Abstract: This study reports a numerical analysis of the performance of green façades in different geographical locations and seasonal conditions. A mathematical model from a previous study is implemented and combined with the modified convective heat transfer coefficients from a recent study of the literature to simulate the transient heat transfer through bare walls and green facades with climbing vegetation. An implicit Finite Difference Method (FDM) based solver is used to perform the numerical simulations. Climate data are taken from relevant weather stations in Oslo and Rome and typical meteorological year (TMY) values are used for this purpose together with variable thermo-physical properties of air. An energy budget analysis reveals that the short-wave radiation term and convective heat transfer term are predominating compared to the other terms involved in the energy balance equation for summer time. The results show that the green walls are most effective in summer seasons with high levels of solar radiation, as most of the cooling effect is credited to the vegetation blocking the solar radiation. In cooler seasons, the benefit is less prominent. Furthermore, an analysis of the effects of the different models of convective heat transfer coefficients is presented.
Permalink: https://doi.org/10.3384/ecp2017631

Abstract: This study reports a numerical analysis of the performance of green façades in different geographical locations and seasonal conditions. A mathematical model from a previous study is implemented and combined with the modified convective heat transfer coefficients from a recent study of the literature to simulate the transient heat transfer through bare walls and green facades with climbing vegetation. An implicit Finite Difference Method (FDM) based solver is used to perform the numerical simulations. Climate data are taken from relevant weather stations in Oslo and Rome and typical meteorological year (TMY) values are used for this purpose together with variable thermo-physical properties of air. An energy budget analysis reveals that the short-wave radiation term and convective heat transfer term are predominating compared to the other terms involved in the energy balance equation for summer time. The results show that the green walls are most effective in summer seasons with high levels of solar radiation, as most of the cooling effect is credited to the vegetation blocking the solar radiation. In cooler seasons, the benefit is less prominent. Furthermore, an analysis of the effects of the different models of convective heat transfer coefficients is presented.
Permalink: https://doi.org/10.3384/ecp2017631

Abstract: This study compares building electric energy prediction approaches that use a traditional statistical method (linear regression) and artificial neural network (ANN) algorithms. We investigate how significantly occupancy rates and local environmental conditions, such as temperature, humidity ratio, solar radiation, cloud type, and wind speed, impact the actual electric energy consumption of a campus building for both working and non-working days. To analyze the degree of impact of each input data type element, an impact value factor was applied to these data sets. The results illustrate that the ANN modeling was more accurate and stable than the linear regression method in predicting the electricity consumption for working days. By impact factor analysis for working days, occupancy rates were found to strongly dominate the electricity consumption in the building, while temperature and humidity also affected the results. However, there were no accuracy differences between the two models in predicting electricity consumption on non-working days because different data type elements had similar impact on the non-working day results. The two models—linear regression and ANN with a Levenberg–Marquardt Back Propagation (LM-BP) algorithm—were able to meet the long-term and real-time hourly prediction requirements for electricity consumption of an actual building based on occupancy rates and local environmental conditions. The analysis of the input element changes on a macroscopic scale is helpful in predicting how each element influences electric energy consumption in buildings with numerical impact factor. The proposed ANN method with LM-BP algorithm can be used as a reliable approach, compared with the linear regression modeling, for predicting the electricity consumption of a building.
Permalink: https://doi.org/10.1016/j.scs.2020.102385

Abstract available via the hyperlink above

Abstract: The Book of Abstracts is from the BuildSim Nordic 2020 – International Conference Organized by IBPSA Nordic the 13th-14th October 2020 in Oslo. The conference was organized in cooperation between the Nordic chapter of IBPSA, and hosted as a virtual conference by OsloMet. The book of abstracts includes workshops papers on topics involving the use for integration of modeling tools for better building design, performance, and operation. The topics for the conference include (but are not limited to) • Building acoustics • Building Information Modelling (BIM) • Building physics • CFD and air flow • Commissioning and control • Daylighting and lighting • Developments in simulation • Education in building performance simulation • Energy storage • Heating, Ventilation and Air Conditioning (HVAC) • Human behavior in simulation • Indoor Environmental Quality (IEQ) New software developments • Optimization • Simulation at urban scale • Simulation to support regulations • Simulation vs reality • Solar energy systems • Validation, calibration and uncertainty • Weather data & Climate adaptation • Fenestration (windows & shading) • Zero Energy Buildings (ZEB) • Emissions and Life Cycle Analysis
Permalink: https://hdl.handle.net/20.500.12199/6424

