Synthetic Stucco (EIFS) Problems

General information on products installation or manufacturing defects.

We have been watching the news lately with the concern about synthetic stucco homes. How can we tell if our stucco was properly installed and how do we tell if there is a moisture problem behind the stucco.
Synthetic stucco or "EIFS" (Exterior Insulation Finish Systems) has been used on thousands of Atlanta homes. It differs from "real" or "hard" stucco by utilizing an insulated sheathing board and a fiberglass mesh. The finish is a synthetic material made to look like real stucco.
The problem is water penetration, allowed to enter behind the EIFS, does not evaporate and is trapped. The moisture attacks the wood sheathing, and in the worst cases, the wood framing. Many of the moisture problems appear to be around the areas where the EIFS butts against the wood trim and at the roof flashing. Most of the manufacturers have detailed installation instructions, but unfortunately these are ignored by some installers.
Flashing is required where any vertical wall meets the roofing shingles. Flashing is sheet metal that is installed behind the wall material and extends out underneath the roofing shingles. This prevents water from entering the structure at the intersection of the wall and roofing.
Stepped flashing is commonly used at sloped vertical walls to insure any water that runs between the roof shingles and the flashing will be EIFS1diverted out on top of the lower shingles, preventing water from running under the remainder of the shingles. Some of the installers are still using continuous flashing which is not equal. With most sloped roof flashing, water can continue down to the end of the flashing. If this happens, it could run behind the wall covering and into the wall cavity. The end of the flashing must turn out to ensure any water will be diverted to the outside of the wall.
Most homes do not have diverter or "kickout" flashing installed. If your home does not, it would be a good idea to have it installed.
The bottom edge must be finished on any EIFS system. If the system terminates directly on top of the roof shingles, you can be assured it is not properly finished along the bottom. EIFS must be held off of the shingles by 2" (see diverter drawing) to allow proper wrapping of the mesh and finishing of the bottom edge. We see many cases where the builder installs the roof shingles first in order to "dry" in the roof as soon as possible. The exterior wall finish is installed at a later date with the finish actually sitting on top of the roof shingles.
Another common problem we find is improper installation at the exterior wood trim, especially at doors and windows.
Most of the time EIFS is butted directly against the wood trim. A crack EIFS2appears and this could allow moisture to enter. A minimum of a 1/2" joint is required between the EIFS and any dissimilar material. This joint is filled with a foam backer rod and then covered with a good quality caulking or sealant. It would be a good idea to inspect any wood trim to see if cracks have developed. If they have, just caulking over the cracks will do little to seal the cracks in the long run.
When the wall material moves, the caulking will crack. A joint will have to be installed where the caulking will have something to bond to and also the caulking should be thick enough to move with the expansion and contraction without splitting or cracking.
Decks are another area for concern. It is common to have the decks EIFS3simply installed over the EIFS. Any breaks in the finish or around bolts could allow water penetration. The CABO One And Two Family Building Code requires flashing to be installed where any deck is attached to a wood frame structure. EIFS should terminate 2" above the floor decking, again, for the proper wrapping of the mesh and finishing of the bottom edge. The finish may continue under the deck header provide proper cap flashing is installed. This installation will prevent any water penetration into the structure.
When EIFS continues below ground level, any opening in the finish could allow wood destroying organisms, such as termites, to enter through the insulated sheathing into the wood framing.
We often find the bottom lip is not properly finished and the insulated EIFS4sheathing is actually exposed. EIFS should terminate 6" above the finished ground level and the bottom lip should be properly wrapped and sealed. This will allow a visual inspection of any wood destroying organism crawling up the outside of the foundation.
Some of the Pest Control Companies are refusing to issue a "Termite Letter" on any structure that has EIFS or slab insulation below grade.
The only way to tell if moisture has entered the structure is with a special moisture inspection. Most of the inspections consist of punching holes through the finish so that moisture probes may be inserted into the framing. Some new moisture meters are becoming available that can read the moisture, behind the EIFS, without penetrating the surface. Any moisture reading over 20% is cause for alarm. Since the length of the inspection is proportional to the amount of moisture found, the time could vary from 2 hours to 16 hours and the price from approximately $200.00 to $1,600.00.
On July 11th and 12th 0f 1996, the Georgia Association of Home Inspectors held an EIFS Moisture Intrusion Seminar. In attendance were industry experts which included J.B. Graham, the Director of Inspections for New Hanover County, North Carolina where the first problems surfaced. The panel discussed the problems relating to EIFS moisture intrusion and reviewed some solutions.
The first step should be: Have the structure tested for water intrusion. GAHI has developed a Testing Protocol which describes what type of testing is needed and what areas should be tested. The inspector should be able to give the homeowner an accurate idea on how much water infiltration is present and what can be done to correct the problem.
This type of testing is not an exact science. Many people still disagree on what should be done. According to the GAHI Protocol, the following procedures should be followed:
Moisture is present in the wall. Additional caulking at the specific area should be sufficient.
The source of the water intrusion should be identified, if possible. Appropriate corrective action should be taken to stop the entrance of the water. In many cases, a particular detail may be corrected, or additional caulking installed as a satisfactory corrective measure.
This is the fiber saturation point, the level at which decay begins to occur. The EIFS at these areas should be removed so that the framing can be inspected for indications of rot or decay. Any damaged areas should be repaired or replaced as necessary. � This would be a good time to consider retrofitting the entire house to bring it up to current installation requirements. Included would be:
Cutting back the EIFS from all window and door openings, backwrapping and installing sealant joints. This is one of the major areas for water infiltration. The cracks between the EIFS and the wood trim allow water to enter into the framing.
Another problem, that is beginning to surface, is windows that are leaking at the joints in the wood frames. Be sure to seal the entire window frame at all of the joints.
Installing proper flashing at all openings. Flashing is required to prevent water from entering along the tops of all windows and doors.
Installing roof diverter flashing. This is rarely seen in the Atlanta area but is very important to prevent water running down the flashing, from entering the wall cavity at the end of the flashing. The end of the flashing is bent or diverted out of the wall cavity.
Removing any below grade EIFS. This does not represent a moisture problem, but it could allow wood destroying organisms to enter the structure without detection. Part of the concrete foundation should be exposed to force the organisms to build their tunnels on the outside of the concrete where they can be detected.
Owning a home with EIFS does not necessarily mean huge amounts of repairs or high repair costs. In many cases only simple maintenance is required. A professional inspection is recommended for all EIFS structures. If you are interested in having a water intrusion inspection made, contact the Georgia Association of Home Inspectors for a list of inspectors who specialize in this type of inspection. GAHI can be reached at 770-989-2524 or