In most of standards and design codes, the selection of parameters or size of the openings/windows plays an important role. It influences the thermal and daylight distribution in the room, which provide thermal and visual comfort, define energy efficiency criteria. Offering a rational window size, which is largely known as the Window to Floor ratio (WFR) will help builders and architects in the design process. Mostly, this ratio can be approximately determined by the rule of thumb. In the Russian Standard documents, daylighting assessment criteria for side lit space of the public and office buildings are represented by the minimum Daylight Factor (DF_M). The Window to Floor Ratio could be calculated based on this value. In recent studies, to provide at least 50% of floor area in occupied spaces that have a target illuminance for 50% of daylight time, the daylighting assessment has been based on the target Daylight Factor (DF_T), which is defined by the median value and the new target minimum Daylight Factor (DF_TM). This means the WFR should be recalibrated to satisfy the DF_T and DF_TM instead of DF_M. Focusing on this aim, it is necessary to find out the relationship between the DF_T and the DF_M in a space. In other words, the uniform of Daylight Factor standing on the rule of daylight distribution in spaces should be analysed using the method of experiments and modelling. The results show that in the typical spaces, the DF_M^—which is used to calculate WFR could be accepted by the value of \(\frac{{1}}{{3}}\) of the DF_T, the WFR is not only proportional to the DF_T but also depends on the character of daylit space, which described by the ratio of the room depth to the window height in a proportional relation.

在大多数标准和设计规范中，开口/窗户的参数或尺寸的选择起着重要作用。它影响房间内的热量和日光分布，提供热量和视觉舒适度，定义能源效率标准。提供合理的窗户尺寸，这在很大程度上被称为窗地板比 (WFR)，将在设计过程中帮助建筑商和建筑师。大多数情况下，这个比率可以通过经验法则大致确定。在俄罗斯标准文件中，公共和办公建筑侧光空间的采光评估标准由最小日光系数（DF _M）。可以根据该值计算窗地板比。在最近的研究中，为了在具有 50% 日光时间的目标照度的占用空间中提供至少 50% 的建筑面积，日光评估基于目标日光系数 (DF _T )，由中位数定义值和新的目标最小日光系数 (DF _TM )。这意味着应该重新校准 WFR 以满足 DF _T和 DF _TM而不是 DF _M。围绕这个目标，有必要找出DF _T和DF _M之间的关系在一个空间里。换言之，要根据空间日光分布规律，对日光因子的均匀性进行分析，采用实验和建模的方法。结果表明，在典型空间中，用于计算 WFR的 DF _M ^—可以被DF _T的\(\frac{{{1}}{{3}}\)的值所接受，WFR 为不仅与 DF _T成正比，而且还取决于采光空间的特征，用房间深度与窗户高度的比例成比例关系来描述。