moisture

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.

The non-uniform behaviour of the air inside a room, which is important in comfort analysis, can be evaluated by zonal models. While not as fine-grained as CFD simulation, they do give useful information about temperature and moisture distributions that is not available from lumped-parameter models. Therefore, we have developed a tool, called SimSPARK, to automatically build dynamic zonal simulations of a building zone.

Radon concentration in a crawl space remained at the same level during autumn ( 756 Bq m-3 ) and inwinter ( 767 Bq m-3 ) because both air exchange rate and negative pressure (measured across thefoundation wall) increased after a installation of a new ventilation system in the crawl space. Inaddition, relative humidity and water content remained constant in the crawl space air during the sameperiod of time. Radon entry rate was explained by the pressure difference across the crawl space wallwith percentages of 51 % (winter) and 76 % (autumn).

The measurement of moisture in building fabrics has been of interest for many years due to thepotentially devastating consequences of moisture problems within buildings. A range of potentialtechniques are available with which to measure the moisture content of building fabrics in-situ and thispaper focuses on one particular technique, the thermal dual-probe. Note that this method is distinctfrom the single probe technique. Essentially, a short pulse of electrical energy is applied to a wirewithin the heating needle.

Relative humidity is one of the most important parameters which have an influence on human comfortand indoor air quality. Materials exposed to the air can absorb and desorb moisture and thereforeinfluence the relative humidity level. However hygroscopic materials are not always taken into accountin building energy performance simulation codes. The objective of presented work was to improvepredictions of the indoor relative humidity in a well known energy simulation tool TRNSYS.

We already have had theoretical model to predict temperature and humidity variations in a room. Manyworks have estimated the accuracy of the numerical model, but they might be influenced by the airmovement. Thus, theoretically the temperature and humidity variations should be solved with airmovement in a room. In this paper, I calculated the minute temperature and moisture distributions in aroom which has the moisture buffering effects by the porous walls. The room space is regarded asrectangular box which has two hole, inlet and outlet for ventilation.

Indoor humidity is an important parameter influencing the occupants’ perception of indoor air quality, and is also a cause of harmful processes that may occur on surfaces of materials, such as cracking of walls or microbiological growth. Building material

Heat and mass transfers in building materials influence the thermal properties and performances ofthe materials more especially as they are porous. This paper deals with the case of various porousbuilding materials (Aerated Autoclaved Concrete, Hemp Concrete and Vertically Perforated Brick)studied by an experimental approach. A cell of exchange makes it possible to impose on a sample,gradients of temperature and relative humidity variables as function of time. The performances ofthese materials are thus deduced from the evolution of T and %RH in several positions.

Nevertheless the proven benefit of a cyclist helmet in preventing serious head injuries whena crash occurs, many cyclist still refuse to wear a crash helmet. The main reason for not wearing acyclist helmet is the sensation of discomfort encountered when wearing one. This paper evaluates and analyses - for the first time - both local and global temperature levels and moisture production in order to obtain insight in the interaction between both mechanism, as a response to differences in effort level, air velocity and air temperature, and how to improve its thermal comfort features.

This paper sums up a longitudinal study carried out on a group of students and teachers in a remediated moisture-damaged school. Registration of subjective data (questionnaires) and objective data (nasal histamine reactivity) has been made. Results and discussion are presented.