Exterior Insulation and Finish Systems (EIFS) were first introduced in the United States in the 1960s to be used to build commercial buildings and have since expanded to homes. Even if you don’t recognize the term EIFS, you’ve most likely seen them without realizing it. EIFS can be found on all kinds of buildings such as houses, apartments, grocery stores, government buildings, and more.
What are Exterior Insulation and Finish Systems?
The International Building Code defines an Exterior Insulation and Finish System (EIFS) in chapter 2, section 202 as a non-load bearing, exterior wall cladding system that consists of an insulation board attached either adhesively, mechanically, or both, to the substrate, an integrally reinforced base coat, and a textured productive finish coat. The system may include primers, surface sealers, and accessories such as trim, corner beads, and stops.
EIFS function as a barrier-type system and can help keep moisture from penetrating the external surfaces of the building envelope. A building’s envelope consists of external wall materials and designs that are climate-appropriate, structurally sound, and are aesthetically pleasing. Some types of EIFS rely on an outer barrier to help protect against water penetration, while others are designed to include a secondary drainage plane behind the insulation.
EIFS are a multi-layered assembly typically composed of:
- Water-resistant barrier
- Adhesives to connect the substrate to the insulation
- Insulation board
- Mesh reinforcement
- Base coat
- Finish coat
Why Use Exterior Insulation and Finish Systems?
According to EIFS Industry Member Association (EIMA), EIFS provide many benefits over traditional finishing systems. The benefits promoted by the association include:
EIFS can reduce air infiltration by as much as 55%. With walls being one of the greatest areas of heat/air conditioning loss, improving the insulation of the wall can be beneficial in terms of energy conservation. One study showed that an EIFS cladded building helped reduce energy use by almost 45% over a twelve-month period.
Unlike the traditional stucco, most EIFS are made with 100% acrylic binder which make EIFS resistant to fading, chalking, and yellowing. This allows systems to maintain their original color and means that they will rarely need to be painted.
Even if the surface of the system is scratched, the color will appear the same beneath where the scratch has occurred. It also provides more flexibility, meaning that it is easy to mold around doorways, arches, and other openings. This flexibility also makes the system less susceptible to damage from environmental changes.
EIFS are sustainable, durable, and resilient, and EIFS can achieve high-impact resistance when built with heavier reinforcing mesh. The Federal Emergency Management Agency (FEMA) has recognized the durability of EIFS and has referenced their use for properties that can be threatened by high winds.
Code Compliance for Exterior Insulation and Finish Systems
To comply with building code requirements and customer needs, manufacturers of EIFS and EIFS components have a few options. They can provide test data demonstrating compliance with each relevant section of the building code, which typically includes, but is not limited to, the following standards:
- ASTM E2568 – Standard Specification for PB Exterior Insulation and Finish Systems
- ASTM E119 – Standard Test Methods for Fire Tests of Building Construction and Materials
- ASTM E84 – Standard Test Method for Surface Burning Characteristics of Building Materials
- NFPA 285 – Standard Fire Test Method for Evaluation of Fire Propagation Characteristics of Exterior Wall Assemblies
- ASTM D2247 – Standard Practice for Testing Water Resistance of Coatings in 100 % Relative Humidity
- ASTM E2570 – Standard Test Methods for Evaluating Water-Resistive Barrier (WRB) Coatings Used under Exterior Insulation and Finish Systems (EIFS) or EIFS with Drainage
- ASTM E331 – Standard test method for water penetration of exterior windows, skylights, doors, and curtain walls by uniform static air pressure difference
- ASTM G155 – Standard Practice for Operating Xenon Arc Light Apparatus for Exposure of Non-Metallic Materials
- ASTM E330 – Standard test method for structural performance of exterior windows, doors, skylights and curtain walls by uniform static air pressure difference
- ASTM E2273 – Standard test method for determining the drainage efficiency of exterior insulation and finish systems (EIFS) clad wall assemblies
Alternatively, manufacturers who want to streamline the approval and building permitting process often work with an accredited third-party certification agency to develop a code compliance certification report, such as an ICC Evaluation Service (ICC-ES) Evaluation Report (ESR). Certification reports provide a public-facing summary of compliance for use by engineers, architects, and building officials to help them quickly understand how a product may be used and how it complies with all relevant code requirements.
About ICC NTA, LLC: As an accredited third-party agency and part of the International Code Council (ICC) Family of Solutions, ICC NTA provides code evaluation, inspection, engineering, plan review, and product testing services, as well as independent quality and standards compliance verification for building product manufacturers. With offices, testing labs, and training facilities in Nappanee, Indiana and Bryan, Texas, ICC NTA serves residential and commercial builders, code officials, manufacturers, and suppliers throughout the building industry.
- EIFS Industry Members Association. “About EIFS.” EIMA, https://www.eima.com/eifs. Accessed 06/22/2022.
- EIFS Industry Members Association. “Benefits of EIFS.” EIMA, https://www.eima.com/eifs/benefits. Accessed 06/22/2022.
- Federal Emergency Management Agency. “The 2021 International Building Code: A Compilation of Wind Resistant Provisions.” FEMA, https://www.fema.gov/sites/default/files/documents/fema_international-building-code_10152021.pdf. Accessed 06/27/2022.
- International Code Council. “International Building Code.” ICC, https://codes.iccsafe.org/content/IBC2021P2. Accessed 06/23/2022.