EIFS FAQs. General. What does EIFS stand for? EIFS is the acronym for Exterior Insulation and Finish Systems. What is the definition of EIFS?

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1 EIFS FAQs These comments are for general information only and are not intended to be relied upon as a guide for design, constructions, or inspections of EIFS. Although every effort is made to ensure that this information is timely and correct, the responsibility remains with the designer, specifier, homebuilder, general contractor, and/or installer for specific applications. The specification, design, and construction of all EIFS must comply with local building codes and standards, applicable compliance reports and the individual manufacturer s system requirements. The successful performance of EIFS cladding is dependent upon the proper design and construction of the adjacent materials and systems of the structure. What does EIFS stand for? General EIFS is the acronym for Exterior Insulation and Finish Systems. What is the definition of EIFS? According to the definitions contained in the International Building Code and ASTM International, an Exterior Insulation and Finish System (EIFS) is a nonload bearing, exterior wall cladding system that consists of an insulation board attached either adhesively or mechanically, or both, to the substrate; an integrally reinforced base coat; and a textured protective finish coat. EIFS typically consist of the following components: An optional water-resistive barrier (WRB) that covers the substrate The drainage plane between the WRB and the insulation board and is most commonly achieved with vertical ribbons of adhesive applied over the WRB. Insulation board typically made from expanded polystyrene (EPS), but can also be XPS or polyisocyanurate. An insulation board is attached with an adhesive or mechanically to the substrate Glass-fiber reinforcing mesh embedded in the base coat A water-resistant base coat that is applied on top of the insulation to serve as a weather barrier A finish coat that typically uses colorfast and crack-resistant acrylic co-polymer technology When were EIFS invented? In 1952, the first patent was granted for expanded polystyrene insulation board and in this same year, the first synthetic plaster was developed. In the late 1950s, EPS and synthetic resin materials were first used together. In 1963, EIFS were first marketed in Europe, and in 1969, EIFS were first introduced in the United States. They were first used on commercial buildings, and later, on homes.

2 Are EIFS in the building codes? Since 2009, the International Building Code and International Residential Code, both published by the International Code Council, provide for, within the code itself, the use of Exterior Insulation and Finish Systems (EIFS). Do EIFS require expansion joints? Expansion Joints and Sealants Expansion joints in EIFS are required at the following locations: where they exist in the substrate or supporting construction where the EIFS adjoins dissimilar construction or materials at changes in building height or other areas of anticipated building movement at floor lines in multi-level wood frame construction where prefabricated panels abut one another where the substrate changes How wide should expansion joints be when installed with the EIFS? This issue is the responsibility of the design professional. Can a V groove reveal be considered a joint? A V grove reveal is aesthetic and cannot be considered a joint since a true joint is a built-in break in the system where movement of the wall is anticipated which can result in cracking. Reveals in EIFS are strictly aesthetic and are used to provide convenient stopping points for finish application in large wall areas. If movement relief is necessary, a full expansion joint with sealant is necessary. The term control joint is not used in the EIFS industry. Is it necessary to install sealants? Yes. Sealants are always required around windows, doors, all service openings, and at the juncture of dissimilar materials. This is true for every type of wall cladding. Sealants are not a part of the EIFS system; however, their use in conjunction with the system is a necessity. Moisture damage caused by failure to properly apply sealants at those points just named is not covered by manufacturers warranties. Are there alternatives to applying sealants around my windows? No. The sealants around the perimeter of your windows, and the sealant around doors, dryer vents, house bibs, and every other service opening serve a critical function; they help keep your home tight and help in keeping water out of your walls. If the sealant is properly installed as specified by the sealant manufacturer, these can give you many years of protection. Why must a closed cell backer rod be used with EIFS? The use of closed cell backer rod (instead of open cell) behind sealants is recommended to prevent premature failure of the sealant joint. Open cell backer rod will absorb and hold water that could affect the sealant/eifs bond line.

3 Design Considerations Do EIFS have a fire rating? EIFS alone do not have a fire rating. Testing has been performed to confirm that the fire resistance of an already rated wall assembly is maintained and is not reduced by the addition of EIFS. EIFS have passed the major fire resistance tests that are required by the building codes. EIFS have passed fire resistance, ignitability, intermediate multi-story (NFPA-285), and full scale multi-story corner tests; meeting and surpassing the standards set forth with each test. Should EIFS be applied below grade? No. Building codes have criteria for minimum separation of siding materials from grade. EIFS manufacturers generally require that EIFS be maintained not less than 6 inches above finished grade to ensure code compliance. Is mechanical attachment of EIFS recommended to resist high wind loads? No. In general, adhesive attachment of EIFS to sound supporting construction provides superior wind load resistance in comparison to mechanical attachment. It is important in an adhesively attached system that the supporting construction is free of surface damage, defects, or contamination. In the case of frame construction, sheathing must be attached with fasteners with the spacing of the fasteners so they are capable of resisting wind loads. Isn t EIFS easy to crack or break through, meaning it s not durable? The systems are designed to be very flexible, which makes them highly crack resistant. When walls expand or contract due to rising or falling temperatures, EIFS are resilient enough to absorb building movement and thus avoid the unsightly cracking problems that are so common with stucco, concrete and brick exteriors. EIFS have passed the stringent Miami-Dade County Hurricane Test, showing no impact against hurricane style weather. EIFS have passed the major fire resistance tests that are required by the building codes. EIFS have passed fire resistance, ignitability, intermediate multi-story(nfpa-285), and full scale multi-story corner tests; meeting the standards set forth with each test. What are the limitations for usage of EIFS in high wind load areas? Independent testing has been performed to determine the ultimate strength of a manufacturer s adhesives to various substrates. The average tensile bond strength was determined to be approximately 20 psi, which converts to 2880 psf. It should be evident that adhesively applied EIFS provides bond strength well in excess of what is needed for virtually any project. The design variables to achieve higher wind load resistance occur within the substrate system and area the responsibility of the project designer. Is greenboard a suitable substrate for EIFS? No. Gypsum wallboard in compliance with ASTM C 630, often referred to as greenboard (because it has a green paper facing on one side), is an interior wallboard commonly used in wet areas such as bathrooms. Suitable gypsum board substrates for EIFS are gypsum sheathing in compliance with ASTM C 1396 (formally C 79), glass-mat gypsum sheathing in compliance with ASTM C 1177 (Dens-Glass Gold or BPB GlassRoc)), and gypsum fiber panels in compliance with ASTM C1278 (Fiberock Brand, Aqua Tough ). The sheathing manufacturer s instructions should be followed with respect to handling and installation.

