Investigation of natural aeration in home offices during the heating season – case study

Abstract

Buildings are more and more airtight in order to meet the energy performance requirements of national regulations. To provide appropriate air quality for occupants’ energy conscious ventilation systems are installed. However, in residential buildings natural ventilation methods are widely used. Because of the COVID-19 pandemic lots of people working initially in offices suddenly started to perform their activities at home, so they worked in so called home-office regime. Thus, rooms without mechanical ventilation were transformed from one day to other in offices. However, appropriate indoor air quality has to be provided since the human performance strongly depends by the CO2 concentration in the air. The aim of this research was to analyse and compare different natural aeration methods which can be adopted in this cases from energy point of view. A residential building built in 2014 was taken as an example, having gas filled triple glazed windows Class 3. The air change rates were determined at different temperatures having the window fully opened or tilted. Measurements were performed with and without occupants in the room in order to validate the results obtained from CO2 balance equation. The energy demand for heating up the fresh air was analysed. It was shown that up to 18% energy saving may be obtained choosing properly the aeration strategy. The paper draws the attention of stakeholders on the fact that changing the function of a room can lead to significant increase of energy consumption, which can be mitigated controlling properly the aeration process.