Scalable method to assess ventilation rates in dwellings

了解现有建筑的空气交换率越来越重要，特别是在改造的背景下。提高住宅能源效率的改造干预措施很可能导致通过渗透减少空气交换，重要的是要确保这不会对建筑物的整体背景通风率产生负面影响。有许多已确立的测量和表征建筑物内空气交换率的技术。尽管如此，目前关于英国现有住宅通风率的数据很少。部分原因是由于大规模部署现有技术（如示踪气体）的复杂性和成本。然而，随着智能恒温器的日益普及，未来有可能为大量住宅提供温度和湿度数据。该项目旨在探索如何使用这些数据来估计通风率。只要记录了内部和外部的湿热条件，就可以推导出产生的蒸气压过剩，即水分含量高于外部水平。由于过量蒸汽压实际上是内部水分生成和通风效率的函数，理论上可以使用过量蒸汽压来估计通风量。

TKnowledge of air exchange rates in existing buildings is increasingly important, especially in the context of retrofit. Retrofit interventions to improve the energy efficiency of a dwelling will most likely lead to a reduction in air exchange through infiltration, and it is important to ensure that this does not negatively impact the overall background ventilation rate in the building.There are many established techniques for measuring and characterising air exchange rates in buildings. Despite this, there is currently very little data available regarding ventilation rates of existing dwellings in the UK. This is partly due to the complexity and cost of deploying established techniques, e.g. tracer gases, at scale.However, through the increasing uptake of smart thermostats it is likely that temperature and humidity data will be available for large numbers of dwellings in the future. This project aims to explore how this data can be used to estimate ventilation rate. Provided both internal and external hygrothermal conditions are recorded, the resulting vapour pressure excess, i.e. moisture content rise above external levels, can be derived. Since vapour pressure excess is effectively a function of internal moisture generation and ventilation effectiveness, estimates of ventilation rate can theoretically be made using vapour pressure excess.