Airbase publication

The materials that compose the built environment have a key role in the resulting energy demand since their thermal properties affect the heat transfer processes. The use of cool materials aims at increasing the albedo of the urban surfaces and decreasing the heat absorbed by them. Cool materials can decrease roof temperatures, reduce energy needs for cooling and improve indoor comfort for spaces that are not air conditioned.

Ventilation in dwellings is likely to be impacted by configurations of windows and internal doors, but there is little empirical research investigating this in occupied homes. Closure of internal doors will affect noise, light, heat flow and how air moves into and through a building, as well as the volume of air in which pollutants are diluted.

Due to age-related physiological changes, older people are more vulnerable than young people to heat or cold conditions. Predicting older people's thermal sensations is essential for controlling the built environment and avoiding extreme heat/cold injuries. Previous studies mainly focused on predicting the thermal sensation of young people, and the data-driven methods are often not constrained by physiological responses. This study proposes a new integrated model to combine the two-node physiological model and the data-driven method random forest classifier.

The fan pressurization method is a common practice in many countries for measuring the air leakage of houses. The test results are sensitive to uncertainties in the measured pressures and airflows. In particular, changing wind conditions during a test result in some pressure stations having more or less uncertainty than others. Usually, it is necessary to fit the measured data to the power-law equation.

France is committed to minimizing its greenhouse gas emissions by focusing on the most energy-consuming sector, the residential and tertiary building sector. The renovation of existing buildings and the construction of energy efficient ones are therefore proposed as a possible solution. However, the concept of efficiency is ambiguous and difficult to measure and compare without common parameters and indicators. Indeed, a performance indicator is a decision support tool that describe the specific situation of something based on certain parameters.

Infiltration of unconditioned air through access openings and entrance doors with high recurrence can cause detrimental impacts to the energy performance, air quality and thermal comfort of buildings. Air curtains are of strategic importance to attenuate these negative impacts. In addition, air curtains are relevant in specialized HVAC applications for which the impediment of infiltration is also essential (e.g., reduction of smoke propagation in fire events, decrease of contamination hazard in clean rooms, preservation of refrigeration properties in cold rooms).

In the UK, people spend over 90% of a day indoors. On weekdays, when outdoor air pollution concentrations peak in the morning and in the late afternoon, people are usually either in non-domestic premises or on their way to/from non-domestic premises. Therefore, establishing the distributions of indoor air pollutant concentrations in non-domestic environments is essential to model human exposure to hazardous air pollution, especially for vulnerable populations, such as schoolchildren or patients in hospitals.

Ventilation systems assume that the outdoor air quality is better than the indoor air quality at al times as they use outdoor air to dilute pollutants emitted by humans, activities, the building itself and other objects. However, the outdoor air quality is not always as clean as assumed. Traffic, industry and agriculture can pollute the outdoor air making the outdoor air also a source of certain unhealthy pollutants indoors. This challenges the before stated assumption as in this case less ventilation would lower this source of pollution to the indoor environment.

Humidity-based DCV systems have been widely used in France for 35 years and are considered as a reference system, including for low-energy residential buildings. The on-going Performance 2 project delivers the preliminary results of a thirteen-year monitoring in thirty social housing apartments.

In building energy renovation, the notion of payback time of the investments is often presented as the only goal. However, the potential benefits in terms of health are also valuable despite being not consciously perceived by the occupant and may need to be monitored to be assessed. Laboratory-grade devices or protocols are generally burdensome and expensive, and the growing popularity of low-cost devices may contribute to the perception of health benefits at a larger scale.