Exterior Insulation and Finish System (EIFS) is often thought of, and is sometimes described as, stucco. EIFS is not stucco; it is a proprietary wall covering system that looks like stucco.
Two EIFs systems exist. (1) The barrier system relies on installing all components exactly according to manufacturer’s instructions, and relies on these components remaining sealed against water entry. Barrier systems are no longer allowed in many jurisdictions. (2) The drained system relies on the traditional combination of a water-resistive barrier and penetration flashing to provide a secondary drainage system for water that infiltrates behind the EIFS.
EIFS should be installed by applying a one layer synthetic finish coat over a fiber reinforced synthetic base coat applied on insulating sheathing that is attached to structural sheathing. A drained system adds a water-resistive barrier and integrated flashing between the structural sheathing and the insulating sheathing. EIFS has been available since the 1960s, and was most popular from the late 1970s to the early 1990s. It is still available and used today. EIFS is sometimes referred to by the brand name Dryvit® after the company that first introduced it in the North American market. It is not correct to use brand names to describe materials.
EIFS should be installed according to manufacturer’s instructions. These instructions may vary based on the manufacturer, the type of system being installed, and the location of the house.
Older (barrier) versions of EIFS are a known problematic wall covering. Many of the problems experienced with this wall covering were caused by improper installation. Evidence of moisture intrusion is often concealed; therefore, evaluation and invasive moisture testing by an EIFS specialist is a prudent recommendation, especially for barrier systems installed before the early 2000s. Class action lawsuits alleging product defects were filed against many manufacturers of this wall covering. These lawsuits were settled, and the recovery funds were exhausted many years ago.
Typical Defects Typical defects that home inspectors should report include:
Standards (1) IRC 2018 Section R703; (2) manufacturer’s instructions (must be followed precisely).