供暖、通风和空调系统的设计在很大程度上取决于对热负荷和冷负荷的实际估计，以保持住宅结构的舒适性，同时有效地运行。无论建筑类型、位置或气候条件如何，都是如此。在大多数环境控制应用中，系统大部分时间在部分负载下运行。因此，加热和冷却设备的尺寸必须适当，以尽量降低部分负荷运行的低效率。设备尺寸过大也会导致湿度控制问题。设备尺寸过小会产生明显的后果；然而，这似乎并不是当前负荷计算程序的缺陷。本文描述了一个研究计划，其中对所有住宅负荷计算程序和数据进行了调查，这些程序和数据可通过搜索文献、个人联系和其他方法确定，并记录了材料。 同时，对商业结构的类似程序进行了筛选，以备日后在编制荷载计算方法时使用。根据文献调查，制定了一项计划，以开发一种考虑到所有类型住宅结构需求的方法。注意确保所有程序在已发表的文献中有良好的基础，与当前的商业程序一致，最重要的是，产生一致可靠的结果。

The design of a heating, ventilating and air conditioning system to maintain comfort in a residential structure while operating efficiently is highly dependent on realistic estimates of the heating and cooling loads. This is true regardless of building type, location, or climatic conditions. With most environmental control applications, the system operates at part load most of the time. Therefore, it is essential that the heating and cooling equipment be properly sized to minimize the low efficiency of partial load operation. Equipment oversizing also leads to problems of humidity control. Equipment undersizing has obvious consequences; however, this does not seem to be a deficiency of present load calculation procedures.A program of research is described herein where a survey of all the residential load calculation procedures and data that could be identified through a search of the literature, personal contacts and other methods was made and the material documented. At the same time similar procedures for commercial structures were screened for later use in preparation of a load calculation method. From the literature survey a plan was formulated to develop a method which takes into account the needs of all types of residential structures. Care was taken to ensure that all procedures have a sound basis in the published literature, are consistent with current commercial procedures, and, most of all, yield consistent reliable results.