Most of the homeowners Stark & Stark represents in EIFS damage cases first informed us that they thought their homes were clad in traditional stucco. This widespread misunderstanding stems mostly from continuing failure by builders and real estate agents to disclose that the builder used “synthetic” stucco, or EIFS, and not traditional “hard-coat” stucco. But, there’s also a simpler and less sinister reason – most people don’t know what to look for.
What’s The Difference Between EIFS and Traditional Stucco?
Materials
A traditional hard-coat stucco exterior system is extremely strong and durable because it essentially covers your home with a layer of rock. Cement stucco is made of sand, a small quantity of lime, Portland cement and water. Basically, it is a fine-grained concrete that is attached to your house using a waterproof barrier paper, galvanized wire mesh and metal flashings (devices that channel water to the exterior of a wall). The stucco’s facade is meant to be a primary barrier, but a secondary or “concealed” barrier directs any water that gets behind the facade to the exterior. This creates a dual barrier to wind-driven rain, snow and ice. Barrier EIFS on the other hand, uses a multi-layer “synthetic” stucco that is much softer than traditional stucco.
“Breathability”
While it has the appearance of stucco and is installed similarly, EIFS has some very different properties. One of the most important differences is that barrier EIFS will not allow water to pass back through its coating in vapor form once moisture gets behind the system. By contrast, traditional stucco is a porous material which will permit moisture to move both in and out of the wall cavity.
Installation
Barrier EIFS is comprised of a base coat and finish coat applied over an EPS board that is attached directly to the sheathing using fasteners or an adhesive. The system provides no avenue for water to drain out once it penetrates behind the EPS board. Traditional stucco, on the other hand, is applied over a wire mesh, and installed with standoffs that allow space behind the stucco for “weeping” of water. No EPS or Styrofoam board is used in a traditional stucco exterior.
EIFS or traditional stucco?
There are a few simple tests that any homeowner can perform to determine whether he or she has EIFS or traditional stucco.
The Knock Test
Go outside and knock on an outer “stucco” wall of your home. If it sounds hollow, there is a good chance you have EIFS. If it feels like you are knocking on a brick wall, it is more likely that you are knocking on traditional “hard-coat” stucco.
The Gap Test
Put your hand under the bottom edge of the cladding near the foundation, assuming that is possible (another common installation error occurs when the EIFS is installed below grade, making this test difficult if not impossible). If you can feel that the cladding comes out away from the foundation 3/4 of an inch or more, chances are you have an EIFS cladding. This is because the EPS board used in EIFS makes the system extend farther away from the wall than a traditional stucco system.
The Penetration Test
Inspect some of the penetrations in the stucco. Since most installers of EIFS do not create the proper joints around penetrations such as light fixtures, gutter straps, or doorbell/intercom devices, remove these items and check for the telltale foam board used in EIFS. If you see the Styrofoam-like board, you have EIFS. Traditional stucco exteriors do not use this element.
Still Not Sure?
If you still are not sure what type of cladding you have, or you have any other questions, you should contact a certified EIFS inspector or a qualified engineer.
