The threat of leaks might seemingly be the greatest downfall of Exterior Insulation Finishing Systems. The most unfortunate aspect of this notion is that in most cases, the EIFS itself is not the problem. There are many underlying causes that could make it appear that the EIFS is "leaking" when in fact it is not leaking at all. However, if the general public, homeowners or building owners are convinced that the rumours they hear are true, it will cause nothing but frustration and headaches for installers, contractors and manufacturers. Even worse, it can lead to legal action being taken and that dull ache in your head will soon be emanating from your wallet due to the money spent defending something that shouldn't need to be defended in the first place.
Why EIFS can appear to leak
The leaks are usually originating from another source, perhaps the joints and caulking or more often than not, the flashing near windows and doors. Improper installation can also create reasons for leaking to occur. Before these avenues are explored, for you and your wallets sake, as well as the sake of the reputation of the EIFS itself, the thought that the EIFS could be leaking must be removed. The general consensus is that the areas of the EIFS that are most likely to let in water if such a problem arose, are the base coat or finish. However, to reiterate, it's not the material's fault. Improper application, not enough time to cure properly, or improper manufacturing can also result in water intrusion problems.
One can also choose more adept materials when it comes to preventing water intrusion, for example: consider the base coat is the most important component with regards to repelling water. A base coat containing more resin will perform this duty much better than a base coat containing more cement.
Testing options for EIFS leakage
Part of the process in determining if EIFS is up to code or not depends on if it leaks. If it leaks, it's not up to code. Therefore, any situation in which the EIFS is actually leaking where the leaks are not coming from any other source or for any other reason is generally because the EIFS is not up to code to begin with. Some of the following tests are used to see if the EIFS leaks or how much water it will absorb:
If someone wants to see if their EIFS is prone to leakage as a system itself, you can float a sample-sized piece in a tub of water, weighing it before and after to see if any water is absorbed or not. One could also place a sample comprised of only base coat and finished lamina on a table, place water on it and see if the water leaks through to the other side. This type of sample can be created by applying the materials to a piece of insulating foam and then removing it, either by carefully peeling the lamina off or by rasping the foam away. If the latter method is used and water bypasses the finished top coat as well as the base coat, one can remember that on an EIFS wall the foam will still be standing in the way of the water if it were to bypass the base coat in a real-life situation.
There is also the option of conducting a similar test right upon the finished wall if a sample chunk is not available or removing a portion of the wall is not a feasible task.
In France, a device called a RILEM tube has been developed, named after "Reunion Internationale des Labratoires et Experts des Materiaux," their international union of materials and construction experts. The tube is transparent and shaped like an "L", with the smaller horizontal end being affixed to the wall and water being poured in the vertical, larger end. The shape and the size of the tube creates a pressure that will force the water into the wall if it allows it to. Eventually, you will be able to determine if and how much water is absorbed because the change in water level will be visible and can be monitored by checking the measurement notches on the tube. This test is not designed specifically for EIFS, and can be used on all sorts of masonry applications, such as brick, tile, cements and stucco. It is sometimes even used to determine how much spray paint can be absorbed by a material to see if graffiti will be difficult to remove.
EIFS is consistently proving why its reputation is undeserved
Canadian Concordia University has a Building Envelope Research Database literally filled with quotes from industry experts quoted in newspapers, magazines and trade publications on the merits of EIFS. Many even speculate that the negative reputation is spurned on and encouraged by the manufacturers and those who work with competing products.
This information isn't new, and even in the late 1990's industry and trade magazines were publishing the exact same info: moisture intrusion problems are the fault of the installation process and other factors, not the EIFS itself. This just goes to show how deep and long-term the impact of some misconceptions can be.