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Case Study on Ventilation for Improving the Hygrothermal Behaviour of Emergency Temporary Housing under Japanese Conditions

Emergency Temporary Housing units consisting of a light-gauge steel brace construction were built following the Great East Japan Earthquake of March 11, 2011 (see Appendix). About 30,000 of these units are still in service following a delay in rehabilitation and reconstruction. The heat bridge portion in this kind of construction causes surface condensation in rooms. In addition, condensation damage on the steel roof surface in the attic space is also relatively large.

Indoor humidity influenced by the stack effect in high-rise residential buildings

Interior-surface condensation on the glazed curtain wall of high-rise residential buildings is an important environmental issue in Korea. There are three causes of the surface condensation. One is the curtain wall frame materials, another is the generated moisture from residents' behaviors such as cooking and drying the laundry, the other is inadequate ventilation caused by stack effect.

Frost damage of roof tiles in relatively warm area in Japan - condensation on external surface

Even in relatively warm area in Japan, frost damage of roof tiles occurs. In this study, the influences of several factors on frost damage are considered from a thermal environmental point of view. Condensation on the external surfaces of roof tiles, which is caused by a temperature drop due to nocturnal radiation, is estimated as one of the most important factors to the frost damage. The frequency of condensation was calculated by a numerical analysis. The influence of the parameters, such as the inclination angle and the orientation of the roof, is investigated.

A Study on the Indoor Environment of the Main Building of the National Museum of Western Art, in Japan, for the Development of a Retrofit Scheme

The National Museum of Western Art is the only work of Le Corbusier in Japan and 50 years have already passed since its construction. In order to maintain the museum’s value as a cultural asset, there is an urgent need to draft a thorough retrofit plan both to maintain the building’s function as an art museum and to restore Le Corbusier’s original design concept.

Moisture and Condensation in Residential Buildings in a Relatively Dry Region

It is not unusual to face moisture problems in buildings in cold climates and wet regions. It is, however, unusual to have the same problem in a relatively dry region such as Jordon, which has moderate weather conditions and mild winters. Nevertheless, a significant proportion of houses and residential apartments in Jordan are affected. The monitoring of inside air conditions, wall surface temperatures, ventilation and living style has shown that a high relative humidity (RH >75%) occurs at walls resulting in possible condensation.


Ventilation radiators, heat emitters where cold ventilation air is brought directly from outdoors into theroom via heated radiator surfaces, are becoming more and more common in Scandinavia. Becausethese systems combine both heating and ventilation several interesting aspects arise that may be usedto save energy and improve indoor thermal climate. The heating aspects in wintertime have beendiscussed in previous papers from KTH STH.

Indoor humidity modeling and evaluation of condensation on interior surfaces

In tropical humid climates, moisture and condensation on walls lead to significant damage of buildings. The purpose of this article is to present a numerical model to improve the prediction of internal humidity in buildings. Thermal simulation codes usually evaluate moisture due only to airflow transfers. The model presented takes into account the moisture transfers between walls and air inside a zone. It allows a forecast of the quantities of liquid condensed on a surface. An experimental comparison is presented to appreciate the improvement of the model.

Window condensation in historic buildings that have been adapted for new uses

Measurement were operated in Ottawa’s Laurier House (an historical house built in 1878 now being a museum) to determine the temperature and humidity conditions under which condensation occurs on ‘historic’ windows. Results lead to recommendations for oper

A ceiling condensing unit with Peltier elements for drying and cooling

A condensing device allows to avoid condensation on cooling ceilings in rooms with humid air. It uses thermoelectric modules in contact with the cooling panels. The pumped heat is transferred into the cooling ceiling to keep its temperature above the dew point. Tests have been performed in a full-scale chamber. A set of condensing units was mounted on a standard hydraulic cooling ceiling. The control of temperature is achieved by regulating the mass flow of the water. By this method the loss of efficiency of the cooling panels is fully compensated.

Interstitial condensation due to air leakage: A sensitivity analysis.

This paper presents an approach to evaluate the sensitivity of a roof design to condensation problems, given the uncertainty to achieve continuity of airtightness in practice. The approach consists of a repeated number of simulations with a 2D heat, air and vapour transfer model to predict the variation in roof moisture performance due to various discontinuities in roof geometry. The set of discontinuities is calibrated by comparing measuring data of roof airtightness to simulation results.