Figures 1 and 2 illustrate the respective components and definitions of EIFS and EIFS with Drainage systems based on provisions which have been in the IBC/IRC since 2009. EIFS are the original systems introduced in the United States more than 50 years ago and are often referred to as barrier or face sealed systems in that water is managed at the exterior face. EIFS with Drainage were introduced circa the 1990s and incorporate the same components as EIFS plus they ‘add’ a water resistive barrier (WRB) and means for drainage. Similar to other drainage type wall systems and products, EIFS with Drainage incorporates a mechanism for incidental moisture to be collected on the WRB, flashings, etc. and exit.
Both the IBC and IRC contain specific language and requirements for each system type. Below is a very simplified description of when EIFS with Drainage is required. Refer to IBC Section 1407 and IRC section R703.9 for a complete set of provisions and requirements.
2024 International Building Code (IBC)
EIFS with Drainage – required on framed walls of Type V construction, Group R1 R2 R3 and R4 occupancies.
2021 International Residential Code (IRC)
EIFS with Drainage – required over all substrates except for concrete and masonry.