Stucco has long been used in construction as a coating for a building’s exterior, walls, ceiling, and sculptural materials in architecture. The material is made of aggregates, a binder, and water and applied wet before it hardens into a very dense solid. Due to its durability, attractiveness, and weather-resistance, many people stucco their masonry, brick, or concrete walls — you can do it on your own, too.
To stucco a concrete wall, clean the wall first if the wall doesn’t absorb any water or if the wall surface is contaminated, and moisturize it. Then, you want to mix, apply, and mark the scratch layer before applying the brown coat. The final layer can be a pigment or color.
In this article, you will learn the following:
- What stucco is and why you should stucco your concrete wall
- Different types of stucco
- Steps on how to stucco a concrete wall
What Is Stucco?
Portland Cement Plaster (stucco) is a construction material widely used on indoor and outdoor building surfaces. Despite its low cost, stucco is durable, doesn’t rot quickly, and can resist fungus well. Plus, the material does not require much maintenance, making it a popular exterior material choice for DIY projects.
Traditional stucco is made from lime, sand, and water. The modern stucco we have today is made of Portland cement materials, sand, and water. All the materials mentioned are mixed to create a plaster that can be spread on walls, ceilings, or other structures, to make a smooth, hard surface once hardened and dried.
Usually, it would take a professional to help you stucco your wall, but you can also do it yourself with the right techniques. You can use stucco on concrete wall systems or a frame structure. Stucco is typically used to cover concrete, cinder block, adobe, or clay brick.
Advantages of Stucco
There are several benefits of using stucco. One of the advantages is you can save on construction costs and still achieve a strong and durable finish. The material is versatile as it is suitable for various climates.
Other benefits include:
- Available in various pigments
- Color retentive
Disadvantages of Stucco
While stucco is an excellent product for giving your building a makeover, it does have its weaknesses. For example, stucco is porous, which means it is not waterproof, so water can penetrate the material slowly, causing the stucco to crumble eventually. An extended period of water exposure can also damage the home frame in the future.
On the bright side, homeowners can tackle the water problem by finishing the home areas that mostly come in contact with moisture. That way, the stucco can survive the wet seasons. Homeowners can add finishing to the bottom footing or the top of their home using a different material instead, like brick or vinyl.
Another downside of stucco is that it’s challenging to repair. People who live in moist or snowy climates have to fix their stucco buildings frequently. Since stucco involves multiple layers, you have to get all those layers fixed, which can be very time-consuming and expensive.
Different Types of Stucco
You can find two main types of stucco: traditional and synthetic. Whether you use a traditional stucco or synthetic stucco, your home will look great. Both traditional and synthetic stucco have their strengths and weaknesses, which we will discuss shortly.
Unlike today’s stucco, mixed with cement, traditional stucco is made of lime, sand, and water. Having cement in the stucco is useful for adding more durability. Lime, however, only encourages mold growth, which is why it is not always favored.
Sometimes, traditional stucco has glass fibers and acrylics to achieve more durability. With pure hard cement stucco, a stable mesh base must be present to prevent stucco from cracking. Stucco can last about 50 years if applied carefully and given proper maintenance.
Synthetic stucco uses acrylic resin instead of cement and lime. Synthetic stucco is water and damage resistant, which gives it an advantage over its traditional counterpart. Working with synthetic stucco is also easy since it dries evenly and quickly.
You can apply synthetic stucco over foam board rather than mesh. Today, many construction projects use foam board because the material is super lightweight, easy to cut (using a utility knife), and waterproof. The acrylic resin also enables the stucco to move, making it more durable and reducing the risk of stucco cracking and breaking.
Is Stucco Easy To Work With?
Stucco is easy to work with, so you can stucco your concrete wall on your own if you like. You must stucco your wall carefully to ensure you’re getting the best, long-lasting results. We’ll show you how it’s done.
You’ll need to apply stucco twice on your concrete wall — make sure your wall is clean. Before you start your DIY project, you need to check the building codes for wall assembly and moisture barrier requirements in your area. When using water-resistant stucco walls, you need to use water-vapor permeable Grade D building paper over the wall’s sheiling — use two layers.
Other important things to have before applying your base coat stucco:
- Concrete board
- Exterior gypsum board
Secure Your Water-Resistant Building Paper
When applying the Grade D building paper, make sure you secure the material to the wall using a hammer.
