The aim of this work is to study the influence of global heat transfer coefficient (Utot en W/m2.K) of the opaque walls (walls and roofs) and of the glazed walls (bays) on the annual consumption of heating, cooling and overall consumption energy. We analyze the number of hours of heating and cooling under operation with partial load and full load. Profiles of indoor temperatures are also given. The work is established on several office buildings defined according to a typology built within the framework of a study on energy savings in air-conditioned office buildings in France.

Many modern office buildings have highly glazed facades. Their energy efficiency and indoor climateis, however, being questioned.

The thermal exchanges between the buildings and its surroundings may be easily evaluated from balance equations. However, some parameters in the equations are prone to changesdue to decisions taken by the users at some time, and further decisions and even computations onthermal behaviour may be strongly affected by the users attitudes and actions. This can producewrong computation of energy consumption and savings, and then they have to be avoided. On theother hand, wrong actions of the users or misuses might produce uncomfortable conditions that aredifficult or expensive to handle.

The average air tightness of the ventilation ductwork in France is rather poor, corresponding toa 3A class. This is mainly due to air leakage in the fittings. Because of difficulties encounteredduring the implementation as lack of space, access problems or short time to proceed theinstallation, these fittings are not sealed enough, with mastic or adhesive tape.In order to limit this risk of leakage and to limit sealing operations on site, manufacturerspropose components equipped with joints. Some years ago, CETIAT has tested in itslaboratories different kind of such components.

In this study the question whether or not and to what extend ventilation and air cleaning can contribute to the reduction of exposure to environmental tobacco smoke in the hospitality industry is answered. First a literature review on ventilation and air cleaning technologies has been executed. Unfortunately, only a few papers reporting experimental data from the hospitability industry were available to answer the proposed question. Therefore a model describing the effect of different ventilation systems and building layouts has been set up.

The paper evaluates the potential work performance benefits of increased ventilation. We analysed the literature relating work performance with ventilation rate and employed statistical analyses. The studies included in the review assessed performance of various tasks in laboratory experiments and measured performance at work in real buildings. Almost all studies found increases in performance with higher ventilation rates. The studies indicated typically a 1-3 % improvement in average performance per 10 L/sperson increase in outdoor air ventilation rate.

Regular maintenance, such as the cleaning of filters, is important for the efficient operation ofresidential ventilation systems. The main objective of this study is to investigate effect of regularmaintenance on fan energy use and ventilation performance by using a test dwelling employingbalanced ventilation system. Experimental tests were directed with simulating the decrease of the airflow rates on terminals. Without cleaning, SFP based on the net air flow rate can indicate by 2.7 times compared with cleaned system.

Since the energy-crisis of the 70’ies, the trend goes to energy-saving constructions, that have strongly changed our way of building. The development of highly insulated houses in combination with manual window-airing leads to problems concerning a good q

Gas phase filters have been installed within the air handling unit of an HVAC system feeding 100 %fresh (outdoor) air to an office building. The filters efficiency for ozone (O3) and nitrogen oxides (NO2and NO) has been measured continuously over a one year period as function of time and outdoor airparameters (temperature, relative humidity). The results show that the filters efficiency varies alongtime and depends on temperature and relative humidity of air.

In this paper three real-world air-handling system problems are examined : the issues are discussed, troubleshooting techniques, solutions and lessons learnt are presented. The importance of design-phase integration of components is thus illustrated.