Abstract: This paper presents a sensitivity analysis followed by an optimization to improve the performance of a ground source heat pump (GSHP) system for an office building located in Norway, for Oslo, Stavanger, and Tromsø climatic conditions. The ground source heating model was firstly validated by available measured data. The sensitivity and optimization simulations were conducted by using IDA ICE software and its integration with the GenOpt tool for optimization. The sensitivity results showed that the borehole depth was the most prominent parameter. Therefore, by increasing and decreasing the borehole length by 20%, for example for Tromsø climatic condition, the energy supplied by the top heating reduced by 22% and increased by 31%, respectively.
Permalink: https://hdl.handle.net/11250/2684036

Abstract: PCM enhanced wallboards on internal surfaces of building spaces is an attractive solution for improvement of thermal performance in buildings. This work deals with using a novel spackling compound as a primer coating material, from Gyproc Saint-Gobain, Sweden AB, in the inner walls of building envelopes for passive cooling and thermal comfort management. The spackling compound contains fillers, rheological additives and binding agents together with micro-encapsulated PCM. Experimental measurements and numerical simulations are performed for an office cubicle having 14 m2 floor area with and without PCM enhanced spackling material. PCM enhanced spackling has been applied on the internal walls and ceiling surface. The results show that a significant cooling effect could be achieved when covering walls and ceiling with PCM enhanced spackling directly exposed to the occupied zone. Furthermore, a parametric study shows that the PCM’s thickness, and the nighttime ventilation airflow rate and supply air temperature have considerable impact on the cooling performance.
Permalink: https://hdl.handle.net/11250/2684012

Abstract: This work reports a proper orthogonal decomposition (POD)-interpolation based prediction of indoor airows related to displacement ventilation. Steadystate computational uid dynamics (CFD) solution snapshots with varying relevant non-dimensional number are used to estimate the dominant POD coe _cients/modal amplitudes and POD modes. A cubic spline interpolation of the POD coe_cients is used to compute the solution for desired value of the non-dimensional number of interests. The veri_cation and validation of this data-driven procedure is performed considering a 2D mixed convection problem involving a horizontal channel with cavity heated from below for a range of Richardson numbers. On the other hand, CFD solutions for a standard displacement ventilation con_guration is used to decompose the ow _eld variables in terms of Archimedes number dependent POD coe_cients and associated space dependent POD bases. A detailed analysis of the CFD and POD-interpolated predicted ow-_eld variables for displacement ventilation cases, error estimates and the spatial structures of the POD modes are presented.
Permalink: https://hdl.handle.net/11250/2683230

Abstract: Preface. The BuildSim-Nordic 2020 conference is the first in a series of events with a long-term objective to establish a key biannual international conference in building performance simulation, with a strong focus on Nordic countries. The purpose is to create a platform for exchanging ideas, issues, and research findings that facilitates international collaboration and the meeting of minds between practitioners, researchers, and students. This book contains selected papers approved by the reviewers and the scientific committee of the BuildSim-Nordic 2020 conference, October 13th & 14th 2020. The conference was hosted by OsloMet University in Oslo, Norway, and organized in cooperation between the Nordic chapter of IBPSA, OsloMet and NORVAC. All submissions to the conference underwent a review process and presentation type was determined. Two blind reviewers evaluated each paper, a third reviewer was asked for evaluation in cases where the first two reviewers were not in good agreement. The selected full papers are of a high quality theoretical (scientific) nature. IBPSA-Nordic is a regional affiliate of IBPSA, the International Building Performance Simulation Association, for four countries: Denmark, Finland, Norway and Sweden. IBPSA-Nordic is linked to IBPSA-World association but acts as an independent organization.
Permalink: https://hdl.handle.net/11250/2684084

