UNDERSTANDING E.I.F.S.

Under The Guidance of

Dr A. Deiveegan

Assistant Professor

Department of Civil and Structural Engineering

Annamalai University

Presented By

Shashank Srivastava Department of Civil Engineering Annamalai University

INTRODUCTION• According to the definitions of the

International Building Code and ASTM International, an Exterior Insulation and Finish System (EIFS) is a non load 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’s are among the most cost-effective building technologies for improving the insulating value of walls and the energy efficiency of buildings.

HISTORY OF E.I.F.S.• EIFS started to be used in North America in the 1960s, and became

very popular in the mid- 1970s due to the oil embargo and the resultant surge in interest in high energy efficiency wall systems (such as EIFS provides). The use of EIFS over stud-and-sheathing framing (instead of over solid walls) is a technique used primarily in North America. EIFS is now used all over North America, and also in many other areas around the world, especially in Europe and the Pacific Rim.

NECESSITY OF E.I.F.S.• When installed properly, EIFS makes buildings more energy efficient.

Initially, it can cost more, but EIFS pays for itself over time. According to Oak Ridge National Laboratory, structures with EIFS can save between 20 percent and 30 percent on energy bills.

• Expanded polystyrene (EPS) is part of the system, and it can be cut or molded to create many shapes like arches, columns, window details and sculptures. It can also be used to create elaborate architectural designs, ornate facades or soffits.

EIFS today are one of the most tested and well researched claddings in the construction industry. Research, conducted by the Oak Ridge National Laboratory and supported by the Department of Energy, has validated that EIFS are the "best performing cladding" in relation to thermal and moisture control when compared to brick, stucco, and cementitious fibreboard siding.

In addition EIFS is in full compliance with modern building codes which emphasize energy conservation through the use of CI (continuous insulation) and a continuous air barrier. Both these components are built into today's EIFS products to provide maximum energy savings, reduced environmental impact over the life of the structure, and improved IAQ, Indoor Air Quality. Along with these functional advantages come virtually unlimited colour, texture, and decorative choices to enhance curb appeal and enjoyment of almost any home or structure.

 

COMPONENTS OF E.I.F.S.• Substrate: This layer is placed over stud walls, concrete walls, or masonry walls. Oriented strand

board, plywood, gypsum board, cement board, Dense Glass Gold, and poly iso board have all been used.

• Adhesive or Mechanical Fasteners: Mechanical fasteners pass through the insulation board to the substrate. Adhesive fasteners are applied between the insulation board and substrate. The two types of fasteners are typically used together.

• Exterior Insulation: Molded expanded polystyrene boards or extruded expanded polystyrene boards.

• Fiber Reinforcing Mesh: Fabric or fiber reinforced mesh is commonly found within the base coat.

• Base Coat: A layer that consists of fiber-reinforced or fabric-reinforced mesh and a cementitious compound. Base coat properties and quality finishes influence the durability of an EIFS more than any other component, making it the most important of all components.

• Finish Coat: Commonly an acrylic "stucco type" or aggregate based system.

PROCESS OF APPLYING E.I.F.S.• Without impacting life indoors, EIFS can be installed on new buildings or old

structures that need a facelift or structural improvements. Plastering contractors can install it at the construction site by hand or the system can be delivered on site as factory-made panels that are ready to attach to a building via crane.

• EIFS is typically attached to the outside face of exterior walls with an adhesive (cementitious or acrylic based) or mechanical fasteners. Adhesives are commonly used to attach EIFS to gypsum board, cement board, or concrete substrates. EIFS is attached with mechanical fasteners (specially designed for this application) when installed over sheet-good weather barriers such as are commonly used over wood sheathings. The supporting wall surface should be continuous (not "open framing") and flat.

ADVANTAGES OF E.I.F.S.

• E.I.F.S. provides many advantages that other exterior finishes and sidings do not.  Chief among these are superior energy efficiency and great design flexibility.  As a matter of fact, studies have shown that EIFS can reduce the air infiltration in a wall by as much as 55%, when compared to standard brick or wood construction.

• It can be cut or molded to create many shapes like arches, columns, window details and sculptures. It can also be used to create elaborate architectural designs, ornate facades or soffits.

Just as EIFS is architecturally versatile, it's also flexible when it comes to installation. Often, foam board is applied with adhesive that won't work in extremely low or high temperatures. By completing the EIFS in panels indoors in a warehouse, the adhesive can dry. Then, the system can be installed in extremely hot or cold places that otherwise couldn't accommodate constructionEIFS is in full compliance with modern building codes which emphasize energy conservation through the use of CI (continuous insulation) and a continuous air barrier. Both these components are built into today's EIFS products to provide maximum energy savings, reduced environmental impact over the life of the structure, and improved IAQ, Indoor Air Quality. Along with these functional advantages come virtually unlimited colour, texture, and decorative choices to enhance curb appeal and enjoyment of almost any home or structure.

DISADVANTAGES OF E.I.F.S.• Exterior Insulation and Finish Systems (EIFS) installation can be technically

challenging, sometimes making the cons overshadow the pluses. According to C-Risk, Inc., a risk-management consulting firm, installation problems are due in part to manufacturers' systems all being different: Different systems require different installation techniques.

• Inexperienced workers plus fast-tracked construction can equal compromised EIFS products that leak - one of the many things that can go wrong during installation.

It's normal for exterior walls to have moisture within them, and most are designed to let water escape or dry. However, once water gets behind the EIFS, it has a difficult time getting out. If EIFS fails its waterproof claim and leaks, it can be extremely difficult to identify who is responsible since there are a number of people who contribute to the integrity of the system: homeowner, manufacturer, supplier, builder, designer, installer, electrician, roofer.

The EIFS external barrier system depends upon a perfect external water barrier to keep water out of wall cavities. Since the outer shell is the only barrier against water intrusion, it must form a “perfect” barrier at “all times.”  When there are so many entry points for water intrusion in the exterior shell of a house, this is an unrealistic expectation.  

CONCLUSION• From the above discussion, it is quite clear that E.I.F.S. is a

type of modern day cladding systems which provides perfect insulation and decreases the energy losses, while on the other hand, requires extra capital in initial stage and is not preferable in absence of Skilled labour. However, when applied effectively, it can be an excellent finishing material with many long lasting effects.

REFERNCES• Introduction & History: Wikipedia [

www.en.wikipedia.org/wiki/Exterior_insulation_finishing_system]

• Necessity: Oak Ridge National Laboratory[Bethel Valley Rd, Oak Ridge, United States]• Components: Kevin C. Day[Building Engineering Division, Morrison Hershfield Limited]• Process of Applying EIFS: STO International[Ehrenbachstraße 1,79780 Stühlingen

Germany]

• Advantages & Disadvantages: Technical Services Information Bureau

THANK YOU