To some people, a brick wall finish looks rustic and unique. Others, however, don’t find it so appealing. We all have different tastes, and if you have recently moved into a home with a brick wall finish, you may consider covering it up with plaster.
Structo-Lite is one of the most popular plasters. It is a mill-mixed perlite-aggregate gypsum plaster that is lightweight and can improve insulation. It is easy to apply and quite durable.
When you look at the manufacturer’s description, they say that Structo-Lite can be used on concrete, clay tile, metal lath, gypsum, or cylinder blocks.
Unfortunately, brick is not on that list. Therefore, if you plan to use Structo-Lite plaster over brick, you may have doubts about whether it will hold up. That’s exactly what we are going to discuss in today’s post.
By the end of this article, you should know whether it’s okay to use Structo-Lite over brick and some of the techniques you can use to prevent failure.
Can You Use Structo-Lite Over Brick?
Absolutely. Structo-Lite gypsum plaster can be used over brick, and it can hold up well if you apply it correctly.
If you don’t like the brick wall finish, a layer of Structo-Lite can help you decorate your walls and achieve a more aesthetically pleasing finish.
Even though USG doesn’t mention brick as a Structo-Lite substrate, many people have successfully plastered brick walls with Structo-Lite. And so can you!
Structo-Lite will stick to brick, but there are a couple of techniques that ensure it stays on and doesn’t crack or fail. I will share these techniques with you so that you can effectively cover a brick wall with Structo-Lite plaster.
A Quick Guide on How to Use Structo-Lite Over Brick Walls
Step 1 – Gather All Essential Materials
Here are a couple of things that are needed for you to apply Structo-Lite over brick;
• A bag of Structo-Lite (The size will depend on the surface area of the brick that’s about to be covered)
• Some denatured alcohol
• Wire brush
• Soap and water
• A trowel
Step 2 – Create Micro Abrasions on the Brick
One of the reasons most plaster jobs on brick fail is that many people go directly into applying plaster on the brick surface. Preparation is a vital part of the process and guarantees the project’s success.
Using your wire brush, make micro-abrasions on the brick’s surface. These will come in handy in facilitating adhesion. This step may need a lot of elbow grease, but it’s 100% worth it.
Step 3 – Clean the Brick Wall
Even though a brick finish looks great, this design is a bit old-school. That means most finishes with a brick wall are old and may have accumulated a lot of dirt and contaminants. Take your time to clean the brick before laying the Structo-Lite.
You can start by scrubbing the brick with some denatured alcohol. That will take care of the stubborn dirt and contaminants. Then you can move on to the soap and water mixture.
Rub the brick walls thoroughly with a wet sponge. The sponge will help remove any dirt particles and traces of denatured alcohol. Give the surface time to dry before moving to the next step.
Step 4 – Apply Plaster-Weld
If you have engaged in many plastering projects, then you must be familiar with Plaster-Weld. This is a product made by Larsen, which is very effective at bonding new plaster to any surface, brick included.
Plaster-Weld is the secret ingredient in this project. It ensures that your Structo-Lite plaster adheres firmly to the brick.
Plaster-Weld is available online in stores such as Amazon. You can also look for it at a store near you. Apply Plaster-Weld using a brush. A single coat is usually enough. But you can go with two if you prefer a stronger bond.
Step 5 – Bring out the Structo-Lite
If you have followed the above four steps keenly, your brick wall should be adequately prepared for some Structo-Lite plaster. Prepare the Structo-Lite.
Remember, the manufacturer recommends a stiff viscosity. Therefore, don’t pour a lot of water than advised. Mix it thoroughly until you get a smooth and lump-free consistency.
Using a trowel, apply the Structo-Lite over the plaster-weld brick walls. It’s pretty lightweight. Therefore application should be a breeze.
Start with a thin first layer, then smooth it with another coat. How smooth the finish is will depend on your plastering experience.
When you are done, give it time to dry, and you will be all good. It’s also important that you work fast. Otherwise, the Structo-Lite might set when it’s still in the bucket. As it sets, it turns much darker.
And that’s how you should correctly apply Structo-Lite over brick.
Does Brick Suck Out Moisture from Structo-Lite?
Since bricks have a more diffusion-open surface, they can easily suck moisture out of the Structo-Lite. This is the leading cause of Structo-Lite failure over bricks.
There are two ways you can prevent bricks from sucking out moisture from Structo-Lite;
• Dampen the brick wall with water before plastering
The science behind this method is pretty straightforward. Because plaster contains moisture, to prevent brick walls from sucking in this moisture.
They should be dampened with water. This will ensure the plaster retains its moisture content and dries without interference. This strategy is popular in DIY plastering jobs. But experts prefer to use the method I will be sharing next.
• Use a liquid lath to bond plaster to the brick wall
When your brick walls are filled with water, they won’t need to absorb the moisture in Structo-Lite. But the above method has a lot of weaknesses. For instance, what if you don’t use enough water?
If you prefer a method with peace of mind, you should use a liquid lath. A product such as Plaster-Weld will promote the adhesion of plaster to brick. It ensures the plaster cures at its own pace and doesn’t fall off when the bricks suck out moisture.
Using a liquid lath will act as a bonding agent between the Structo-Lite plaster and the brick walls. Unlike dampening the bricks with water, this is a more reliable method.
Should You Apply Structo-Lite Over Cracked Brick?
In my experience, cracks on materials such as brick will always find a way to the surface. Before plastering over a brick wall, you need to examine it thoroughly. Since brick is typical in old homes, there is a high probability of finding cracks.
Should you find cracks, don’t apply Structo-Lite over them. Remove any loose bricks and apply a filler first. Then proceed to rough up the area, and this time around, use a fiberglass lath instead of the liquid lath.
Fiberglass will reinforce the strength of the Structo-Lite plaster, and any cracks on the brick won’t be transferred to the plaster.
What May Cause Structo-Lite Failure Over Brick?
If you look up several online forums, you will see horror stories of how Structo-Lite fails when applied over brick. This, however, shouldn’t scare you because on the other end of the spectrum.
Many people have successfully covered brick walls with Structo-Lite, which has lasted for years without cracking or falling off.
To ensure your Structo-Lite installation over the brick is a success, here is a list of some of the common culprits that may lead to failure;
• Moisture – Bricks love soaking in moisture. When you apply Structo-Lite directly, the bricks will soak up all the moisture and affect the curing process of Structo-Lite, causing it to crack or flake.
• Damaged Bricks – It is impossible to create a smooth finish on a damaged surface. If the bricks are worn out, cracked, or in terrible condition, they must be repaired before you can put anything on them.
• Dirt and Contaminants – Preparation is vital when installing Structo-Lite over brick. The presence of dirt and contaminants can affect adhesion. It’s, therefore, a good idea to thoroughly clean the walls with alcohol and soapy water.
• Lack of a Bonding Agent – As tempting as it may be, never skip the step of using a binding agent. Without one, the adhesion will be weak, which may fail.