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A new solar façade concept based on transparent insulation and a selective absorber is proposed, tested and compared with conventional insulation and a non-selective type of absorber, respectively. The presented study focuses on an experimental non-ventilated solar type of façade exposed to solar radiation both in the laboratory and in outdoor tests. Due to the high solar absorbance level of the façade, high- and low-emissivity contributions were primarily analysed. All of the implemented materials were contrasted from the thermal and optical point of view. An analysis was made of both thermodynamic and steady state procedures affecting the proposed solar façade concept. Experimental full scale tests on real building components were additionally involved during summer monitoring. An indicator of the temperature response generated by solar radiation exposure demonstrates the outdoor performance of the façade is closely related to overheating phenomena. From the thermal point of view, the proposed transparent insulation and selective absorber concept corresponds to the performance of conventional thermal insulation of identical material thickness; however, the non-selective prototype only provides 50% thermal performance. The results of the solar-based experiments show that with a small-scale experimental prototype, approximately no significant difference is measured when compared with a non-selective absorber type. The only difference was achieved at the maximum of 2.5 K, when the lower temperature was obtained in the solar selective concept. At the full-scale outdoor mode, the results indicate a maximum of 3.0 K difference, however the lower temperature achieves a non-selective approach. This solar façade can actively contribute to the thermal performance of building components during periods of heating. [ABSTRACT FROM AUTHOR]

Wood has a long tradition of use as a building material due its properties and availability. However, it is very sensitive to moisture. Wood components of building structures basically require a certain level of moisture protection, and thus moisture monitoring to ensure the serviceability of such components during their whole lifespan while integrated within buildings is relevant to this area. The aim of this study is to investigate two moisture monitoring techniques promoting moisture safety in wood-based buildings (i.e., new structures, as well as renovated and protected buildings). The study is focused on the comparison of two electrical methods that can be employed for the nondestructive moisture monitoring of wood components integrated in the structures of buildings. The main principle of the two presented methods of the moisture measurement by electric resistance is based on a simple resistor–capacitor (RC) circuit system improved with ICM7555 chip and integrator circuit using TLC71 amplifier. The RC-circuit is easier to implement thanks to the digital signals of the used chip, whilst the newly presented integration method allows faster measurement at lower moisture contents. A comparative experimental campaign utilizing spruce wood samples is conducted in this relation. Based on the results obtained, both methods can be successfully applied to wood components in buildings for moisture contents above 8%. [ABSTRACT FROM AUTHOR]

A conversion of shortwave to longwave radiation heat transfer in building envelope system represents an substantial part in low-energy design campaing. For that reason, an experimental test sample of a novel solar façade element based on a Transparent Insulation Material (TIM) with a selective and a nonselective absorber was developed. The investigated element is a part of an opaque lightweight structure of a building envelope. The capability of one widely used Building Energy Simulation (BES) tool is analyzed in terms of its ability to model the performance of the TIM façade element. The good consistency between the simulation results and the experimental data obtained specifically via cooling period indicates that the reference simulation model based on high emisivity of solar absorber was reliable when predicting the energy performance of TIM based façade models. However, the low emissivity of solar absorbers in the façade cavity gives rise significant limitations. They were identified concerning the BES calculation methods and modeling principles. The computational results are significantly underestimated in case of low emissivity internal surface. The methodology developed in this study is expected to provide a reference for simulating the thermal and energy performance of TIM-based building elements with different solar absorbers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Analyses are conducted focused on climate adaptive reactions of BiPV facade system. • System's performance prediction is relevant for energy-efficient buildings. • Optimisation techniques yielded an increase in total thermal and energy performance. Ventilated building-integrated photovoltaic (BiPV)/phase-change material (PCM) façades have been applied and validated in building energy simulations; however, the dynamic thermal response of these façades has not been investigated. Notably, performance predictions and simulations for systems featuring natural airflows in the façade cavity are important for guiding the decision-making for energy-efficient buildings. To address this challenge in literature, in this work, numerical analyses were conducted, focusing on the climate adaptive reactions of a BiPV façade system coupled with a latent thermal energy storage system, based on a PCM. Numerical methods for determining the PCM heat transfer were evaluated, including their limitations. The thermodynamic reactions of two BiPV façade concepts were comparatively studied using two simulation domains: building energy simulations and computational fluid dynamics. The reliability of the theoretical methods was also evaluated. Good agreement between the simulation results and experimental data was noted through dynamic outdoor tests, empirically validating the study; standard statistical indicators were calculated and employed to assess the consistency between the experimental and simulation results. The used numerical approach can reliably predict the thermo-responsive capabilities of PCM-based BiPV façades with respect to the overall tendencies. The parameter variation techniques revealed modifications in the overall thermal and energy performance of the façade system. The most undesirable instance of overheating was predicted when using RT27; therefore, the PCM is considered inappropriate in this case. [ABSTRACT FROM AUTHOR]