ventilation

Worldwide the food system is responsible for 33% of GHG emissions. It is estimated that by 2050, total food production should be 70% more than current food production levels.   In the UK, food chain is responsible for around 18% of final energy use and 20% of GHG emissions. Estimates indicate that energy savings of the order of 50% are achievable in food chains by appropriate technology changes in food production, processing, packaging, transportation, and consumption.  

The exposure of children to indoor air pollutants in school classrooms might cause them adverse health effects. In order to confront this issue, the in-depth study and evaluation of the indoor air quality in classrooms is necessary. The aims of this study are to characterize the environmental factors that affect indoor air quality.

Air quality in the office room areas, as well as their energy demands for heating and cooling are directly depended on the ventilation levels in those rooms. Specifically, high internal air quality requires high levels of ventilation and therefore high energy demands. On the other hand, high energy savings can be accomplished by full building impermeability, which means low to none ventilation and at the same time low air quality.

Airtightness and controlled ventilation are important factors affecting energy use and indoor air quality. Airtightness tests were carried out on nine naturally ventilated social houses in Ireland. Subsequently, four of the houses were retested following energy efficient upgrading. The upgrading largely consisted of improving fabric insulation and where required the mandatory installation of passive wall vents. Interviews were conducted with the occupants to gain their perspectives of airtightness and ventilation in their homes.

Ventilation’s historical goal has been to assure sufficient air change rates in buildings from a hygienic point of view. Regarding its potential impact on energy consumption, ventilation is being reconsidered. An important challenge for low energy buildings lies in the need to master airflows through the building envelope.

Reducing adventitious infiltration in order to save energy is important and is highlighted by the building standards of many countries.  This operational infiltration is often inferred via the measurement of the air leakage rate at a pressure differential of 50 Pascals.  Some building codes, such as the UK’s Standard Assessment Procedure, assume a simple relationship between the air leakage rate and mean infiltration rate during the heating season, the so-called leakage-infiltration ratio, which is scaled to account for the physical and environmental properties of a dwelling.  The scaling d

From 2006 till 2012, the 2005 energy performance (EP) regulation (RT 2005) did not entail any obligation to justify the envelope airtightness level. As a consequence, asking for the certification of airtightness quality management approaches was a voluntary request from constructors. Thus, they might be allowed to take into account a better-than-default value into the thermal calculation. Since 2012, French 2012 EP regulation (RT 2012) requires building airtightness level to be justified, with two ways of justification.

The work evaluates the applicability of façade-integrated ventilation systems in a Nordic climate. For this purpose the state of the art of façade-integrated ventilation (FIV) and demands for ventilation system in Norway and criteria for an comprehensive evaluation are identified. In this framework agreements between national requirements and system-specific performance are assessed. The evaluation investigates indoor environment and comfort with focus on aspects of indoor air quality.

Diffuse ceiling ventilation is a novel air distribution device that combines the suspended acoustic ceiling with ventilation supply. A diffuse ceiling distributes the supply air above the acoustic tiles and has proven performance in laboratory experiments. To study the performance in real conditions a classroom was retrofitted with mechanical ventilation and a diffuse ceiling. The employed ceiling comprises active panels penetrable to air and impenetrable passive panels.

This paper reports on the construction, experimental set up and infiltration characteristics of a purpose built full-scale experimental house. The building has been designed as an experimental platform for measuring the moisture removal effectiveness of active and passive ventilation systems with indoor and outdoor climate conditions seen in New Zealand.