Moisture control design has to respond to all relevant hygrothermal loads

Moisture related damage is still a formidable cost factor in the building sector. Besides installation deficiencies, moisture control design failures are the most frequent reasons for moisture problems. Therefore, adequate moisture control analysis has become the key for sustainable buildings. However, by focusing on vapour diffusion only other important moisture loads such as driving rain, construction moisture or air infiltration are mostly neglected. Therefore, international moisture control standards often refer to simulation models for more realistic analysis, leaving many practitioners wondering how to handle these tools. To overcome this dilemma, the updated German moisture control standard has introduced a three-pathway approach for design evaluation: 1 st deemed to satisfy list, 2 nd restricted Glaser calculation and 3 rd fully fledged hygrothermal simulation. The third pathway includes the option to account for small leaks or imperfections in building envelope components. Guidelines in other countries are also embracing similar moisture control approaches which gives hope for more durable and sustainable building design. To reach this aim, moisture control should also become an integral part of the design process instead of a secondary chore.

Recent progress on hygroscopic materials for indoor moisture buffering

Once in contact with the indoor air, hygroscopic materials can moderate the indoor humidity fluctuation by adsorbing or releasing water vapour, and then improve the moisture regulation and thermal management of buildings. It is desirable to explore the characterized properties of these materials about moisture buffering behaviour. In this regard, we review various hygroscopic materials used for the built environment control. The hygrothermal properties of hygroscopic materials often can be characterized by some parameters, such as water vapour adsorption/desorption capacity, water vapour adsorption/desorption rate, water vapour diffusion coefficient, and so on. To provide an insight on the existing research on humidity control materials, different research studies and the recent progress on humidity control materials have been summarized. The materials include traditional and conventional building materials, some natural materials, and novel humidity control materials. Besides, the relevant parameters are considered as well as the improvement suggestions to enhance the application of humidity control materials in building environments. Finally, new multifunctional materials and intelligent moisture control materials together with the corresponding systems are collated to summarize the latest research trends. The overview of the application of hygroscopic materials can provide current and future researchers guidelines for the science-oriented design of moisture control systems for new energy-efficient buildings.

Measuring and modeling moisture environment in underground metro stations during commissioning stage: A case study

Due to the humid underground environment, underground metro stations often have internal condensation issues, especially during the commissioning and initial operation phases, and these issues will have a negative impact on the equipment operation and building life. This study aims to solve the issue by 1) identifying common areas with condensation risks based on on-site measurements and numerical simulation methods, and 2) proposing effective dehumidification solutions for the moisture control of stations. By on-site investigating the characteristics of the station’s moisture environment and numerical assessing the effects of two different dehumidification strategies, it has been found that 1) for Tianjin, during most times in summer, the air temperature of the station in the commissioning phase was maintained relatively stable, but with significantly changing humidity; 2) the relative humidity on the platforms was higher than 80% for almost 30% of the testing time, and the surface of the upper structure of platform doors having a high risk of condensation; 3) the dehumidification effect of industrial dehumidifiers was found to be better than that of increasing exhaust air volume. The authors hope that the research could aid the decision on dehumidification strategies and provide guidance for further moisture control in underground stations. Practical Application This article analyzed the moisture environment of the underground metro stations in the commissioning phase and conducted a numerical approach to assess the condensation risk. Potential dehumidification solutions including increasing the exhaust air volume and using industrial dehumidifiers have been proposed, and their effects have been investigated and compared. The authors hope that this research can aid the decision on dehumidification strategies for facilities maintenance and provide a guidance to further moisture control in underground stations.

Smart Irrigation System for Indian Agriculture

Technology plays a very crucial role in the field of agriculture. By the help of automation, a procedure or process can be executed without any or minimal human assistance. This project is an automation of farm irrigation and soil moisture control by Arduino using moisture sensor. This automatic irrigation system determines the moisture content (by measuring resistance) with the help of the sensor which senses the moisture content of the soil and switches the pump on automatically whenever the power is kept on. Agriculture has a long history in India, dating back to ten thousand years. It is a source of employment of many Indians and has great impact on the economy of the country.

Combined Effect of Superabsorbent Polymers and Cellulose Fibers on Functional Performance of Plasters

Plaster has, from ancient times, been used as a decorative material. However, the advances in materials engineering such as thermal and moisture control provide new opportunities. Superabsorbent polymers (SAPs) have been found to possess passive moisture control that may find utilization in modern buildings. However, the main drawback is associated with a limited number of applicable SAPs due to mechanical strength loss. In this regard, concurrent utilization of cellulose fibers may provide additional benefits linked with the reinforcing of plaster structure and preservation of superior hygric properties. In this regard, this study investigates the combined effect of SAP and cellulose fibers on the material properties of cement-lime plaster in terms of its mechanic, thermal, and hygric properties. To access the capability of such modified plasters to control the interior moisture fluctuations, the moisture buffering value is determined. Obtained results show the effect of both applied admixtures on material performance, whilst the synergic effect was most obvious for humidity control accessed through the moisture buffer coefficient.