Stucco Mixing & Applying

Stucco was originated as material meant to give an exterior building texture while also providing it with strength and durability. Over the years, however, stucco has begun to be used in many different ways. It can be used to patch as well as to decorate. It is in its decorative form that stucco has become popular for interior use. Mixed with other materials and color pigments, stucco can wonderful texture and tone to interior walls and furnishings. Stucco is applied a bit differently in each of its many application uses. Below are various ways of mixing and applying stucco products.

Difficulty:

Moderate

Instructions

Mixing Stucco

1. Mix equal parts of cement and lime with two or three parts of sand to make stucco for exterior use. Measure out and mix the product from scratch using either a large tank or wheelbarrow and a stick mixing tool. Add enough water to obtain the consistency ultimately desired. Add color pigmentation if something other than the natural stucco color is desired. Keep mixing until the product appears the same throughout.

2. Mix one part of cement and one part of masonry grade lime to two parts of pure sand and one-half part of masonry grade fiber with enough water to make a thick stucco consistency. Stucco used for patching purposes must be stronger than that used to form the original exterior foundation. The proper ratios of cement, lime, sand, and hair (or fiber) is crucial. Mix the product in a professional mixer to ensure it is thoroughly combined and ready for use.

3. Mix equal parts of cement, lime and sand for interior grade stucco. Add more sand along with paint (colored as desired) as needed to achieve the desired textured look. Add water into the mixture if the mixture appears to be too thick to trowel on properly or if the mixture appears to want to crack easily.

4. Blend pre-prepared stucco mix according to the instructions provided on the bag of the brand chosen. For outdoor applications, it is possible to add color pigmentation to obtain a certain shade or color.

5. Use actual paint for color and thinning for indoor stucco applications. Start with just the addition of paint and put in additional water only as it is absolutely needed in order to achieve the right consistency.

Applying Stucco

1. Apply a bonding agent before putting stucco over an existing exterior of brick, stone or concrete. The bonding agent helps the new stucco adhere to the former surface while reducing the possibility of it cracking or falling apart. Make certain the bonding agent has had sufficient time to dry. Most take somewhere between 12 to 24 hours. Next put on the scratch coat of stucco using the proper tool. Allow the layer to dry partially before troweling on another coat of the product. Keep applying until the desired effect is reached. Keep the stucco damp until the process is completed. This will help to prevent it from cracking in appropriately. Allow the stucco to dry thoroughly before painting or applying any kind of sealant or finishing coat.

2. Apply stucco to wooden surfaces over roof material and metal netting. These give the stucco a base onto which it can cling. This process will move much slower and more deliberately applied than than outlined in Step 1 above. The beginning scratch coat should be applied in a half inch to three quarter inch coat. Let it dry for about 24 hours before attempting to trowel on another coat. Continuously dampen the stucco with a soft mist of water until the job is complete. Make sure the product is dry before adding any type of sealant or finishing coat.

3. Trowel very thin layers of stucco over dry wall interiors after the material has been properly colored either with color pigment or paint. Thin the stucco out if necessary to achieve thin layers no more than about 1/16 of an inch to 1/8 of an inch in depth. Let the first coat to dry thoroughly before applying another coat. Don’t exceed three coats. Allow the interior stucco to dry completely--about 36 to 48 hours--before applying any type of finishing coat or wax.

4. Choose a textured form of stucco application if desired. Typical textures include smooth, wavy lines, stippling, swirled or imprinted. For a wavy lined look, let the stucco dry partially before running a stiff brush through it in a slightly wavy motion. For a stippled look, allow the stucco to dry slightly. Then, using the end of a broom, push the broom into the product to get a stippled effect. For a swirled look, apply the stucco with a trowel in a semi circle motion without going over the same surface a second time. For an imprinted look, allow the stucco to dry about half way. Then push the shape desired into the stucco in any pattern designed.

5. Add a special surface to a stucco finish if desired. For a glossy interior look, use paste wax which is troweled on much in the same manner as the stucco itself. Or burnish a stucco surface by using sandpaper applied either by hand or with a sander on low speed.

Tips & Warnings

• Use protective goggles and gloves while mixing stucco materials.