Finding cracks in the stucco of your home’s exterior can be alarming. You may wonder if it represents a construction defect. You should know that stucco cracks normally as a matter of course. Stucco cracking is more common in newer homes because of the materials currently in use. It is only when the cracking becomes excessive that you have a problem that needs attention and may indicate that the builders cut corners.
The size of the crack makes a difference. Anything over 3/32 of an inch represents a problem, but occasional hairline fractures are normal and nothing to worry about. Construction defects can sometimes cause excessive cracking of stucco. Here are some common examples.
1. Stucco thickness
Stucco application to the wall must be at least seven-eighths of an inch thick to be up to code. An application this thick can stand up to greater impacts without cracking. However, it is fairly common for the thickness to range from three-fourths to five-eighths of an inch despite this being a code violation, making cracking more likely.
2. Inadequate moisture curing
Sufficient moisture as the stucco dries is necessary for it to develop the strength it needs to prevent cracking. Unfortunately, sometimes adequate moisture-curing processes are lacking, and the stucco cracks as a result.
3. Crowded plywood
The American Plywood Association recommends maintaining one-eighth of an inch of space between the ends and edges of each panel. This space allows the panels to swell due to exposure to moisture. When there is no space between the panels to accommodate swelling, it can lead to stucco cracking due to outward expansion. This may represent a defect since the sheathing does not follow established APA guidelines.