Abstract: Several studies underline the dramatic changes that are expected to take place in nature and environment due to climate change. The latter is also expected to affect the built environment. Particular emphasis is currently given to the impact of climate change on historical structures. Within this context, it is important to use simple methods and novel tools in order to investigate pecific case studies. In this study, the climate change impact on the hygrothermal performance of the log walls in a historic timber building is presented. The building under investigation is the Fadum storehouse, also known as ‘the coated house’, located in Tønsberg, Norway. The storehouse dates to the late 18th century. It has a particular design with the main features of stumps or piles up to which it stands and the ‘coating’ that covers its outer walls. The main damage of the construction is related to the biological degradation of the wood. The hygrothermal performance of the log walls, as well as the exterior and interior climate, have been monitored and the results have been used to validate a Heat, Air and Moisture transport (HAM) model. The validated HAM model is then used to examine the performance of the log walls for both current and potential future climate conditions. The transient hygrothermal boundary conditions serve as the input parameters to a biohygrothermal model that is used to investigate the biological deterioration of the building components. The findings reveal that currently there is no mould risk for the main body of the construction, which is in accordance with the visual inspection. The passive systems of the building are highly conducive to these results, since they protect it from driving rain and other sources of moisture and eliminate the potential impact of future climate change risk scenarios.
Permalink: https://doi.org/10.1051/e3sconf/202017215006

Abstract: This study explores approaches to evaluates correlation how significantly plug load data, occupancy rates, and local weather factors affect the actual electricity consumption of a commercial building in seasonal changes and it predicts electricity usage in buildings using four Back-propagation neural network (BP-NN) algorithms: Levenberg–Marquardt Back-propagation (LMBP), Quasi-Newton Back-propagation (QNBP), scaled conjugate gradient (SCG), and Bayesian regularization (BR). In order to evaluate the impact performance of each input parameter, an impact value was used for these experimental datasets. The results demonstrated that the artificial neural network (ANN) model using the LMBP algorithm has better performance in forecasting electricity consumption in a building. Compared to the other three ANN method results, the LMBP model represented better performance with a lower error rate of 1.07–2.23%. Through impact factor analysis, plug load data were found to highly impact the electricity consumption, and temperature had a significant impact in the summer. However, temperature did not largely influence the results in the winter because the gas boiler heating systems used in the building had little impact on the actual electricity consumption. These methods are helpful in analyzing input factors how each element influences energy consumption. The four proposed BP-NN methods can be used as reliable approaches.
Permalink: https://doi.org/10.1016/j.scs.2020.102321

Abstract: Straw bale constructions are considered as a promising solution towards the goal of decarbonisation of building sector. In particular, its use as an alternative thermal insulation and load-bearing material has been promoted. This study provide a thorough review of material properties of straw bale including mechanical, thermophysical and hygric. Furthermore, mechanical, hygrothermal, energy and acoustical performance as well as life cycle assessment of straw bale constructions are reviewed and discussed. The critical evaluation of the recent research confirms that straw bales can provide satisfactory results as thermal insulation material compared to conventional materials, while in parallel reflects a high potential for constructions with low embodied emissions. The potential of straw bale is tackled by the lack of consistent representation of material properties, which is controversial to the significant amount of the relevant scientific results that have been reported during the last years. This review provides a systematic framework that can function as basis for future research on straw bales as building material.
Permalink: https://doi.org/10.1016/j.conbuildmat.2020.120385

Abstract: This study evaluates typical faults occurring in demand-controlled ventilation (DCV) system and the impact on three output results: energy use, thermal comfort, and indoor air quality. The methodologies used in this study were qualitative interviews of selected Norwegian Heating Ventilation Air Condition (HVAC) system experts and numerical modeling using the building performance simulation tool IDA ICE. The faults deduced from the qualitative interviews were modeled as the fault’s different consequences to account for a large variety of faults. With a Norwegian school classroom as a case study, a local approach applying a one-at-a-time (OAT) simulation was used to perform an analysis of the extreme fault conditions that can occur. The results from the fault modeling demonstrated that greater attention is needed to avoid faults in the HVAC systems due to its impact on the indoor environment quality and energy efficiency of buildings.
Permalink: https://doi.org/10.1051/e3sconf/202017209006

