【正文】 products with low life cycle costs. As more mainstream window and door manufacturers introduce fiberglass lines for new construction and replacement situations, products have bee available in a full range of energyefficient options including lowE argonfilled insulating glass units and in a variety of styles from casement to single and doublehung to plex custom profiles. This article will discuss next generation offerings in fiberglass windows and provide a parative analysis of fiberglass and other framing materials. Also covered will be code and design considerations in specifying an appropriate fiberglass window FIBERGLASS WINDOW OPTIONS According to , a non profit website whose sole mission is to encourage the creation of wellbuilt buildings made with sustainable materials, using fiberglass for a window frame material is, in some cases, preferable to other window frame materials like wood, vinyl, or metal”A relatively young product, fiberglass window frames are available in several versions Chief among them are the allfiberglass frame that bines a traditional woodframe profile with the strength, stability and low maintenance characteristics of fiberglass. These windows resemble traditional painted wood windows with factory applied exterior colors. Quite recently, manufacturers have also introduced a line of windows in which the fiberglass production process enables plex profiles required for the look of painted wood windows on the exterior, bined with a natural wood interior. Better options in this category feature furnituregrade, clear, verticalgrain Douglas fir, mahogany or other species on the interior unmarred by nail or staple holes, a powdercoated exterior finish and builtin systems to increase both energy efficiency and window longevity. FIBERGLASS: WHAT IS IT AND HOW IS IT MADE? Fiberglass is a posite structural material that consists of fiber reinforcements, typically glass, that are bound together in a resin matrix. Unlike mon fiberglass used in pools, boats, and storage tanks, fiberglass frames are produced via pultrusion, a process in which glass rovings and mats are pulled at tremendous force through a resin bath and a series of dies where the resin sets to the desired shape and the materials bine and catalyze to provide high tensile and torsional strength. These dimensionally stable fiberglass lineals are then assembled into window frames, which can be filled with foam insulation and glazed with highperformance lowE insulating glass for higher performance. Fiberglass window frames are produced similarly to vinyl, however where fiberglass is pultruded, or pulled, vinyl is extruded, or pushed, through a form tocreate a similar shape. ATTRIBUTES OF FRAMING MATERIALS The window frame which makes up some 20 percent of the total window area,is an important factor in window39。 Requires maintenance Strength. Fiberglass provides the strongest window material, with experts maintaining it is some threetimes stronger than aluminum and nine times strongerthan vinyl. According to the American ArchitecturalManufacturers Association (AAMA), fiberglass profiles have roughly the same strength as steel (based on tensile strength). Its strength enables fiberglass to be fabricated in large sizes, acmodating large expanses of glass without requiring added support or reinforcement, making large picture windows possible and energyefficient High strengthtoweight ratio. lts light weight gives fiberglass a high strengthtoweight ratio, adding to its suitability for large, plex profilesbenefits in both maximizing daylighting and enhancing historical accuracy m restoration projects. Aluminum Because of their rigidity, durability and narrow frames, aluminum windows can be configured into a wide variety of binations that maximize views. Aluminum windows are lowmaintenance options