Artificial stucco can be, and more often than not is, a problematic exterior cladding. We have inspected hundreds of houses with this material and have yet to find a single one that does not have significant moisture intrusion issues. Even the National Association of Homebuilders, normally a champion of anything in the residential construction arena, has dubbed the material as inherently defective.
EIFS, or Exterior Insulated Finishing Systems, (sometimes referred to as “synthetic stucco”) are wall systems that incorporate insulation with the exterior cladding and were invented in Europe after 1947. German engineers formulated a variety of materials utilizing polymer chemistry around the same time. These modern materials were based on plastics technology and were soon brought together to form what is known as an EIFS wall system.
Use of the product became very popular due to its physical, aesthetic and economical characteristics. The rebuilding of Europe after the Second World War spawned widespread usage of these systems that worked well with construction standards at that time. Typical construction of residential dwellings in Europe consisted of a masonry structure and then the application of an EIFS wall system. The first commercial producer of EIFS in Europe was the Sto Corporation.
The first project in the United States was begun in Rhode Island in 1969. The introduction stage lasted up until about 1976. During this time, one company, the Dryvit Co., manufactured and marketed the product in this country. Application was primarily in the commercial market.
From 1976 to 1990, substantial growth occurred in this industry. Additional competition entered the marketplace and projects were completed which received national attention from industry press. The manufacture and installation of EIFS wall systems were becoming known as an industry and there was significant development as a result of increased competition.
Today EIFS buildings account for nearly 17% of the commercial market and about of the 3% of the residential market.
EIFS is a non-load bearing exterior wall finishing system that gives the building a stucco-like appearance. The system typically consists of four components:
- Panels of expanded polystyrene foam insulation glued and screwed to the substrate or vapor barrier.
- A base coat that is troweled over the foam insulation panels.
- A glass fiber reinforcing mesh that is laid over the polystyrene insulation panels and fully embedded in the base coat and.
- A finish coat that is troweled over the base coat and the reinforcing mesh. The base coat, mesh and finish coat are usually 1/8 to 1/4 of an inch thick. This is also called the lamina.
There are two basic types of EIFS currently in use in this country, barrier and water-managed (or drainage). Barrier EIFS is designed to divert all water from the exterior surface. Water-managed EIFS assumes that some water will penetrate the surface and incorporates redundant water-management features (flashing, weeping, drainage plane and water-durable substrates) to ensure that water that penetrates the exterior finish will quickly exit the system. Most EIFS clad homes in the U.S. are barrier EIFS systems.
The advantage of EIFS as a finishing system is that it is energy efficient and economical to install. Regrettably, barrier EIFS systems have been found to have problems, often severe, with moisture intrusion, the overwhelming majority of which are due to poor installation practices by installers. In 1995, building inspectors in Wilmington, North Carolina discovered severe moisture damage on hundreds of EIFS clad homes in that area. Similar problems have since been discovered on EIFS clad homes in other parts of the country, resulting in class action lawsuits against the EIFS manufacturers. In some cases, removal of the EIFS cladding has revealed extensive water damage to the framing, compromising the buildings’ structural integrity.
Because the EIFS system is practically watertight, water that penetrates behind the EIFS sheathing does not readily evaporate. The barrier EIFS system is designed to allow for small amounts of water vapor, but the system does not allow larger amounts of moisture to readily evaporate. Water can become trapped and can be absorbed into the substrate and framing. Unlike more traditional facades, there is normally no secondary barrier (housewrap or building paper) installed behind the EIFS to protect the sheathing or framing. Severe damage could occur without any exterior signs. These problems can exist regardless of the age of the building or the quality of construction. Some of our inspections have revealed extensive damage to buildings’ substrate and framing, of which the homeowners were completely unaware. If problem areas are identified, preventative measures can be taken before damage occurs, or before it becomes extensive enough to jeopardize the structural integrity of the building. Early detection and prevention of moisture intrusion can save thousands of dollars in repairs later on.
Water does not usually enter through the EIFS system itself, but through penetrations in the EIFS. The most common areas of moisture intrusion are around windows and doors, at the intersections between the EIFS and the roof, and areas where the EIFS has been penetrated by attachments such as mailboxes, shutters, decorative molding, roof gutters, railings, deck attachments, vents, chimney caps over EIFS clad chimneys, and utility lines and pipes, et al. Meticulous attention to the EIFS manufacturer’s installation instructions is essential to prevent water intrusion. EIFS systems also depend heavily on sealants to keep moisture from getting behind the system. If the sealant is improperly installed, of the inappropriate type, decayed, damaged or missing, water intrusion may occur. Moisture intrusion may also occur if the EIFS itself is cracked or damaged.
An EIFS moisture inspection is intended to identify installation defects, locate areas of high moisture content in the sheathing and framing, to identify areas where the substrate has already been damaged by water, and to identify areas of potential moisture intrusion. Often, an EIFS moisture inspection will detect leaks that are not related to the EIFS system at all. For example, our inspectors have located plumbing leaks, roof leaks and leaks from shower and bathtub enclosures during EIFS inspections.
There are standard inspection protocols governing EIFS inspections, but each building must be evaluated independently. The nature and scope of the inspection may change according to what is discovered. The inspection of the average house takes about 2 hours, but may take several hours, and may even span more than one day.
Before the inspection the buyer, homeowner, Insurance Company, or other client is asked to detail what specific areas of concern should be addressed, any problems that have been seen, and other information about the building. When the EIFS inspection occurs as a result of a real estate sale, the EIFS inspector should coordinate with the home inspector and the termite inspector to share information and findings. After the inspection, a customized 60 – 100 page report is prepared for the homeowner or client, including recommendations about maintaining an EIFS building to minimize the risk of water damage.
In a standard EIFS inspection both an infrared camera and a non-intrusive moisture scanner (Tramex Wet Wall Detector®) are used to identify areas of probable high moisture content. In areas where the scanner indicates high moisture content probability a probe moisture meter (Tramex® Professional Moisture Meter for Wood) is inserted to test for the moisture content of the substrate and to test for damage to the substrate. The probe moisture meter is also used at random locations throughout the system, and in areas where potential moisture intrusion typically occurs, such as near windows. High moisture content in the probe reading indicates that water intrusion has indeed occurred, and may be causing structural damage to the building. If the probe indicates that the substrate is soft, this could be a sign that significant damage has already occurred. The probe moisture meter will make two small ice pick-sized holes in the EIFS contained within the diameter of a dime, which are then sealed by the inspector with an industry-approved sealant.
If the probe moisture meter indicates high moisture content, or if areas of soft substrate are found, it may be necessary or advisable to conduct a more invasive inspection. This will involve removing sections of the EIFS to physically inspect the substrate or framing. Sometimes significant damage is discovered, which, if not repaired, could jeopardize the building’s structural integrity.
THIS IS EXTREMELY IMPORTANT: Any inspector who suggests to you that a proper EIFS inspection can be formed without the use of a probe moisture meter is either woefully misinformed or downright dishonest. Nothing could be further from the truth. The nationally accepted protocols are set forth by the EIFS Review Committee (ERC) of the New Hanover County Inspection Department of Wimington, NC, and the Georgia Association of Home Inspectors (GAHI). Both protocols specify the use of probe moisture meters as an integral and crucial part of the inspection process.
Annual inspections of EIFS buildings are recommended by most insurance companies and the industry, including all of the systems manufacturers and the National Association of Home Builders, to minimize the risk of serious damage and to identify potential problems before they become serious.