Abstract Buildings are responsible for 40% of the global energy usage to which infiltration-caused heat losses are responsible for 30%. Air infiltration is the unintended flow of air through leakage paths and fundamentally determined by the airtightness of a building. In the United Kingdom, building airtightness is conventionally measured through a blower door test and used to predict air infiltration in conjunction with the divided-by-20 rule, which is a rule of thumb that has been adopted by SAP (Standard Assessment Procedure: a UK government's recommended method system for measuring the energy rating of residential dwellings) for the estimation of the infiltration-caused heat losses for dwellings. This paper assesses the representativeness of this rule of thumb by carrying out blower door and tracer gas tests in twenty one dwellings located in the East Midlands Region of the United Kingdom. Results showed that a divide-by-37 rule would be more representative. It was also seen that the air infiltration rate is overestimated by SAP when modifying factors are added. The errors are as high as 500% in some cases. The most affected dwellings were the tighter ones. A revision of the usage of the divide-by-20 rule and the modifying factors is advised.

中文翻译：

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用除以 20 规则估计英国家庭的渗透率及其与现场测量的比较

摘要 建筑物占全球能源使用量的 40%，其中渗透引起的热损失占 30%。空气渗透是空气通过泄漏路径的意外流动，从根本上取决于建筑物的气密性。在英国，建筑物气密性通常通过鼓风机门测试来测量，并结合除以 20 规则来预测空气渗透，该规则是 SAP 采用的经验法则（标准评估程序：a英国政府推荐的测量住宅能源等级的方法系统），用于估算住宅渗透引起的热损失。本文通过在位于英国东米德兰兹地区的 21 个住宅中进行鼓风机门和示踪气体测试来评估该经验法则的代表性。结果表明，除以 37 的规则更具代表性。还可以看出，当添加修正因子时，SAP 高估了空气渗透率。在某些情况下，错误率高达 500%。受影响最严重的住宅是较紧凑的住宅。建议修改除以 20 规则和修改因子的用法。受影响最严重的住宅是较紧凑的住宅。建议修改除以 20 规则的用法和修改因子。受影响最严重的住宅是较紧凑的住宅。建议修改除以 20 规则的用法和修改因子。