This paper is divided into tree main sections, ‘Introduction to natural ventilation’, ‘Examples, strategies and results’ and ‘Energy consumption’. In the first section a general introduction to natural ventilation is given, including the three main princi

This paper describes current work to undertake a market assessment of the potential for the application of Passive Downdraft Evaporative Cooling (PDEC) to new and existing buildings in Southern Europe. The work is carried out as part of a European funded ALTENER project focussing on solar and passive ventilation for urban buildings. PDEC is a technique that may potentially become a substitute for conventional air-conditioning. The technique avoids the need for ductwork, fans and suspended ceilings, and reduces the need for refrigerant based cooling.

In moderate climates, one promising feature to reduce the energy demand of office buildings for air conditioning without reducing comfort is passive cooling by night ventilation. An office building has been designed, realised and monitored for a long time period in the framework of the German research programme solar optimised buildings. The night cooling of the office building has been realised by natural ventilation.

The applicability of natural ventilation depends strongly on climate. The potential of natural ventilation represents a measure of the feasibility of natural ventilation in a specific climate. A quantitative measure of this potential, expressed in degree-hours, may be estimated based on adaptive thermal comfort and monthly mean temperature. Degree-hours for natural ventilation represent the sum of the degree-hours for cooling saved by using natural ventilation when adaptive thermal comfort is considered.

Nowadays the awareness concerning the environmental pollution and the demand of transparent facades in architecture, lead research in finding new solutions to increase the energy performances of the building and the installations as well. Among those, different kind of Double Skin Facades have been studied and several laboratories are still working on them to find a suitable way to apply this technology in buildings.

This paper considers an ideal naturally ventilated building model that allows a theoretical study of the effect of thermal mass associating with the non-linear coupling between the airflow rate and the indoor air temperature.The thermal mass number and the convective heat transfer air change parameter are suggested to account for the effect of thermal mass heat storage and convective heat transfer at the thermal mass surfaces. The new thermal mass number measures the capacity of heat storage, rather than the amount of thermal mass.

Studies on buildings have shown that airtightness and insulation increased in family buildings and detached houses too, due to new thermal regulations. In the same time, studies concerning health and indoor air quality have shown that the need of fresh air will increase too.

This paper describes the results of a collaboration study between ENTPE-LASH and LEPTAB within the framework of the IEA Annex 35 “Hybrid Ventilation in New and Retrofitted Buildings”. The aim of the work is to carry out a cross-simulation study and identi

Ventilation is one of the most important measures to dilute indoor air pollutants. In order to maintain a clean indoor air environment, not only the total ventilation rate of the building but also the distribution of outdoor air to each area must be taken into consideration. A performance evaluation of the combined system of air supply from the crawl space and hybrid exhaust ventilation with a small fan and damper has been investigated. This investigation was undertaken over a heating season using a full-scale test house.

To evaluate the impact of the natural ventilation of the air cavity in the prototype of the glazing system being studied in the frame of the project SOLVENT, funded in part by the Commission of the European Union, a prototype of a reversible naturally ventilated glazing system. The system consists of a double (clear and tinted) glazing. In the summer position the tinted glazing is in the outer position and the cavity is open to the outside air at both top and bottom extremes.