What Every Homeowner Needs to Know About Stucco

Stucco is one of the oldest options for cladding the outside of a home. This unique material has been in use for centuries, and it remains a good option for Arizona homeowners today. Around a quarter of homes feature stucco siding, which makes it the second-most popular modern option right after vinyl. This article will take a look at what homeowners need to know about stucco as an exterior finish.

What Is Stucco?

Stucco is a cementitious product that can be used in interior and exterior applications. Traditionally, this versatile building material was made out of lime, sand, and water. However, modern systems are now in use that provide longer-lasting results, reducing the need for frequent stucco repair.

Types of Stucco

Modern stucco usually contains a mixture of sand, water, and Portland cement with lime added to improve workability and permeability. There are also systems available that use additives like glass fibers or acrylics to improve the material’s structural properties. Some provide better insulation, while others suppress cracks and address other common issues.

Traditional vs. Synthetic

Although technically, traditional stucco contains only sand, lime, and water, most contractors now consider the addition of cement to be acceptable. Glass fibers and acrylics can also be added to traditional stucco for improved strength.

Synthetic stucco doesn’t use cement or lime. Instead, it features an acrylic resin that provides a greater level of moisture resistance. Synthetic stucco is typically used in insulated systems since it can be applied over foam boards and is less prone to cracking and breaks in most applications. However, it’s much less cost-effective than traditional stucco.

The Different Stucco Finishes

When homeowners choose to work with stucco, they can take advantage of a range of finish options. They include:

• Float/sand finish featuring coarse, fine, and medium patches.
• Dash finish, which can be sprayed on instead of applied with a trowel.
• Lace and skip finish, a rougher option with a varied texture that’s great at hiding imperfections.
• English finish for traditional stucco.
• Santa Barbara finish for traditional stucco, which uses fine sand particles to mimic the look of adobe.
• Cat face finishes with large areas of smoothed-out stucco and evenly placed rough patches called inclusions.
• Smooth texture finish, a challenging-to-apply option that works best with synthetic stucco.
• Worm finish, featuring large pieces of aggregate, was a popular application method but has since gone out of style.

Stucco Application Systems

Finally, there are three common systems for applying stucco. The first is a 1-coat hard coat system, also called a 2-coat system since it features not just a single coat of stucco but also a cement base.

The second is the typical 3-coat system used to apply traditional stucco in exterior applications. Using this system involves applying a water-resistant barrier of asphalt-infused paper followed by a layer of wire, a scratch, and a brown layer. Finally, the primer and finish coat are applied over all of it.

Last is the exterior insulation and finish system. This system is called EIFS for short and uses thinner layers and requires no hard coats. Some EIFS applications also feature an extra water management layer called a moisture barrier.

Common Applications

The most common application for stucco is as exterior siding for homes in the Southwest and Midwest. However, it can also be used for purposes like enhancing the appearance of brick, stone, or block fencing and in other hardscaping applications.

Not everyone realizes this, but stucco is often found inside homes, as well. Some people refer to it as plaster, and there are sometimes differences in application methods. However, the materials are the same. Plaster simply refers to a general term for materials applied in thin layers to walls, while stucco refers to a specific type of plaster.

How Stucco Is Applied

The stucco application process varies slightly depending on what system is being used and the base material to which it is being applied. However, the basics are the same no matter where stucco is being applied.

In most cases, this material can adhere directly to materials like bricks and stones, which makes using it to coat block walls incredibly efficient and effective. When applied as siding, contractors usually use felt paper and lath or a house wrap to improve the stucco’s ability to adhere to the home.

Traditional stuccos are applied in three coats using a hand trowel. The first two coats are typically rough and contain larger amounts of aggregate, while the third one is a finish coat that can accept different colors and textures but is typically finer.

Newer systems vary in terms of application methods. Crack suppression systems require four coats, for example, and insulating systems must be applied to polystyrene foam boards covered in fiberglass mesh. The general rule when working with newer, more advanced stucco systems is to find a contractor with specialized experience working with those products.

Taking Care of Stucco

Experts do not recommend applying or repairing stucco without dedicated training and experience. However, there are some things that homeowners can and should do to protect their walls. They include:

Cleaning Gutters

If a home’s gutters are clogged, that can spell disaster for exterior stucco walls. Water leaking from the gutters and down the sides of the building can cause substantial damage, including cracks and staining.

Removing Dirt

Stucco doesn’t usually need regular cleaning. However, if it begins to look dirty, homeowners may want to clean the wall. The best way to do that is to use a hose with mild pressure to rinse away the dirt.

Painting Stucco

Some homeowners opt to omit colors from the finish coat and apply paint instead. As with any application for exterior paint, the color will fade over time. In hot, sunny climates, fading can be even more of a problem, but thankfully, resolving it requires nothing more than periodic repainting to refresh the appearance.

Performing Inspections

Homeowners should take the time to inspect their stucco walls frequently so that they can schedule repairs as soon as issues come up. Cracks can allow water to seep behind the stucco finish, causing significant damage if left unaddressed. Some homeowners also opt to schedule annual inspections with a professional who can identify less obvious forms of damage.

Addressing Landscaping Concerns

Homeowners should avoid planting trees or shrubs right next to stucco walls, as they can rub against it and damage the finish. Soil levels that extend above the bottom level of the stucco can cause similar issues, as can planters affixed to the walls.

The problem is that stucco is porous, which means it will draw up moisture from the soil and other water sources. Avoiding this issue is a simple matter of paying attention to landscape maintenance. In addition to the above-described design considerations, homeowners should use drip irrigation rather than sprinklers near the perimeter of the home.

The Pros and Cons of Using Stucco

Stucco is one of the most popular types of exterior finish for good reasons. However, there is no building material that’s appropriate for every situation, and this is no exception. Learning about the pros and cons of stucco can help homeowners make informed decisions about whether it’s the right option for their exterior siding, block walls, or interiors.

Pro: It’s Durable

Stucco has serious staying power and can remain in good condition for decades with very little maintenance as long as it’s applied properly. Unlike vinyl siding, which typically lasts only a few decades before it starts looking faded and worn out, stucco has a useful service life of up to 100 years.

Con: It Can Crack

Correctly applied stucco rarely forms anything more than hairline cracks, but this problem does come up often with traditional materials. Newer stucco systems can help to prevent hairline cracks and stress cracks that occur as a result of settling.

Pro: Unlimited Customization

Stucco is an incredibly customizable material. The finish can be highly textured or smooth, tinted with a range of colors, and incorporated into a wide range of architectural styles. Gone are the days when people thought of stucco exclusively in terms of its use as a traditional building material for Southwestern-style homes. Newer systems are found on and in all kinds of structures.

Con: Limited Insulation

Conventional stucco provides little in terms of insulation. This was a problem until recently when contractors began to incorporate insulation systems into their stucco applications to prevent thermal bridging and unwanted heat transfer.

Pro: Reasonable Cost

The cost of installing stucco varies depending on the size of the structure, what kind of system is being used, and how many skilled laborers there are in the area. In places where stucco is common, labor costs tend to be lower because there are more contractors available that have the high level of skill required to apply it correctly. In these areas, stucco tends to be more cost-effective than vinyl, wood, or composite siding.

The Importance of Hiring a Skilled Contractor

Applying and repairing stucco requires a large amount of skill, so homeowners can’t call up just any contractor. They need to work with professionals who have dedicated training and plenty of experience working with the stucco system in question. Proper application is the only way to guarantee the longevity of this versatile material, so take the time to investigate options thoroughly.