外墙外保温系统中英文.docx

1、外墙外保温系统中英文Exterior Insulation Finishing SystemExterior 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.Contents1 Terminology 2 How E

2、IFS is 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 TerminologyAlthough often called synthetic stucco, EIFS is not stucco. Traditional stucco, otherwise known as Portland Cement Plaster,

3、 is a 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 th

4、at use 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 F

5、inish 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 prope

6、rly, 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

7、a water 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 no

8、t include 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

9、 EIFS 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 showin

10、g typical 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 ty

11、pical home consumer.How EIFS is installedEIFS 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

12、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.Composition and types of EIFSEIFS consists of a number of layers

13、 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. Mo

14、st EIFS use a type of insulation called Expanded Polystyrene, also known as EPS. EPS is 1lb. 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 accent

15、s - 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 mad

16、e 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 called t

17、he 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, em

18、bedded 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 (generally D

19、ensGlas 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 space

20、 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. The p

21、urpose 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 (ceme

22、ntless). 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 Portland

23、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.History

24、 of EIFSEIFS 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 s

25、ystems (such as EIFS provides). The use of EIFS over stud-and-sheathing framing (instead of over solid walls) is a North American technique. EIFS is now used all over North America, and also in many other areas around the world, especially in Europe and the Pacific Rim.In North America, EIFS was ini

26、tially used almost exclusively on commercial buildings. As the market grew, prices dropped to the point where its use became widespread on normal single family homes.In the late 1980s problems started developing due to water leakage in EIFS-clad homes. This created a national controversy and numerou

27、s lawsuits. While not inherently more prone to water penetration than other exterior finishes, critics argue that barrier-type EIFS systems (non-water-managed systems) do not allow water that may penetrate the building envelope to escape. The EIFS industry has consistently maintained that the EIFS i

28、tself was not leaking, but rather poor craftsmanship and bad architectural detailing at the perimeter of the EIFS was what was causing the problems. The building codes reacted by mandating EIFS with Drainage on wood frame building and additional on-site inspection. Most homeowner insurance policies

29、cover EIFS and EIFS-like systems.Insurance companies like FM Global may not provide fire insurance coverage to clients who install EIFS exterior building systems, due to the lack of adequate fire-resistance inherent in the materials. Also, some facility owners have found that EIFS systems that are i

30、nstalled at lower building levels are subject to vandalism as the material is soft and can be chipped or carved resulting in significant damage.Legal issuesEIFS systems have been the subject of several lawsuits, mostly related to the installation process and failure of the system causing moisture bu

31、ildups and subsequent mold growth. The most notable case concerned the former San Martin, California courthouse. This case was settled for 12 million dollars. The basic underlying problem behind EIFS litigation was that EIFS was marketed as a cost-effective replacement for stucco. Stucco is expensiv

32、e to install because it cracks over time. Stucco must be carefully applied by skilled craftsmen so that the cracks which will inevitably develop are subtle and not obvious. General contractors switched to EIFS because it was supposed to be easy to install with unskilled or semi-skilled labor and would not crack like traditional stucco. Although EIFS if properly installed according to the manufacturers directions should not have water intrusion problems, many GCs cut corners by using unqualified labor. In turn, thousands of EIFS installations were noncompliant and suffered severe water