaster are key to success. After drying, you can paint or wallpaper the surface using a primer or mist coat.
Patching holes and repairing walls is also possible with basic knowledge. With time, effort, and these tips, DIY plastering can save you significant money.
What To Expect When Starting Plastering?
Plastering is an art; like any other skill, it takes practice. Don’t expect your first attempt to look as smooth as a professional’s work. Start with a small area and slowly build your confidence. One advantage is that plastering allows you to correct mistakes as you go—if the first layer doesn’t look right, you can always adjust in the next steps.
Plastering requires research and practice, but it’s one of those home improvement tasks that anyone willing to learn can do. With time and patience, you’ll learn to manage it independently.
Step-By-Step Guide To Plastering
1. Preparation
Start by laying dust sheets on your floors to protect them from debris. Make sure the area you’re plastering is clean. Repair any holes or cracks before applying plaster. Use screen tape to cover joints on newly installed plasterboard.
2. Apply PVA To Walls
Mix PVA (polyvinyl acetate) with water in a 1:4 ratio and apply it to the wall. This ensures even drying of the plaster. Once the PVA is tacky, you can begin applying plaster.
3. Mixing Plaster
Always mix plaster into water, not the other way around. Stir until the mixture resembles thick custard. Wear a mask to avoid inhaling plaster dust. Ensure there are no lumps in the mixture.
4. Applying The First Coat
Transfer the plaster from your hawk board to the wall using a trowel. Start in the lower left corner and work upwards, spreading the plaster evenly. Apply thin layers and press the float firmly against the wall. Continue this process until the entire area is covered.
5. Skim And Smooth
Wait 20 minutes after applying the first coat, then use the trowel to smooth the surface. Wet the edges with a brush to avoid rough edges.
6. Optional: Scraping Between Coats
Some people prefer to scrape the surface using a devilling float (a wooden float with nails) or a fork. This step isn’t necessary but can help the second coat adhere better.
7. Applying The Second Coat
The second coat should be thinner than the first—aim for a 2mm thickness. Dilute the plaster with water and apply it similarly to the first coat.
8. Finishing Touches
After the second coat dries slightly, spray the surface with water and smooth it with a trowel. For tricky areas, use a wet brush to ensure a smooth finish. Once dry, any bumps can be sanded off.
How To Mix Plaster Correctly?
Getting the plaster mixture right is one of the most important steps in a plastering job. Properly mixed plaster makes application easier and ensures a smooth, professional finish. Below is a detailed guide on how to mix plaster correctly.
Step 1: Gather Your Materials
Before mixing plaster, make sure you have the right tools and materials. You will need:
- A large bucket
- Plaster (multi-finish plaster is commonly used)
- A paddle attachment for a drill or an electric mixer
- Cold water
- A trowel for mixing by hand if needed
Ensure your bucket is clean to prevent dried plaster from contaminating the new mix.
Step 2: Add Water First
Always start by pouring cold water into the bucket before adding plaster. This helps prevent lumps from forming in the mix. Starting with water also ensures a smoother and more consistent mix.
Step 3: Slowly Add Plaster To Water
Gradually add plaster to the water—never add water to the plaster. This allows the plaster to absorb water properly and reduces the chance of lumps. As you add the plaster, use a paddle mixer attached to a drill to stir the mixture slowly. The key here is to keep a steady mixing speed without overworking the plaster.
Step 4: Aim For A Creamy Consistency
Continue adding plaster until you achieve a thick, creamy consistency. The mixture should be smooth, free of lumps, and thick enough to create peaks that stand independently when you lift the paddle out of the bucket. If the plaster is too runny, it won’t stick well to the wall; if it’s too thick, it will be difficult to apply and smooth out.
Step 5: Work In Small Batches
One of the biggest mistakes beginners make is mixing too much plaster. Plaster sets quickly—usually within 30-45 minutes—so mixing only what you can apply within that timeframe is important. Small batches minimise waste and give you enough time to apply the plaster smoothly before it starts hardening.
Step 6: Rest The Mixture (Optional)
If the plaster feels too loose after mixing, let it rest for a few minutes. This allows the plaster to thicken slightly and become more manageable. However, please don’t wait too long; it will start to set.
