Why Does Stucco Deteriorate?
Properly installed stucco can last many decades; at least 40-50 years under normal conditions. But stucco long life can be shortened dramatically by certain influences. Typically, the influence with the greatest impact is moisture intrusion. Of course stucco is designed as a “building envelope” which, by its nature, protects against the rain and other sources of moisture from the outside (like normal overspray from sprinkler systems). In these scenarios, the stucco immediately sheds the bulk of the water, and only minor amounts are absorbed, and that which is absorbed is typically dried out by the sun and breeze – thereby removing the possibility of damage to the stucco system.
Unusual and early deterioration of stucco systems almost always takes place when water finds its way inside the building envelope. Water that enters the system and remains there will be unable to dry out quickly and can do serious damage to all components of the stucco system, including wood framing, metal components like lath, and of course the stucco itself.
Properly installed stucco DOES NOT allow liquid water to permeate its thickness – except for areas with extreme cracking that allows water to pass through the cracks (typical stucco cracking does provide a path for water).
How Can I Reduce Cracking On A Smooth Finish?
When installing a smooth finish it is critical that the usual care be taken to avoid cracking, but in addition to that, in order to minimize the tendency to crack, a fiberglass mesh and basecoat finish can be done prior to the installation of the finish coat. This is the optimum strategy to reduce cracking. This process adds cost to the overall system, but will absolutely improve the resistance to cracking.
Can I Stucco Just The Portion Of My Home That Is Damaged?
Yes. Knowing how to repair stucco is an art-form. Stucco repairs require a full understanding of how stucco reacts under certain conditions. Whether it’s a window patch, a stucco crack, or a serious stucco failure, we have the experience and know how to make the repairs professionally and as economically as possible. Additionally, we have many years of experience and knowledge of how to match existing textures and colors.
Stucco repairs that have been incorrectly carried out can cause additional serious problems going forward. Stucco cracks that permit the passage of water almost always lead to stucco failure. Also if the repairs do not properly address the prevention of water intrusion into the repaired system, stucco failure is again inevitable.
Why Does Stucco Crack?
All stucco will crack, just like all concrete will crack. There are two fundamental types of stresses that cause stucco cracks—internal and external. Internal stresses are due to the natural curing and drying process of stucco, this usually is within 1 to 2 days. External stresses are due to the transfer of outside forces into the stucco assembly. Common examples are at the corners of windows and doors.
Can You Fix Stucco Cracks on my Smooth Finish?
If unacceptable cracking has taken place on a smooth finish, it can be repaired. However, “spot” repairs cannot be done. When repairs are done to smooth stucco, the final step always involves the recoating of the entire wall panel, corner to corner. This can be expensive for large wall panels – the larger the panel, the more difficult the repair.
The optimum method to repair cracks in smooth finish is to use the fiberglass mesh / acrylic base coat method of repair. This should prevent cracks from reappearing, and should minimize future cracking in the area.
Is Stucco Waterproof?
Stucco is water resistant, but not water proof. Moisture can permeate somewhat into the stucco but despite the mistaken belief of certain stucco “experts”, free water or liquid water will not flow through properly installed stucco.
How Then, Does Water Get Inside The Stucco System?
Far and away the most typical source of water intrusion is from roofs, windows, doors, and other penetrations of the stucco. If water enters the interface of those intrusions, this water can end up inside the building envelope, and if unable to promptly exit, can do great damage to the system, and provide a fertile field for mold growth, etc. Water can also enter the system by “wicking up” from the ground in certain instances of improper or obsolete installation, or when site conditions including landscape watering have not been properly managed.
What Can Be Done To Prevent Water from Entering the Stucco System?
The key to preventing water from entering the stucco system is proper installation in the first place. This means that great care was taken to properly waterproof the structure and all penetrations utilizing all of the latest technologies. In the event of failures after the fact all of the following needs to be considered:
1. Roofs: If water is allowed to enter the system because of roof problems, there is nothing the stucco contractor can do to correct. The roof must be first properly repaired, and then the stucco contractor can review and repair the stucco system as necessary.
2. Windows and doors: If there are leaks near windows and doors, the first step to identifying the problem is to rule out the window itself. Isolated testing can be done to make that determination. Once the window or door has been eliminated, the interface between the window and the stucco should be examined. In this event, the likely failure is the gap between the window and stucco that can sometimes allow water penetration through that gap. In that event appropriate repairs can be made with follow-up testing. In some cases the failure may require windows to be removed and reinstalled but not until other less invasive repair methodologies have been deemed ineffective.
3. All other wall penetrations: everywhere there is an exterior light fixture, electrical outlet, plumbing fixture etc., a potential leak point exists. Water damage in proximity to these items can be caused by gaps or openings associated with those penetrations. Evaluation and repairs of these failures can be performed and the problems can be corrected.
Damage To Seaside Properties
Why Do Seaside Homes Experience Greater Exposure To Stucco Damage Than Other Properties?
Though liquid water cannot pass through the cement matrix of stucco that has been properly installed, moisture (as opposed to liquid water) can permeate to some degree into this matrix – especially when driven by horizontal winds from the sea. Winds that come from the sea can be salt saturated causing chlorides to enter the matrix allowing the chemical reactions from the chlorides that cause the metal lath and accessories to experience accelerated corrosion, and the cement stucco matrix to deteriorate and loose strength.
What Can Be Done To Reduce Early Deterioration Of Seaside Properties?
For new stucco systems, new components that can be substituted for the old more vulnerable components have been introduced into the market. These products include lath that is made of fiberglass, new corner bead and weep screeds that are made of vinyl. Additionally, finish coat systems that are acrylic based can be substituted for conventional stucco finish coat. These acrylic based finish coat systems can completely prevent moisture from ever entering the stucco matrix and the result can be a profoundly longer life for the stucco system in these vulnerable areas.