When you attach the water-resistant building paper, you must ensure that vertical seams are overlapped by six inches (15.24 cm) or more, whereas horizontal seams are overlapped by four inches (10.16 cm). Your building paper must extend 40.64 cm or 16 inches around all corners.
Install Trim Accessories, a Weep Screed, Casing Beads, and Galvanized Netting
After you’ve secured your building paper, install trim accessories. You can cut trim accessories into different sizes using metal snips. Make sure you put on gloves when handling trim accessories as the edges are sharp.
It’s essential to install a weep screed, a particular piece of metal flashing installed to the bottom of the walls. A weep screed is usually necessary for this type of project. The weep screed helps in wicking moisture or water out of holes located at the bottom of the flashing.
You need to install casing beads as well to stop stucco when you reach the end of the wall. The casing beads will be your guide in maintaining the consistency of your stucco thickness. Your casing beads have to be 1 ½ inch (3.81 cm) thick as you are working with a concrete wall that has to be applied with stucco twice.
Install a galvanized expanded steel lath over the surface. Overlap the net against the body carefully, about 1 inch (2.54 cm) on the horizontal seams and 2 inches (5.08 cm) over the vertical seams. Stapled nails have to be placed vertically and horizontally every 6 inches (15.24 cm).
The nails have to be appropriately stapled into the stud at least 1 inch (2.54 cm). The lath should be 16 inches (40.64 cm) on all angles. If the base stucco is applied to a clean, unpainted concrete surface, a waterproof building or paper lath is not required.
Install Control Joints and Expansion Joints
Use control joints to form wall panels measuring at 144 ft² (13.378 m²). Stucco will shrink as it cures, so you want to use control joints to reduce shrinkage cracking. It would be best to use expansion joints inside the corners that change in substrate.
You want to allow the stucco wall panels to expand or contract when the temperature changes. Use a corner trench on the structure’s edges to protect the stucco. The corner trench will also give you clean finish lines.
Prepare Your Stucco
You can use the QUIKRETE Base Coat Stucco for your concrete wall DIY project. The QUIKRETE base coat stucco is a pre-blended stucco that is easy to work with, perfect if you are using hands to apply your stucco. With QUIKRETE, you can achieve a strong bond strength.
Mix your base coat stucco with water properly until you get the right consistency. You know the mixture’s consistency is correct when your stucco can easily sit 90° on the trowel. If your stucco is too wet, that means the consistency is not right.
Stucco that’s mixed too wet will sink easily, whereas stucco that’s too dry won’t mix properly and take much longer to reach the proper consistency. Don’t add too much water at a time. Instead, add water throughout the mixing process until you get a perfect consistency.
You can mix your base coat stucco in a wheelbarrow. This method is easy and great for small DIY projects. You only need a few tools, such as a wheelbarrow, a hoe, a water hose, and a base coat like QUIKRETE.
Another way to mix your base coat is by using a bucket and a drill. This method is also perfect for small DIY projects. It would be best if you had a shovel to measure your sand and cement, which is not always easy.
Other tools you need for preparing your stucco with the bucket and drill method:
- Mixing drill
- 2-3 5-gallon (18.9-liter) buckets, depending on the area size you want to cover
- Mixing paddle
- Water hose
You can prepare your mix using a mixer. Use this method if your DIY project is medium or large. By using a reliable mixer, you can work on bigger jobs quicker, and it would help to get some friends or family members to help out, too.
Apply Your Stucco
Apply the base coat stucco using square trowels and some pressure, ensuring the stucco gets into the lath. Then, apply the stucco from the bottom of the wall all the way up and spread the thickness in about ⅜ of an inch (9.53 mm) over the surface. Use a darby or a straightedge to make the stucco uniform, about ⅜ of an inch (9.53 mm) deep.
Create the Scratch Coat
Using a stucco raking tool, make horizontal scratches on the base coat, about 3.175 mm deep. Wait for the scratched stucco to cure up first, between 24-48 hours. Spray fine water mist on the stucco surface using a hose to keep it damp to reduce shrinkage cracking, especially in hot, dry weather.
Add the Brown Coat
Using trowels, apply another layer of base coat stucco to the scratch coat stucco — this layer is known as the brown coat. Use a straightedge or darby to smooth out the brown coat, and if there are any surface voids after smoothing out the brown coat, add additional base coats to cover the voids. The overall depth of your base coat will be 3 ¼ of an inch (8.255 cm) thick.
