English

The airtightness of office and educational buildings influences energy use and thermal comfort. A leaky building is likely to have a high use of energy and thermal discomfort. The knowledge of real airtightness levels of entire buildings and their impact on the energy use is very low, except for a study carried out in the USA. Therefore two different methods of airtightness testing were applied to six entire Swedish office and educational buildings built since 2000. The first method involves using the ventilation system of the building and the second one to use a number of blower doors.

The monitoring of a demand controlled heat recovery ventilation system with ground heat exchange in a zero-energy building in Groenlo, The Netherlands, revealed interesting practical insights.

In Spain, the residential sector is the third principal source of energy consumption; many of these dwellings are obsolete and do not have optimal conditions of comfort. For this reason, their energy retrofitting means an enormous step towards the energy efficiency. Under the general intervention strategies, the study and analysis of the air-tightness of the building envelope (as measured by the degree of infiltration) is a fundamental factor, because of its impact on energy efficiency, thermal comfort of occupants and indoor air quality.

Accidental dispersion of toxic gas clouds may occur around industrial platforms or during hazardous materials transportation. In case of such a toxic risk, the best protection strategy is to remain inside a building and seek refuge in an airtight room identified as “shelter” until the toxic cloud has finally been swept off. This strategy called “passive shelter-in-place” also includes obstructing all external openings and turning off all mechanical ventilation systems

During the project QUAD-BBC, several ventilation systems have been studied in residential (individual house and collective dwellings) and non-residential (school, offices) and assessed by the evaluation of an IAQ multi-criteria.
These calculations have shown some typical evolution of pollutants in very tight low consumption buildings and can alert on some possible effects.

Building sealing may affect the total air change by decreasing the leakages and question the ability for ventilation systems to reach their goal of providing an acceptable indoor air quality. Improving energy performance must not impair indoor air quality.

Traditional architecture gives ideas to enrich modern architecture. In traditional architecture, local materials and renewable energy resources have been used. The courtyard was one of the traditional architecture solutions as a climate modifier. The inclusion of an internal courtyard in buildings design is attributed to the optimization of natural ventilation in order to minimize indoor overheating conditions.

LBNL Residential Diagnostics Database (ResDB) contains blower door measurements and other diagnostic test results of homes in United States. Of these, approximately 134,000 single-family detached homes have sufficient information for the analysis of air leakage in relation to a number of housing characteristics. We performed regression analysis to consider the correlation between normalized leakage and a number of explanatory variables: IECC climate zone, floor area, height, year built, foundation type, duct location, and other housing characteristics.

An emerging issue in Denmark is passive smoking in residential buildings where non-smokers are exposed to harmful smoke from their neighbours. There are various ways that smoke infiltrates from one flat to another. The air infiltration rate between two flats in a multi-storey building depends on its construction, tightness and age.

Demand Controlled Ventilation (DCV) is a well established principle to provide a certain indoor environmental quality, defined both in the terms of air quality and thermal comfort. This is accomplished by adjusting the supplied airflow rate according to a certain demand indicator, which conventionally has been the temperature or the CO2-concentration. When compared to schedule driven ventilation, application of DCV can lead to substantial energy savings. However, CO2 is the pollutant related to human occupancy and it does not provide any indication of so called building-related pollution.