Stucco Cracking – When is it an Issue?

Stucco is a great exterior finish for any home. It gives a sharp, pristine appearance and truly can give your home the curb appeal that you desire. But, of course, nothing great comes easily. Unfortunately, there are a lot of contractors out there who are not experienced in applying this particular cladding, thus causing a lot issues. One issue in particular is cracking.

Some stucco cracking is natural, as it is a porous finish that will absorb water, so seeing minor, shallow lines over the surface of your home is nothing that you should panic about. The appearance of more severe and more abundant lines however, should cause a little more stress.

In order to understand the severity of your issue with stucco cracking, it is important to know some of the reasons that these cracks occur. Here are a few common reasons.

Too Much Sand: Stucco is made up of three main ingredients: water, cement, and sand.  This combination of materials allows for the proper stress and water relief for the material, but getting the proportions wrong while mixing of any or all of these parts can be a fatal error. Using too much sand is the most common mixing error. Using too much sand in the mix weakens the mixture and can cause it to shrink during the drying process which can cause deep, severe cracks the finish.

Coat Thickness: Another common stucco issue is applying inconsistently thick coats of stucco to the home. Although there are one and two coat applications, usually three coat stucco is applied to the exterior of most residential buildings, and making sure that each coat has a consistent thickness across the entire surface of the structure is important. Of course, there are exceptions to this rule, namely the application of stucco around architectural details of the home where the stucco coats can be thicker, but having two sections of a wall with two different coat thicknesses is unacceptable. This creates varied strength within the wall, which in turn causes cracking.

Hydration Issues:  If the stucco is not properly hydrated, or evenly hydrated, it will not cure properly. Each separated coat will act as one coat of stucco which will reduce the strength of the material, causing serious cracking. Hydrating stucco properly is pretty easy; simply flood the surface of the wall after the coat is applied about three times. This will allow each coat to absorb the proper amount of water as it cures so it will not steal the moisture from the coats that come after it.

Applying stucco is a simple process as long as it is done properly. Making sure that you have the proper amount of each ingredient in your stucco mix, applying the coats of stucco evenly, and ensuring that each coat is hydrating is a great way to prevent structural damage later in the life of the home.  If you are noticing cracking, especially severe cracking, in the surface of your home, it might be a good idea to call a stucco inspector. It is always better to be safe than sorry, and calling a stucco inspector will ensure that you are protecting the structural integrity of your home for your future.