A Guide to Wall Plastering
A Guide to Wall Plastering
This is Part 1 of a multipart series. Links to the rest of the series can be found at the bottom of this page. In this blog post we’ll cover different types of plasters, and the tools and materials required for plastering a wall.
Plastering is one of the final steps in finishing an interior or exterior wall. While applying plaster is a technical process, you don’t have to pay a professional to get it done. Anyone can do it provided they follow a few key guidelines and have the right kit and materials.
Tools and Materials Needed for Plastering a Wall
It’s always a good idea to be fully prepared for a DIY job so you don’t have to down tools and leave the job halfway through to stock up. This is even more important during a plastering job, where plaster can dry out if left unattended. You don’t necessarily need all of these exact items – but you will need items that will do the same job:
- Plaster – In the quality and quantity needed for the job
- Plasterer’s trowel – used for scooping and spreading plaster
- Plasterers Float – for smoothing over the plaster and making sure it is as flat as possible
- Corner Trowel – for finishing off those corners easily
- Hawk – for holding plaster during the job keeping it close at hand
- Bucket – for mixing the plaster in
- Mixing stick and/or paddle – to mix the plaster to a good consistency
- Clean water – to mix into the plaster
- Sandpaper – to smooth down any rough patches once the plaster is dry
- Stepladder, platform, or stilts – to reach every piece of the wall and/or ceiling
- Face mask and goggles – to stop you breathing in plaster powder, and protect your eyes during the work
Wall Plastering: Types of Wall
Before you get started, it’s important to figure out what kind of wall you're working with. Different plasters will work best on different walls, so before you buy your plaster, you’ll need to make sure it will stick to your wall. There are three types of wall, or ‘backgrounds’, in the plastering world - high suction, medium suction, and low suction backgrounds.
High suction backgrounds mean that the wall is porous – as in it will quickly suck moisture from the plaster while you’re applying it. The benefit of applying plaster to a high suction wall is that it will stick very well, but it might dry out too fast or crack as it dries. To solve this issue, apply water to the wall prior to plastering until it runs down the wall – that means the wall has absorbed all the water it can won’t leach it out of the plaster.
Low suction backgrounds mean that the wall is only slightly porous - so it won’t take the moisture out of the plaster. The benefit of plastering a low suction background is that you don’t have to worry about the plaster drying out too quickly while you’re applying it, but there are some drawbacks. One is that the plaster will only dry by setting naturally, so you might have to wait to continue decorating. Second is that a low suction wall needs to be prepared before applying the plaster. Make sure to use a bonding agent so your plaster sticks (more about that later).
Medium suction backgrounds are the middle-ground. An example of a medium suction surface is normal household brickwork. These types of surface are the Goldilocks of plastering – just right. You’ll need to dampen the wall a little to improve adhesion of the plaster, but if you take the time to smooth the plaster over before it begins to dry, it should stick pretty well.
Different Types of Plaster
You can purchase a range of plasters for different build situations and finishes. As mentioned above, some plasters are more or less suitable for various wall types, so be sure your chosen plaster will be suitable for the area you’re plastering.
This is an undercoat plaster also known as fixing plaster. Before you apply your top coat or ‘finish’ plaster to a wall, you might need to use a bonding plaster first to help the top coat of plaster stick to the wall effectively. Bonding plaster is ideal for walls and ceilings that have a smooth finish. Simply dampen the wall’s surface before applying, and you’re all set to begin. The consistency of bonding plaster allows you to spread it smoothly and get a good finish.
Hardwall plaster is another type of undercoat plaster and one of the fastest drying plasters, and is mostly used on masonry surfaces like aircrete and medium density blocks, and bricks. Before application, dampen the wall surface and apply to the wall by pressing the plaster on with high pressure to get the best result. You can also spray it on, which is a fasterwork but will require more dust sheets to protect other areas of the room.
Multi-Finish Plaster is perfect when you have a variety of surfaces to cover, and it works best for low to medium suction backgrounds. The setting time for the Multi-Finish Plaster is a speedy 90 minutes, which makes it a good choice for projects on a time limit. It can also serve as a good base if you want to add some decorative finishes. For best results, make sure you apply it with firm pressure to get a high-quality and smooth finish.
If you want a smooth surface to paint on, this easy-fill is the best solution for bulk filling as well as smoothing out the walls ready for decoration. Easi-Fill joint filler creates a consistently smooth finish and is easy to mix and apply. It’s a lightweight product ideal for quick-fix repair jobs, chasing in (which means cutting a channel to accommodate pipes or cables) and patching.
Skimcoat is a gypsum-based thin plaster which is easy to apply and can be used on a wide range of surfaces. It’s a multipurpose plaster for gypsum and cement-based undercoat plasters, masonry and plasterboard surfaces. Its long workability time enables an easy application with a low waste rate.
Joint Filler is perfect for filling in channels where pipework has been laid (bedding in), bulk filling and neatening up joints between plasterboards. It is a low shrinkage
product designed to be applied by hand so that you can get a high quality, smooth surface, ready for decorating.
Finish Coat Plaster
The finish coat plaster provides superb results and a high-quality surface for internal walls and ceilings - it is the best choice for plastering and offers a durable base for the application of decorative finishes. It has a setting time of only 2-3 hours, and is scratch resistant to avoid any further patching up following its application.
DriWall Plaster (Adhesive)
Gypsum-based adhesive is a general purpose adhesive for use on high, medium or low suction backgrounds. It can be applied directly to masonry backgrounds with the purpose of applying plasterboard. It’s one of the swiftest ways to line your walls.
The products below come ready-to-use, so there’s no need to measure and add water before you get to work.
Joint Filler is a ready-mixed lightweight jointing product for use after you’ve finished your main plasterwork. Using this joint filler helps hide seams and connections along walls or ceilings prior to painting. This particular product is compatible with the majority of airless sprayers, but you can also apply it with a trowel as with normal plaster. Another benefit is that it’s much easier to sand down than other similar products.
Thistle Bond-It is specifically designed for hand or machine applications and formulated to be applied on smooth or low suction backgrounds. It is a bonding plaster, so it is not meant for use as a final coat but instead a bonding agent to allow the top coat of plaster to stick to the surface effectively. With that in mind, it has a pale green colour which enables you to identify where you’ve plastered so far, so you don’t miss any parts of the wall.
Plasting Guide: The Complete Series
You’re almost ready to begin your plastering project, however we recommend continuing to read the rest of our handy guides on plastering before you get started. These include useful information and ‘how to’ videos to help you get the best finish.
This step-by-step guide to plastering will ease you through the job. Hopefully, the finished result will look as if a professional completed it.</li>
Part 3: Why Does Plaster Crack?
In this part, you will learn about the reasons for the cracks in plaster and how to avoid them
Part 4: A Step-By-Step Guide to Repair Cracks in Plaster Walls
This step-by-step guide will help you understand how to fix the cracks in the plaster wall.
Know what kind of plaster you need? Or want to look for more options? Why not head over and browse the full range of plaster options using our easy-to-navigate menu options, or talk to our team on live chat to find the product that’s right for your next project.