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The paper introduces a novel method for risk assessment and preventive conservation of organic hygroscopic cultural heritage objects. The method is based on the analysis of the historic climate that is established in the European Standard EN 15757:2010. This new approach enables interpreting visible damage and assessing cause–effect relationships and it finds practical application in improving conservation strategies for real life buildings and objects. The paper investigates how it may be advantageous to reconstruct the historic climate back in time to obtain sound information about the target relative humidity (RH) level and the domain of RH fluctuations that can be considered safe for conservation. The method was applied to an inlaid wooden choir in the basilica of S. Giustina, Padua, Italy. The past indoor climate has been reconstructed over the whole life of the object, built in 1477, with documentary proxy data, instrumental readings and building simulation. Winter has been found to be the most critical season for the mechanical stress and wood yield. For the future, the indoor climate has been simulated until 2100 to timely devise preventive conservation measures to reduce the risk induced by climate change. Finally an evaluation of uncertainties has been considered. [ABSTRACT FROM AUTHOR]

Thermal comfort is one of the many aspects that affect human well-being and productivity. There is an increasing interest in understanding occupants’ requirements for maintaining the indoor comfort range while minimizing energy wastage. In this paper, a thermal perception map was developed for residential buildings in the humid tropics of Malaysia using logistic regression. Sharma and Ali's [1] concept was used for the elaboration of the thermal comfort map. This map helps in exploring the effect of climate changes on subjects’ thermal perceptions at various indoor air temperatures. The thermal comfort map should be useful for researchers in order to accurately estimate the required energy for maintenance of comfortable temperature. [ABSTRACT FROM AUTHOR]

The climate in Greenland is cold which means that living inside the heated space requires quite some energy. To avoid large heat losses and cold discomfort, building envelopes are often sealed, which reduces natural infiltration. The combination of reduced infiltration and lack of mechanical ventilation results in low air change and thus elevated concentrations of indoor pollutants. In cold Arctic regions where people spend most of their time during long winters indoors is the effect of poor indoor air quality (IAQ) on occupants' health and comfort considerable. A cross sectional study in 79 dwellings was performed in the town of Sisimiut. The aim was to investigate the indoor climate in Greenlandic dwellings. Temperature, relative humidity (RH) and CO 2 concentration were measured in several rooms in each dwelling. This paper presents the results from measurements in bedrooms. CO 2 concentrations above 1000 ppm and difference in absolute humidity between indoor and outdoor air above 2.5 g/kg as indicators of insufficient ventilation were found in 73% of the bedrooms. The situation was significantly worse dwellings build after 1990. Although the average winter additional moisture was higher than 2.5 g/kg, the RH was low (mean RH = 26%). In summer, 19% of all bedroom temperatures were above 26 °C despite the low outside temperatures. To avoid possible escalation of health problems related to IAQ in the future and to increase comfort of the occupants, properly designed ventilation systems should be introduced in Greenland. [ABSTRACT FROM AUTHOR]

Abstract: Stack ventilation and wind-induced ventilation are the two main methods for inducing natural ventilation. Stack ventilation by itself cannot create enough air flow to achieve good indoor air quality for building occupants under hot and humid climatic conditions. The low performance of stack ventilation in hot and humid climate is due to the low temperature differences between indoor and outdoor temperature of a building. On the other hand, the wind-induced ventilation method performance is independent of low temperature difference. Therefore, it has potential use to improve the indoor air quality for buildings in the hot and humid climate. This paper examines the wind-induced natural ventilation tower performs under hot and humid climate. The study reveals that the wind-induced ventilation tower has higher extraction airflow rate comparing to other wind ventilators in the market. Analysis shows the wind-induced natural ventilation tower can produce high air changes per hour (ACH) for indoor building environment in the hot and humid climate. Study results also show the wind-induced ventilation tower''s extraction flow rate is 10,000m3/h at external wind velocity of 0.1m/s. With the same external wind velocity, it produces average of 57 ACH. The results of this study will be useful for designing wind-induced natural ventilation tower in hot and humid climate. [Copyright &y& Elsevier]

Abstract: The coupled heat, air and moisture transfer between building envelopes and indoor air is complicated, and has a significant influence on the indoor environment and the energy performance of buildings. In the paper, a model for predicting coupled multi-zone hygrothermal-airflow transfer is presented. Both heat and moisture transfer in the building envelope and multi-zone indoor airflow are simultaneously considered; their interactions are modeled. The coupled system model is implemented into Matlab–Simulink, and is validated by using a series of testing tools and experiments. The new program is applied to investigate the moisture transfer effect on indoor air humidity and building energy consumption in different climates (hot-humid, temperate and hot-dry climates). The results show that not accounting for hygrothermal effects in modeling will result in overestimation of energy costs for hot and humid climate situations and possible over sizing of plant leading to inefficient operation. [ABSTRACT FROM AUTHOR]