Why Use Stucco For My Home?
Stucco has been used in architectural structures since the Greek and Roman era and during the Renaissance. It spread throughout Europe and gradually became popular in America. Stucco is a finishing plaster composed of sand, lime, water and other ingredients. It is a strong, attractive and damage resistant covering for walls and ceilings. It is an excellent building material for hot areas as it helps to regulate the temperature. It is non-combustible and its surface burning properties include no flame spread and no smoke development.
Currently, there are two distinct types of Stuccoes –
Traditional/Hard Coat Stucco – This is basically cement mixed Stucco. The traditional stucco is durable and able to withstand harsh environments. It is porous and can breathe, so, dries quickly and resists water damage.
Conventionally, lime was used with sand and water. As lime is slightly soluble, the mixture has a self-healing tendency. At present, stuccoes are usually made up of Portland Cement, sand and water resulting in a hard and brittle variety.
To install hard coat stucco, first the substrate is installed followed by a metal lath and then a coat of stucco is applied with a trowel. It is allowed to set and then another coating is applied. Normally, the process involves a scratch coat, a brown coat and a finish coat (may be colored).
Stucco can also be applied on a paper and wire. The coats should be thicker. The first coat (scratch coat) covers the wire. It needs to be scratched as soon as it sets. The second coat (brown coat) gets bonded to this coat and as usual the finish coat is the outermost layer.
Synthetic Stucco – Since 1950s, a number of houses were built using a variety of synthetic materials resembling stucco. Fibers and synthetic acrylics were added to the cement stucco mixture to add strength and flexibility. In general though, the synthetic stuccoes are less heavy and hence, more susceptible to a hard blow. They are a one-coat stucco system unlike the three-coat traditional ones.
The most common one is EIFS or Exterior Insulation & Finish Systems. They are glued or mechanically attached to the substrate and usually composed of three layers. The innermost layer, mostly made up of polystyrene like material, is a foam insulation board. The second layer is a base coating attached to a fiberglass mesh and the final layer is a finish colored coat. It became popular because of its easy installation, low cost and better insulation properties. The only disadvantage is moisture absorption which causes water damage to the building.
A variety of stucco colors/paints are available. Colorants are inorganic pigments which can adapt with the high pH value of cement. They can be either natural like, Ochers and natural earths or artificial, such as man made Iron Oxides. Natural colorants remain unaffected to UV rays and are more pleasant to our eyes. But, the range of shades and the tinting strength is less when compared to manufactured colors. Man made colors, on the other hand, offer a wider range of shades such as dark blues and greens as well as various earthy tones like, yellow, brown and reds. They also possess excellent UV stability due to the presence of inorganic pigments.
How to Repair Stucco
There are three common types of stucco finishes you might choose from when applying the exterior wall to your home. These finishes include wet dashes, dry dashes, and float finishes.
The wet dashes include many different variations of stucco finishes you might choose to apply to your home. These finishes include the rough cast, pebble dash, spatter dash, broom dash, and even the sand dash. The pebble dash or the rough cast is simple to obtain by throwing the mixture on to the wall by using a paddle. The mixture will include grout and pebbles. You will throw the mixture against the fresh coat of mortar.
The spatter dash can be obtained in a similar fashion but instead using a thinner mixture of cement and coarse sand. Some people choose to use stone screenings instead of sand. This mixture is dashed against the mortar. The sand spray and the broom dash mixtures are used by actually applying the mixture to the mortar by using a long fiber brush or a whisk broom. You do not throw the mixture but apply it. The reason these finishes are called wet finishes is because you apply the finish to the mortar while it is still fresh.
The dry dash stucco finish is another common finish people prefer on their house. When obtaining the dry dash look, you will throw clean pebbles, pieces of shell, or even stone chips against the mortar right before it is hardened. It is important to try to uniformly distribute the mixture across the wall so the outcome looks nice. In most cases, you will have to push the pieces of rock into place by using drywall finishing tools like a float. However, you should not rub the surface once the pieces are embedded into the mortar. The dry dash is a more difficult finish to apply because it takes more time and you have to be more careful to evenly distribute the rocks and pebbles.
Float stucco finishes are another popular option to use on the exterior wall of a home. This type of finish is accomplished by applying the coating once the mortar has begun to harden. This type of finish requires a thin finish coat and needs to be straightened before you begin floating. Once the stucco has begun to stiffen, water needs to be dashed on the surface with a brush. Float finishes are performed by professional workmen with experience and skill. Not many homeowners attempt to do this type of finish on their home.
There are three different types of stucco finishes you might choose from if you are looking for a new siding for the exterior of your home. These types of finishes include wet dashes, dry dashes, and float finishes. Wet and dry dashes are the most common if you are thinking of performing this project on your own. If you would like a float finish on the outside of your home and you have never done this before then you might consider hiring a professional to assist you.