Airtightness of French dwellings: results from field measurement studies.

A field measurement study of the airtightness of 73 - less than 5 year old - French dwellingswas led between 1999 and 2000. Buildings have been selected and classified according to theconstruction structure, the thermal insulation and the occupancy mode. Using a fandepressurizationtechnique, we assessed the air leakage rate of each dwelling with twodepressurization tests. Meanwhile quantifying air leakage rates, we observed qualitatively themost frequent locations of air leakage paths using a smoke detection method and infraredthermography.

Air quality and ventilation rates in schools in Poland - requirements vs reality.

The relationships between indoor environment and health, well being and ability to acquire knowledge are unquestionable. These are the reasons why in many countries a high level of indoor environment is required in school buildings. The goal of the paper is to compare the real state of the environment in classrooms in Poland with accepted requirements and standards. The evaluation of the existing situation is based on indoor environment measurements in 28 classrooms in Warsaw.

Quantifying ventilation needs in Local Authority housing - a case study.

A Tool Kit was developed to assess indoor air quality. The Tool Kit was designed to be robust, reliable, universal and to provide data that could be linked with other studies assessing health, social factors and building conditions for any given locality. A case study using the Tool Kit to assess 116 Local Authority houses is described.

Experimental testing of a ventilated roof component for energy saving in cooling.

A Ventilated roof component was built and tested in the outdoor testing facilities (Test Cells) of CRES, Greece. A conventional Greek roof structure of the same area was also installed in the roof of the Test Cell allowing simultaneous measurements in order to perform a comparative study of the performance of the two parts. Different configurations in the Ventilated roof were investigated, like ventilation air gap height and application of a radiant barrier. The tests carried out under summer weather conditions will be discussed in this paper.

Typology of hybrid ventilation systems and practical examples.

This paper aims to identify major characteristics of hybrid ventilation systems, whereby a clear distinction is made between ventilation for Indoor Air Quality control and ventilation as part of a strategy for control of thermal comfort in summer. The aim is to identify the major differences between the various approaches and to develop some kind of rationale. Various building projects are used as illustration for the classification.

Ventilation performances in French dwellings: results from field observations and measurements.

This paper presents a recent field measurement study undertaken in 1999 on 73 recent Frenchdwellings. The study presented the opportunity to assess the conformity and the performancesof the dwelling ventilation systems and to assess the impact of infiltration on airchange rates.The following aspects were analyzed : (1) the type of ventilation facilities in the dwellings ;(2) the defaults in the installed systems and in their operation ; and (3) the measured air flowrates, as compared to the French standard required levels.

Validation of a computational fluid dynamics simulation of a supply air 'ventilated' window.

A currently unresolved problem in building design is the paradox between increasing demandfor good thermal insulation, and the requirement for ample levels of ventilation, to maintain ahealthy indoor environment. A possible solution to this problem is a supply air ventilatedwindow. This utilises an airflow between panes to pre-heat ventilation air to the building, andto reduce thermal convection losses thus reducing the window U-Value. At the base of thewindow is a vent to the external environment, allowing air inflow.

The use of heat pumps to induce airflow on hot days in otherwise passive ventilation systems.

The paper presents results from a wider study into providing displacement ventilationin urban areas by taking air into buildings from the top without the use of fans.Results from large scale experimental work are given. These results indicate thatventilation airflows can be induced using gravity chillers and heaters in conditionswhere this type of installation would otherwise fail. The paper also describes initialexperiments undertaken to see how far the same equipment can be used in heatrecovery.One test installation is modelled using a proprietary zonal model.

The role of simplified ventilation modeling for the application of low energy design: a library case study.

This paper discusses how simplified thermal and ventilation tools could be used during thefeasibility study of buildings to demonstrate the advantages of natural and low energyventilation strategies. The paper focuses on local authority library buildings in South-EastEngland and two simplified tools were used; one using a dynamic thermal simulation andventilation method and another based on the admittance method. The prediction of both toolswere compared with measured temperatures from an existing library that has a knownoverheating problem.

The influence of variations in base temperature over the calculated ventilation energy demand.

The heating degree-days method is widely used for calculation of the air change heating energydemand. However, different countries perceive different values for base temperatures due todifferent insulation levels and internal loads, decreased infiltration rates through tighterconstruction practices, and low temperature settings in efforts to reduce energy consumption.This has always made it difficult to make accurate comparisons for heating energy demandbetween different countries.