4 What determines the use and location of a vapor retarder in a wall assembly? The selection and/or location of a vapor retarder is project specific based on numerous factors including climate, wall components, etc., and as such is a design consideration that is the responsibility of the design professional. Is flashing required with EIFS? Flashing and Building Envelope Design Yes. As with all wall claddings, flashing is an important component required by building codes. At points where water can enter the wall, flashing should be directed to the exterior face of the wall. Openings for windows and similar through-wall penetrations require jamb, head, and still flashing to direct water to the exterior face of the cladding. What are the most common entry points for water in building envelope walls? As with all claddings, the most common water entry points in a wall are through or around windows, transitions from roof to walls, and transition from wall claddings to doors and chimneys. This, coupled with improperly installed or missing flashing and sealants, can allow water to penetrate behind EIFS, or any other cladding, and into the wall cavity, where it can potentially cause moisture damage. Is EIFS more vulnerable to damage from moisture intrusion than other wall claddings? No. Moisture intrusion is a potential threat to durability of materials in all exterior wall construction, regardless of cladding type. Moisture intrusion should be avoided by following sound design and construction practices mandated by building codes. Are EIFS permeable? Yes, but depending on the manufacturer and the product selected, the EIFS vapor permeability may vary. When requested, the EIFS manufacturers can perform a Water Vapor Transmission Test for specific walls to evaluate the tendency for condensation to occur. What is EIFS with drainage? EIFS with drainage is conventional EIFS installed over a water-resistive barrier, with provisions (vertical drainage channels) for discharging of incidental water that may enter behind the insulation board. In the event of a breach of the EIFS, the drainage path for moisture exists behind the EIFS to drain water to the exterior. Is a water-resistive barrier required prior to installing EIFS in residential construction? EIFS manufacturers recommend the use of water-resistive barriers over moisture sensitive substrates to provide additional protection in the event of a component failure. Local building codes will stipulate whether this is a requirement or not. What types of warranties are available with EIFS? Maintenance and Warranties

5 A variety of warranties are available, depending on the system installed and per the manufacturer s requirements. Samples of the warranties are available on request from the EIFS manufacturer. What type of maintenance is required for EIFS? Unlike wood, stucco and other siding materials, EIFS rarely need painting. Most EIFS systems are specifically formulated with 100% acrylic binder, which gives EIFS superior resistance to fading, chalking and yellowing. As a result, the systems tend to maintain their original appearance over time. Periodic maintenance should include thorough checking of the flashing and sealing to ensure that the building envelope remains watertight. Damaged or missing flashing should be repaired or replaced immediately; likewise, cracked or deteriorated sealants should immediately be repaired, or removed and replaced. How can you clean the finish coat? EIFS manufacturers provide procedures for cleaning specific systems. Periodically, EIFS finishes may need to be cleaned to remove dirt, algae (usually green stains on the surface of the finish), or mildew (generally black stains that look like dirt) that can accumulate on the surface. Basically, mild cleaning detergents, and low water pressure cool water, and a soft bristle brush. DO NOT USE THE FOLLOWING: cleaner that is solvent based; high water pressure; hot water; or wire brushes. What materials can I use to recoat my EIFS? For situations where you might wish to change the color of the building, or paint the building for some other reason, EIFS manufacturers produce several quality paint products (acrylic or elastomeric) to recoat and enhance the existing coating. Other alternatives are to use a quality, high-grade 100% acrylic exterior grade paint. Before recoating, appropriate repairs should be made and the surface should be cleaned to remove any surface contamination. Whom do I contact if I need repairs? EIFS manufacturers provide a distributor locator on their website to locate the distributor nearest you. The distributor can assist you in locating appropriate qualified contractors. The Association of Wall and Ceiling Industry (AWCI) also provides on its website a national database of contractors who have gone through and passed the EIFS Doing it Right course. How long should EIFS last? If properly maintained, the cladding will last the life of the building. Initial EIFS walls were installed in the late 1960 s and most are still in service as of this writing (2014). Do insurance companies cover EIFS projects? The EIFS Industry Members Association (EIMA) compiled a list of insurance companies that offer coverage to EIFS projects. In addition, EIMA is working with some other companies that do not currently offer insurance for EIFS projects, on expanding their coverage to be more inclusive for these projects. A listing of these companies can be found at a page sponsored by VELA Insurance Services, out of Chicago, Ill. EIFS Industry Members Association (EIMA) 513 West Broad Street, Suite 210 Falls Church, VA 22046