Smart irrigation systems play a crucial role in water management, particularly in urban greening applications aimed at mitigating urban heat islands and enhancing environmental sustainability. These systems rely on soil moisture sensors to optimize water usage, ensuring that irrigation is precisely tailored to plant needs. This study evaluates the performance of four commercially available capacitive soil moisture sensors—TEROS 10, SMT50, Scanntronik, and DFROBOT—across three different substrates under controlled laboratory conditions. A total of 380 measurements were conducted to assess sensor accuracy, reliability, and the influence of insertion technique on measurement variability. Results indicate that while all sensors adequately cover the moisture ranges critical for plant health, their accuracy varies significantly, highlighting the necessity of substrate-specific calibration. TEROS 10 exhibited the lowest relative deviation and highest measurement consistency, making it the most reliable among the tested sensors. DFROBOT, despite being the least expensive, performed comparably to SMT50 and Scanntronik in certain conditions. The findings provide valuable insights for selecting and calibrating soil moisture sensors in smart irrigation applications, ultimately contributing to improved water efficiency, plant vitality, and sustainable building-integrated greenery.

This paper investigates the potential use of natural materials and elements for stabilizing indoor humidity levels, focusing on creating healthier living environments in buildings. Unstable indoor microclimates, particularly extreme humidity levels, can negatively affect human health by causing issues such as condensation, mold growth, or dry mucous membranes. In this work, we explore how sorptive materials can maintain indoor humidity within the optimal range of 40–50%. The aim is to identify optimal solutions for moisture control using passive elements, such as unfired ceramic components, which demonstrate high sorption activity within the 35–55% relative humidity range. These elements can effectively absorb moisture from, or release it back into, the indoor environment as needed. Five clay types based on different clay minerals were analyzed in the research in order to assess how their structures influence moisture adsorption behavior. These elements can be combined with green/active elements and standard measures, such as ventilation or targeted room air exchange, to improve indoor humidity regulation. The evaluation of the results so far indicates that the use of clay-based elements in the interior offers a sustainable and natural approach to maintaining optimal indoor microclimate conditions. The slab elements from all 5 clay formulations investigated effectively support indoor humidity stabilization.

Thermal insulation materials play a vital role in minimising energy loss in building operation and also affect the amount of greenhouse gas emissions associated with heating and cooling. In this context, it is becoming an increasingly important milestone to find suitable thermal insulation materials that not only meet the technical requirements but also minimise their environmental impact. The trend towards the use of eco-friendly materials for thermal insulation reflects the construction industry’s desire to contribute to environmental protection and the transition to more sustainable models of building construction and renovation. For more than 20 years, a number of research teams have been investigating the possibility of replacing synthetically produced materials such as mineral wool and polystyrene foam with natural fibre-based insulation materials. These alternatives include wood as a traditional, easily renewable raw material. This, together with the low energy intensity of processing and manufacturing wood materials, contributes to its low carbon footprint. Compared to traditional synthetic insulation materials, which are often energy intensive to produce, wood is a more environmentally friendly choice. However, with many European countries now facing a potential shortage of higher quality wood, it is necessary to look for alternative sources of wood, including in the field of thermal insulation materials, materials with a lower carbon footprint that can be produced from lower quality wood or from wood waste that would otherwise only have an energy use. The paper is devoted to the study and use of suitable wood waste and secondary raw materials from spruce wood (coarse wood chips, sawdust and wood flour) for the development of modern thermal insulations with the aim of an environmentally friendly and less energy-intensive production process compared to conventional insulants.

In the validation of microclimate simulation software, the comparison of simulation results with on-site measurements is a common practice. To ensure reliable validation, it is crucial to utilize high-quality temperature sensors with a deviation smaller than the average absolute error of the simulation software. However, previous validation campaigns have identified significant absolute errors, particularly during periods of high solar radiation, possibly attributed to the use of non-ventilated radiation shields. This study addresses the issue by introducing a ventilated radiation shield created through 3D printing, aiming to enhance the accuracy of measurements on cloudless summer days with intense solar radiation. The investigation employs two pairs of sensors, each comprising one sensor with a ventilated and one with a non-ventilated radiation shield, placed on a south-oriented facade with two distinct albedos. Results from the measurement campaign indicate that the air temperature measured by the non-ventilated sensor is elevated by up to 2.8 °C at high albedo and up to 1.9 °C at a low albedo facade, compared to measurements with the ventilated radiation shield. An in-depth analysis of means, standard deviations, and 95% fractiles highlights the strong dependency of the non-ventilated sensor error on wind velocity. This research underscores the importance of employing ventilated radiation shields for accurate microclimate measurements, particularly in scenarios involving high solar radiation, contributing valuable insights for researchers and practitioners engaged in microclimate simulation validation processes.

Due to its ecological and financial benefits, earth building has gained global attention, with earth bricks being extensively used. Shrinkage and crack development have a considerable impact on the performance and quality of earth bricks. This study employs laboratory experiments to examine the shrinkage behavior of earth bricks reinforced with wheat and barley straw. In addition to this, the impact of cement and gypsum additives is examined. The obtained results indicate that increased fiber content reduces crack formation effectively. However, higher levels of cohesive soil have been shown to have a negative influence on shrinkage behavior. In general, higher fiber contents contribute to the improvement of earth brick performance. These findings offer useful insights for improving the composition and characteristics of reinforced earth bricks, resulting in enhanced performance and quality in sustainable construction practices.

There is an increasing demand for green plant walls in indoor environments because of their multifaced benefits, such as aesthetic appeal, indoor air quality improvement, or psychological well-being. Mosses are believed to be excellent for these walls due to their easy application and maintenance. However, so far there is no evidence for their indoor survival. In this study, we tested the moss species Hypnum cupressiforme, Bryachythecium rutabulum, Eurrhynchium angustirete, Thuidium tamariscinum, Streblotrichum convolutum, Syntrichia ruralis, and Ceratodon purpureus for indoor use in living moss walls. We evaluated their vitality through the monitoring of leaf coloration over a twelve month period, subjecting them to varying temperature ranges (14–20 °C), humidity levels (60–100%), and diverse irrigation methods (drip and spray irrigation, 300–1500 mL per day) within controlled climate chambers. Depending on the combination of these variables, mosses survived up to six months. Hypnum cupressiforme and Ceratodon purpureus performed best. However, as the time span of survival was limited, the use of living mosses for indoor purposes at the current stage cannot be recommended. An additional problem is that the requisition of living material such as in the culturing of moss under horticultural conditions is difficult and harvesting from natural environments is detrimental to most habitats.

The use of renewable building materials in construction is crucial to minimising the environmental impact of new buildings. Bio-based building materials have a wide range of positive properties, many of which are due to their hygroscopic behaviour. The purpose of this study is to investigate the hygrothermal performance of chopped straw, sheep’s wool, and cellulose insulated timber frame external wall assemblies in the presence of air leakage and high indoor relative humidity. For this purpose, tests with different moisture contents, overpressures, and defects in the airtight layer were carried out in an outdoor test stand over a period of 18 months. The results were compared with a conventional mineral wool insulated construction. Both sheep’s wool and cellulose are particularly fault-tolerant insulation materials in combination with timber frame constructions. All three bio-based insulations, despite defects in the airtight layer, showed no mould-prone moisture content. An installation level insulated with sheep’s wool can increase the fault tolerance of constructions with insulation made of hygric and more sensitive building materials. For chopped straw and cellulose, the measured U-value was lower than expected. Further in situ measurements of bio-based structures are important to gain confidence in their hygrothermal behaviour and to increase their use in multi-storey construction.