Are you considering a stucco finish for your new home or existing home remodel?  Are you having trouble following the difference between stucco, plaster, and mortar?  When you hear people and professionals talking about building materials do you find yourself getting a bit lost trying to keep up with the vocabulary?

What is the difference between stucco, plaster and mortar?  Basically the difference is based on use, rather than composition.  Plaster used to be the most common building product and stucco was used mainly outside.  They are made of the same material, lime and sand.  Mortar is also made of this material. 

During the later part of the 19th century, animal or plant fibers were added to the material to increase the strength.  Portland cement was eventually added to help increase the durability, while at the same time gypsum plaster replaced the lime plaster.

Stucco has followed suit, as it is now made up of Portland cement, sand and water.  Lime is only added to decrease the permeability but to increase the workability of stucco.  Acrylics and glass fibers are sometimes added to improve the structural properties of the plaster, which is commonly known as a one-coat stucco system.

Stucco is usually applied in three coats—the scratch coat, the brown coat and the finish coat, which can be applied by hand or sprayed.  A trowel can be used on the finish material to smooth and hand-texture it by a sand finish or sprayed.

In some of the southern states, such as California, Arizona, New Mexico and Florida, stucco is a predominant exterior in both residential and commercial construction.  Stucco is also used as a sculptural and artistic material, such as found in places like churches and palaces.  Baroque and Rococo architecture uses stucco quite a bit. 

The scratch coat is applied with a brush to give the surface a crisscross pattern, providing the key for the second layer.  The second layer is the brown coat.  The mixture of sand, cement and lime is leveled with tools called rods, darbys and federege.  They are then scraped smooth and floated to give a smooth finish.  The curing period takes approximately between 7 -10 days.  If the stucco is applied during very dry weather,  it is recommended that the layers of stucco are sprayed with water for one or more days in order to keep the moisture level within the stucco while it cures.
The final layer is called the finish coat.  There are two types that are recommended.  The first is a color coat where a colored sand, cement and lime mixed finish is applied over the second coat.  The second is an acrylic finish, which is the most recommended finish as it is a longer-lasting quality and can come in any color.

Although no longer recommended, hard coating is another method for finishing a stucco wall.  This was used mainly during the 1960s and 1970s where glass chunks, stones or marble was added to the wet stucco wall.  This is no longer used very much because it is heavier, inflexible and hard to repair. can connect you with quality stucco contractors or general contractors who can consult with you on the needs for your home improvement or home construction project.

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