Just like other problems with stucco or any other siding for that matter leaks occur for a multitude of reasons and are often multiple different leaks (STACK EFFECT) not just attributed to a single item. Caulks and Elastomeric paints are not a fix to the underlying leak issues all though a good salesman contractor will try to convince it is. Stucco is a water resistant decoration detail just like all other sidings, this is a building not a submarine and water WILL enter behind all sidings and you are dependent to your WATER MANAGAMENT SYSTEM.
The items listed below are not all inclusive of the issues that cause leakage but will give you some ideas as to some major causes of leakage:
- Lack of head flashings above windows.
- A lack of head flashings above doors.
- A lack of pan flashings of doors.
- A lack of flashing between the stucco and say stone, brick or fiber cement siding.
- A lack of a weep screed flashing at the base of the stucco.
- A lack of a drainage plane/weep screed at the roof line.
- Weep screed improperly installed above the foundation line.
- Damaged weather resistant barrier (WRB).
- Windows improperly installed with proper flashing details to the WRB.
- Doors not flashed to the WRB
- Gable vents not head flashed.
- Decorative plaster bands improperly installed.
- A lack of flashing at penetrations through the WRB such as water pipes, electrical, vent pipes, etc.
- A lack of a 2 layers of WRB/bond break.
- Head flashings lacking proper end dam’s at penetrations such as doors and windows.
- A lack of a rain screen/drainage plane behind the plaster.