1、Exterior Insulation Finishing System Exterior Insulation and Finishing System (EIFS) is a type of building exterior wall cladding system that provides exterior walls with an insulated finished surface and waterproofing in an integrated composite material system. Contents 1 Terminology 2 How EIFS is
2、installed 3 Composition and types of EIFS 4 History of EIFS 5 Legal issues 6 Marketing of EIFS and The EIFS Industry 7 EIFS Architectural Details 8 References Terminology Although often called synthetic stucco, EIFS is not stucco. Traditional stucco, otherwise known as Portland Cement Plaster, is a
3、centuries-old non-insulating material. Stucco consists of sand, Portland Cement, and water, and is a hard, dense, thick, non-insulating material. EIFS is a lightweight synthetic wall cladding that includes foam plastic insulation and thin synthetic coatings. There are also specialty stuccos that use
4、 synthetic materials but no insulation, and these are also not EIFS either. A common example is what is called one-coat stucco, which is a thick, synthetic stucco applied in a single layer (traditional stucco is applied in 3 layers). There is also an EIFS-like product called a Direct-Applied Finish
5、System (or DAFS), which is essentially an EIFS but without the insulation, and has quite different characteristics. EIFS are proprietary systems of a particular EIFS producer and consist of specific components. EIFS are not generic products made from common separate materials. To function properly,
6、EIFS needs to be architecturally designed and installed as a system. There are a number of versions of EIFS. The most basic and common EIFS is called a barrier EIFS (also known as a traditional or conventional EIFS). Another type is called an EIFS with Drainage, which is a barrier EIFS to which a wa
7、ter drainage capability has been added. A basic EIFS includes only the insulation and EIFS materials (coatings, adhesives, etc.). Other types of EIFS may also include plastic edge trim, water-resistive barriers, a drainage cavity, and other accessories. The technical definition of an EIFS does not i
8、nclude wall framing, sheathing, flashings, caulking, water barriers, windows, doors, and other wall components. However, as of recently, architects have begun specifying flashings, sealants, and wiring fasteners (such as Viperstrap) as being a part of the EIFS scope of work, essentially requiring EI
9、FS contractors to carry out that work as well. The technical national consensus standard for the definition of an EIFS, as published by ASTM International organization, does not include flashing or sealants as part of the EIFS. Many of the EIFS manufacturers have their own standard details showing t
10、ypical building conditions for window and door flashings, control joints, inside/outside corners, penetrations, and joints at dissimilar materials which should be followed for that manufacturers warranty. Most EIFS products are intended for use by qualified professional contractors and not the typic
11、al home consumer. How EIFS is installed 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 m
12、echanical 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. Composition and types of EIFS EIFS consists of a number of layer
13、s that are installed in the following order. The most basic EIFS (a barrier EIFS) consists of 3 layers: A layer of foam plastic insulation (also called simply foam) that comes in the form of sheets . If an adhesive is used to attach the insulation, the adhesive is applied to the foam with a trowel.
14、Most EIFS use a type of insulation called Expanded Polystyrene, also known as EPS. EPS is 1 lb. density Expanded Polystyrene, similar to the white foam that coffee cups are made of. The usual range of thickness for EIFS insulation is 3/4, although thicker pieces are sometimes used for decoration acc
15、ents - called foam shapes. A reinforced layer that is applied onto the face of the insulation with a trowel, consisting of a fiberglass reinforcing mesh ( or mesh) embedded in a cementitous adhesive. The mesh has an open weave, somewhat like window screening but with opening about 1/4 square. It is
16、made of fiberglass and can be cut with a utility knife. The mesh is available in various weights, the heaviness determines the impact strength of the surface (resistance to damage by being hit). The standard weight is 4oz, the high-impact mesh weight goes up to 15 or 20oz. This 2-part layer is calle
17、d the Base Coat. A final topcoat,or finish, which is a colored, textured paint-like material that is applied with a trowel or, very rarely, by spraying. A wide range of colors and textures are available as well as custom colors. Available textures include smooth surfaces, rough stucco-like textures,
18、 embedded stone chips, multi-color (granite-like mixtures,) and even brick-like treatments. This layer is called the finish. It is acquired by floating. If an EIFS with Drainage, or water-managed EIFS is installed, a water resistive barrier (aka a WRB) is first installed over the substrate (generall
19、y DensGlas Gold, exterior-grade gypsum sheathing, OSB or plywood). The moisture barrier is applied to the entire wall surface with a mesh tape over joints and a liquid-applied membrane or a protective wrap like Tyvek or felt paper. Then a drainage cavity is created (usually by adding some sort of sp
20、ace between the foam and the WRB). Then the other 3 layers, described above, are added. This type of EIFS is required by many building codes areas on wood frame construction, and is intended to provide a path for incidental water that may get behind the EIFS with a safe route back to the outside. Th
21、e purpose is to preclude water from damaging the supporting wall. Adhesives and Finishes are water-based, and thus must be installed at temperatures well above freezing. Two types of Adhesives are used with EIFS: those that contain Portland Cement (cementitious), or do not have any Portland Cement (
22、cementless). Adhesives that contain Portland Cement harden by the chemical reaction of the cement with water. Adhesives and Finishes that are cementless harden by the evaporation of water - like house paint. Adhesives come in two forms. The most common is in a plastic pail as a paste, to which Portl
23、and Cement is added. Adhesives are also available as dry powders in sacks, to which water is added. Finishes come in a plastic pail, ready to use, like paint. EIFS insulation comes in individual pieces, usually 2 x 4, in large bags. The pieces are trimmed to fit the wall at the construction site. Hi
24、story of EIFS EIFS was developed in Europe after World War II and was initially used to retrofit solid masonry walls. 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
