随着对节能的进一步强调，没有一栋建筑的对应物比窗户更具争议性。许多人指责窗户浪费能源，他们持短视的观点，认为在住宅中减少窗户面积将减少能源消耗。在评价窗的能量性能时，人们简单地考虑产品的U值，并将其与绝缘壁的U值进行比较。通过这样的比较，可以得出结论，即使是一个良好的隔热双层玻璃窗产品也比隔热良好的墙传导更多的能量。但窗户不是墙——它的目的不是像墙一样，成为外部环境的整体屏障，而是作为内部和外部环境之间的自然价值。 窗户是照明、通风、供暖和制冷的来源，为建筑物的居住者提供与外部环境的必要互动。如果在设计一栋建筑时不考虑这些因素，那么一个相当令人惊讶的解决方案就是取消所有窗户，而采用高度隔热的墙壁。然而，大量研究已经证明，减少建筑物中的窗户并没有必要减少建筑物的能耗。正确设计、定位和管理窗户实际上可以降低照明、供暖和空调成本。本质上，需要做的是把窗户看作是整个系统的一部分，而不是作为建筑物的独立部件。在以这种方式分析窗户并评估其对建筑节能性能的总体贡献时，有可能设计出一种不仅节能而且能提供传统上被认为是窗户使用的理想特征的建筑和人文互动特征的结构。 正确使用窗户的建筑设计和节约能源的窗户管理是需要解决的极其重要的课题；它们本身就是专门的主题，本文将不讨论。本文将详细介绍窗户性能的基本概念和窗户产品的热测试。引文:宾夕法尼亚州费城ASHRAE学报第85卷第1部分研讨会

With the added emphasis on energy conservation, no corrponent of a building has been thesubject of more controversy than the window. Windows are accused of being energy wastersby many people who take the short-sighted viewpoint that reducing the window areas in abuilding will reduce energy consumption. In evaluating the energy performance of a windowmany people simply consider the U-value of the product and compare it to the U-value of awell-insulated wall. With such a comparison it can be concluded that even a good insulateddouble glazed window product will conduct considerably more energy than a well insulatedwall. But a window is not a wall - it's purpose is not to act as a wall does and be a totalbarrier to the outside environment, but rather to function as a natural value between theinternal and external environment. Windows are a source of illumination, ventilation, heating,cooling and provide the occupants of a building with needed interaction with the outsideenvironment. If these factors are not taken into account when designing a building, the quiteobvious solution would be the elimination of all windows in favor of highly insulated walls.However, numerous studies have proven that reducing windows in buildings does not necessarilyreduce the energy consumption of the building. Properly designed, located and managed windowscan actually reduce lighting, heating and air-conditioning costs. In essence, what needs tobe done is to consider windows as part of a total system rather than as an independent componentof the building. In analyzing windows in this manner and evaluating their totalcontribution to the energy performance of a building, it is possible to design a structurethat is not only energy efficient but also one that provides the architectural and humaninteraction characteristics traditionally accepted as desirable features of window usage.The design of buildings to make proper use of windows and the management of windows tosave energy are extremely significant subjects that need to be addressed; they are specializedtopics in themselves and will not be discussed in this paper. The paper will deal specificallywith the very basic concept of window performance and the thermal testing of window products.