WHAT IS STUCCO DAMAGE?
What causes ?stucco damage? is really not even ?stucco damage?. In reality, there is no damage to the stucco. Stucco is usually a concrete material that is damaged only by direct stress or impact such as a hammer or foundation settlement. What most people call ?stucco damage? is really damage to the wood framing or studs that are in between the stucco and the interior wall of the house. This damage behind the walls is not damage to the stucco at all. It is very bad for your house.
Your house is meant to be a waterproof ?envelope?. This means that water should not penetrate from the outside. Your house is built with framing or wooden studs. Laid on top of those vertical studs is a protective sheath of material. Today this sheath is usually Tyvek, a white plastic looking material with DuPont and Tyvek plastered all over it. Older houses will have black tar paper.
Over the Tyvek or tar paper or other material is the exterior wall of the house. It could be brick, wood or stucco. Regardless of the material, water will eventually get between that exterior wall of the house and the Tyvek. If it does, then good construction will direct or channel the water down to the bottom ? think gravity ? where the builder has installed some form of ?weep hole? in a brick wall. With stucco, the moisture problems and ?stucco damage? start here.
In a brick wall, the mason can simply not apply mortar in the vertical space between two bottom bricks so that there is a gap or ?weep hole? for the water between the walls to exit.
With stucco, there is no such weep hole so the contractor has to create some form of weeping to let the water exit the interior space. This is where the ?stucco damage? begins. Until recently, building codes in municipalities did not require ?weep screeds? which will create a ?weeping? system. Now these ?weep screeds? are required. Without them or some other form of ?weeping?, water is trapped behind the stucco. Since stucco is very good at keeping water out ? think concrete ? it is also very good at keeping it inside your walls. When it gets stuck behind those walls, it slowly forms wood destroying organisms otherwise known as wood rot. Once that wood rot begins, everytime it rains, those living wood destroying organisms known as wood rot start eating away at the cellulose or wood material in those walls. Massive damage can occur with no sign to anyone on the interior of the home or anyone looking at the stucco.
Sometimes, experienced contractors who have seen enough ?stucco damage? or wood rot behind stucco, can identify probably locations of wood rot. They can also use moisture meters, infrared imaging and other techniques but these are by no means foolproof or infallible.
If you are concerned, get someone who has experience in stucco and stucco repair to look at the house.