Numerous things cause cracking of stucco and often it can be very difficult to discover the exact cause and in fact it often a STACK EFFECT with multiple issues causing the cracking. Concrete just cracks so even if everything is installed right you may get a few cracks even on the best application.
Cracking can occur for multiple reason listed below but not limited to list items:
- A lack of expansion/control joints at each penetration such as doors, windows, gable vents, etc.
- Expansion/control joints improperly installed such as continues over the metal lath.
- The wood substrate is improperly installed and is creating issues with movement.
- Foundation settlement/movement.
- Stucco plaster improperly installed in each coat (scratch coat, brown coat, etc.
- A lack of watering/hydration of the plaster coats.
- Water penetration into the wall causing the underlying wood materials to warp or deteriorate (very common cause)
- Stucco installed on hot walls that are not properly ventilated such as on an unventilated garage that heats up on the inside of the garage and the outside of the garage.
- The metal lath improperly installed/secured.
- The use of such things as light gauge wires/chicken wires.
- To thin or to thick coats of stucco being applied at one time.
- Not allowing proper cure time between each coat of stucco being applied.
- Not keeping the plaster hydrated properly as the stucco application is curing.