Cleaning Tools After Each Batch
It’s critical to clean your tools immediately after each mix. Any dried plaster left on the paddle, trowel, or bucket can ruin your next batch by causing lumps or uneven texture.
Step 1: Rinse The Paddle And Bucket
After mixing:
- Place the paddle in a bucket of clean water and run the drill quickly to remove any remaining plaster.
- Swirl the paddle in the water until all traces of plaster are gone.
- To avoid contamination, change the water after each batch of plaster.
Step 2: Use A Paintbrush For Thorough Cleaning
A damp paintbrush is useful for cleaning any remaining plaster off your tools, especially in tight spots like the corners of the bucket or along the edges of your trowel. This prevents dried plaster from falling into your next mix.
Step 3: Keep Tools Wet During Breaks
If you take a break, ensure your tools are wet or cleaned immediately. Plaster dries quickly and, once hardened, can only be removed by scraping or chipping, which could damage your tools and create issues for your next batch.
By following these steps, you can ensure that your plaster is mixed correctly and applied smoothly. Proper mixing and tool maintenance are key to achieving a quality finish when plastering.
Essential Tools For Plastering
Here’s a list of must-have tools for plastering:
- Trowel: A good trowel is essential for applying and smoothing plaster. Invest in a professional-grade trowel for better results.
- Hawk board: This holds your plaster while you work.
- Bucket trowel: For transferring plaster from the mixing bucket to the hawk.
- Paintbrush: Use this to clean your tools and wet the plaster edges.
- Spray bottle: Keeps the plaster surface moist for easier smoothing.
Multiple trowel sizes are also useful, as working in tight spaces with large trowels can be tricky.
Painting And Wallpapering Over Plaster
Once your plaster has dried, you can begin painting or wallpapering. Apply a primer or undercoat first. This helps seal the surface and improves the adhesion of the final coat. When wallpapering, use wallpaper adhesive to ensure proper bonding.
Mist Coat For Painting
A mist coat, a watered-down version of your top coat paint, helps seal new plaster. After the mist coat, apply two coats of your chosen paint for an even finish.
Repairing Damaged Walls
Not every plastering job requires covering an entire wall. Often, you can patch small holes or cracks. For smaller holes, a filler is enough. Larger holes require new plaster.
Steps For Repairing Holes:
- Clean the hole and surrounding area to remove loose debris.
- Apply plaster to fill the hole. Multiple coats may be needed for deeper holes. Scratch the first coat lightly with a fork or devilling float before applying the next.
Applying its two layers of plaster is often necessary for larger holes to achieve a smooth surface.
Conclusion
Plastering requires patience and practice, but it’s a valuable skill. Start small, learn the basics, and you’ll become more confident in your abilities with time. Use PVA to ensure even drying, apply thin coats of plaster, and always keep your tools clean. Once the plaster is dry, you can paint or wallpaper for a smooth, polished finish. With these tips, you can take on plastering projects and save considerable money.
FAQs About Plaster Paint
What Happens If You Paint Over Plaster?
Top tip: If you don’t let the plaster dry and apply emulsion paint to wet plaster, it’s likely to crack and peel off. Painting new plaster that’s completely dry can also leave you with uneven brush strokes. So, the next action is to create your mist coat paint.
How Do You Know If Plaster Is Ok To Paint?
Ideally, the plaster needs to be fully dry before painting. Fresh plaster will take around 4-6 weeks to fully dry. Fresh plaster is porous and will, therefore, absorb moisture. If you attempt to paint over plaster that is still damp, the paint is likely to peel off.
What Paint Do You Use On Plaster?
Use a white emulsion (it doesn’t need to be high quality), as this provides a good base colour for any top coat. A common ratio is seven parts paint and three parts water, but you can go 50 50 if you use thick paint. It’s better to be too thin than too thick.
How Many Coats Of Paint Does Plaster Need?
When painting over new plaster, you’ll technically want three coats of paint – our two recommended coats plus a mist coat. A ‘Contract matt’ is specially designed for use on new plaster.
Can I Paint Directly Onto Plaster?
In most cases, you can paint straight onto/over plasterboard; you need to cover the joints and any holes created by your fixings first. Painting directly onto the surface of the new wall is convenient and saves time and money. You can also plaster over the painted plasterboard at a later stage.
