EFIS, or Exterior Insulation and Finish Systems is used in place of traditional stucco as an exterior wall system for new buildings and older structures that need a facelift. EFIS is also often used as a way to upgrade or repair existing solid masonry walls in commercial and residential construction. Invented in Europe after WWII, EIFS first entered the United States homebuilding market in the 1970s when it was introduced as a cost-effective solution to retrofit solid masonry structures and later for new single family homes over stud and sheathing framing.
Despite a bad rap in the 1980s and '90s, today's EIFS is one of the most highly tested and researched claddings in the construction industry. EIFS combines the benefits of an insulation system with the attractiveness and durability of a decorative finish such as stucco or cementitious fiberboard (commonly known as fiber cement) siding. Today's EIFS products are fully compliant with modern energy rating systems that stress a continuous insulation and air barrier behind the cladding.
The advantages of using EIFS are many. It is flexible, cost-effective and durable. It can be applied over a concrete or steel stud wall, wood framing, or masonry structures. EIFS is also highly decorative, with many design options available. Architects can use a wide range of colors and textures, and EIFS is especially versatile in architectural details such as rounded windows and doors, arches, bump outs and eaves.
Having said all that, if not properly detailed and installed by experienced applicators, EIFS can be problematic. Moisture can become trapped behind the EIFS with no way out and lead to mold, rot and wood damage. Because of these concerns, many insurance companies attach some form of an EIFS exclusion to contractors' liability policies.