Uniform the Surface
Make sure the surface of the stucco is uniformed. Then, spray the surface with water mist to cure it for between 24 and 48 hours — you may want to moist cure it several times a day. Once dry, you can add color to your wall using a new batch of stucco.
Add Color to Your Wall
The QUIKRETE finish coat stucco can be used to create decorative colors for concrete walls. There are two colors available: white and gray. You can combine the finish coat stucco with over 20 standard QUIKRETE and mortar colors of your choice.
Several textures can be achieved, depending on your preference, and require some practice, such as:
- Cat face
- Lace and skip
- Worm/swirl or putz
- Santa Barbara
Textures such as heavy lace, light lace, dash, or sand/float are beautiful and easy to make, coupled with some practice. Apply about ⅛ inch (3.175 mm) of thick finish coat stucco, from the lower section of the wall all the way to the top. Use a whisk brush to apply your finish coat stucco to the wall.
If you want a heavier texture, you need to apply thin finish coat stucco evenly that also ensures you have the color spread out adequately. After applying the light application, apply another batch of stucco, this time heavier and uneven. Then, knock down the finish that’s about to harden using a trowel, creating a lace texture.
If you prefer a smooth texture, use a trowel or sponge float in a circular motion on the surface. It would be best to complete your project in a single application to prevent color inconsistency. You want to ensure the surface stays damp, so use fine water mist to keep it damp for several days.
Different Stucco Finishes
Earlier, we’ve mentioned the different stucco finishes you can use for your concrete wall, depending on your preference. All stucco finishes are beautiful, but you want to choose the type that suits your home best. Let’s discuss the finishes.
The cat face is ideal for homeowners who like large concrete areas to be smooth, with evenly placed rough patches. The rough patches are known as inclusions, and they may vary in size and shape. You can achieve the cat face finish by using acrylic or traditional or synthetic stucco.
Lace and Skip
Commonly used on homes and commercial buildings, the lace and skip finish is rough, with imperfections that are easily hidden thanks to its texture. You can create this finish using your hand or spraying it on the surface and then flattening it with a trowel. You need to apply two coats to create this look, a base coat and then the texture.
Commonly used for commercial buildings, the sand or float finish is versatile and can be used on traditional and synthetic stucco with just a single coat. Since it is quick and easy to do, it would be perfect for your first DIY stucco project. The sand or float comes in three different finishes: fine, medium, and coarse.
The dash can be sprayed onto homes in light, medium, or heavy volume, creating a unique look of its own. You can apply this texture by hand if you’re working with smaller areas or by a hopper gun if you’re working on larger areas. Ideal for homeowners concerned with cracking, the dash can be changed with 1-3 coats.
Worm/Swirl or Putz
Also known as the swirl or putz finish, the worm involves a trowel moving large aggregate pieces in stucco across the surface to create indents on the stucco surface. The finish is not as popular as it once was, perhaps because it’s not easy to fix once it’s cracked. However, some modern homes today still use it, thanks to its unique texture.
If you like your walls to be smooth, then the smooth texture will be perfect for you, but it is also one of the most challenging finishes to achieve. The smooth texture is very popular because it can be easily colored and matched with a building’s aesthetics. This texture also makes it very easy for people to use different colors to give their walls the “mottled” look.
Santa Barbara is perfect for people who want an adobe-style finish. It is only used in traditional stucco applications. Fine sand particles are used to achieve the adobe look. You will get a beautiful smooth finish with this texture, but it is prone to visible cracking.
Even though the English texture isn’t popularly used in modern buildings, those who like to give their walls a romantic aged look will find this texture perfect. You will still see buildings with this texture, mostly older buildings. If you want to use this texture, you must only use traditional stucco.
Stucco has long been used in construction as a coating for a building’s exterior, walls, ceiling, and sculptural materials in architecture. You only need a 2-coat system to stucco a concrete wall. QUIKRETE base coat stucco is perfect for the job.
You must prepare your stucco mixture correctly and follow all the steps required to stucco your concrete wall successfully. There are various types of stucco to choose from, depending on your preference. You can color your wall by combining the QUIKRETE finish coat stucco with QUIKRETE the color you like.