The problems with barrier EIFS cladding all stem from water intrusion. These problems include moisture accumulation in the wall cavity, subsequent wood damage and, in more advanced cases, mold growth and the infestation of pests such as carpenter ants or termites.
Moisture Accumulation In The Wall Cavity
Contrary to some reports, water intrusion problems with EIFS are not unique to any part of the country. While the problems with EIFS were first discovered in Wilmington, North Carolina, this in no way means that you could not have similar moisture intrusion problems where you live. Field investigations of barrier EIFS in other areas of the country have identified excessive moisture accumulation problems in New Jersey, New York and Pennsylvania. Simply put, the more it rains, the greater the likelihood of water intrusion problems.
There are many sources of water intrusion in barrier EIFS, including improper joints around penetrations, improper joints where EIFS meets dissimilar materials, and lack of proper flashings. Water can also enter the system through cracks in the face of the EIFS, regardless of how small the crack. Essentially, any joint or penetration in the EIFS material may be suspect.
When water enters behind the EIFS on an ongoing basis, there is little chance of the system ever drying out. Elevated moisture levels (over 20%) lead to wood decay and fungus which is often visually undetectable. The result can be saturation, wood rot and serious damage to the wood structure.
The moisture behind a barrier EIFS cladding creates a perfect environment for many pests. In addition, the EPS foam panels used in EIFS offer an ideal home for insects, especially carpenter ants and termites.
EIFS carpenter ant infestation can be more difficult to treat than usual ant problems. Because of the saturated foam board and elevated moisture content in the wood, carpenter ants tend to remain within the structure of the home and do not migrate to the exterior. As a result, pesticide treatments around the foundation of the home are less effective. Also, traditional powder treatments often fail because the powder “cakes” when it contacts the saturated wall cavity, reducing its usefulness.
Termites also present unique problems in EIFS, as they are virtually undetectable in the foam panels used in EIFS, which can be up to four inches thick. Termites prefer to tunnel inside the material as they migrate from the ground to the wood structure and back to the ground. Some experts suggest that termites like the elevated carbon dioxide levels found in the boards, and the relative ease of tunneling through the damp panels. Many pest control professionals actually recommend moisture intrusion tests be performed by specialists to determine if a problem exists before they will even inspect the home.
Molds will grow anywhere where there is moisture. This is especially true given the vapor impermeability of EIFS, which creates an ideal environment for the growth of molds including Cladosporium, Penicillium, Aspergillus, Alternaria and one of the more toxic molds gaining media attention, Stachybotrys Chartarum (also known as Stachybotrys Atra). Constant moisture, a problem with barrier EIFS, is required for Stachybotrys Chartarum to grow. While it is less common than other mold species, it is not rare.
Mold exposure does not always present a health problem. However, some people are sensitive to molds. These people may experience mild symptoms such as nasal stuffiness, eye irritation, or wheezing when exposed to molds. Some people however, may have more severe reactions, including fever and shortness of breath. People with chronic illnesses, such as obstructive lung disease, may even develop mold infections in their lungs.
What To Look For If You Have EIFS
Because barrier EIFS cannot drain water, the system’s success depends heavily on a perfect installation job — something rarely attained. Common installation errors include inattention to detail when sealing openings, failure to properly “backwrap” the mesh at termination points, and failure to use proper flashing.
Here are some areas around the home most susceptible to water intrusion:
- Joints around windows, door frames and sills or where the EIFS meets other materials such as wood trim, stone or brick
- Areas where roof lines intersect with the EIFS, or anywhere diverter flashing or step flashing is missing
- Deck connections
- Decorative trim which is butted against or nailed through the EIFS
- Fireplace chimney chase
- Cap flashing and cricket flashing
- Any penetration in the EIFS, such as utility lines & pipes, hose bibs, screws and nails driven through the EIFS, A/C refrigerant lines, exterior light fixtures and receptacles, etc.
- Expansion joints between floors
- Any horizontal surfaces where water can pond
- Cracks or damage in the finish coat of the EIFS