Abstract: One of the main challenges in highly insulated buildings is the increasing share of energy demand for cooling. New solutions for low energy cooling are needed. Individual cooling by demand-controlled ventilation and use of ceiling mounted nozzles for cooling by higher air velocities could be an alternative. A laboratory study was designed to investigate thermal comfort and thermal sensation for elevated indoor room temperatures relevant to Norwegian summer climate; 24℃, 26℃ and 28℃ with a relative humidity set point of 40 %. Air flow was set to give air velocities of 0.25 m/s, 0.50 m/s and 0.75 m/s. 21 test persons were exposed to different air velocities in a cross-over study. Questionnaires on thermal comfort and thermal sensation were answered repeatedly. Jets from ceiling mounted supply air nozzles was shown to improve thermal comfort at 24 °C, 26 °C and 28 °C. In general, most test persons preferred low air velocity (0.25 m/s) at 24 °C, while high (0.5 m/s) or extra high (0.75 m/s) air velocities were preferred at 26 °C. At 28 °C, extra high or even higher air velocities were preferred.
Permalink: https://doi.org/10.1051/e3sconf/202017209002

Abstract: An increasing part of modern building’s energy demand is due to cooling. An ongoing research project investigates the possibility to reduce the energy consumption from cooling by utilizing an individually controlled active ventilation diffuser mounted in the ceiling. This study looks at thermal sensation and thermal comfort for 21 test persons exposed to an innovative user controlled active ventilation valve, in a steady and thermally uniform climate chamber. Furthermore, the relationship between biometric data from the test persons skin temperature and sweat, and the test persons thermal sensation scores has been investigated. Each test person was exposed to three different room temperatures in the climate chamber, 24°C, 26°C and 28°C respectively, to simulate typical hot summer conditions in an office in Norway. At a room temperature of 26°C it was possible to achieve acceptable thermal comfort for most test persons with this solution, but higher air velocity than 0.75 m/s around the test persons bodies at room temperatures of 28°C is required to ensure satisfactory thermal comfort.
Permalink: https://doi.org/10.1051/e3sconf/202017206001

Abstract: With the shortage of the energy and the improvement of people’s environmental requirements, it has received more and more attention to realize building energy efficiency through new energy sources. Trombe wall is a technology that uses solar energy and wind energy to enhance indoor natural ventilation, thereby achieving indoor temperature and humidity reduction and improving air quality. In this paper, the impact of rectangular fin arrays on the cooling performance of a combined solar system, consisted of Trombe wall, Solar chimney, and water spraying system (WSS), was experimentally investigated. Different fin types including copper, aluminum and brass fins were considered. The experimental room measuring 3m×2m×3m was located in Yazd, Iran, characterized with hot and dry climate. The cooling performance was assessed in terms of fin materials and the number of fins. The results showed that using water spraying system, the room temperature decreased up to 10°C. The cooling efficiency of the system with thermal fin increased up to 6%. Furthermore, the copper fin resulted in maximum cooling efficiency and more comfortable average room temperature than two other fin types.
Permalink: https://doi.org/10.18280/ijdne.150311

Abstract: Several energy programs worldwide have used building inspection to overcome the lack of knowledge on technical parameter that are needed to upgrade existing buildings to make them more efficient. Due to the large amount of existing buildings that require to be renovated, energy policies have introduced energy certification as a way to increase the renovation rate, by providing information on several benefits such as energy savings, indoor environment improvements and financial support. However, these procedures are often simplified due to the high cost that field measurements represent. The most common procedure for residential buildings is a walkthrough or visual inspection and the use of statistical data from a sample of buildings to estimate key characteristics. These simplifications can be seen in certification or labelling programs in order to analyse the building performance and to propose energy conservation measures. This study uses a case study to propose a method that in combination with building inspection can provided accurate data of the building performance and technical parameters such as U-values, ventilation rate, infiltration and internal load. The method as a firsts step tailored the information gather during the walkthrough in order to be used in the second step which is a calibration based on collected data from the smart meter. The study case corresponds to a wooden terraced dwelling located in Oslo, the set temperature during winter are different in certain rooms of the dwelling as well their operational schedules. The results show that the uses of smart meter data can effectively improve the results from energy certificate and labelling in existing building, allowing to provide quality information to homeowners and policy makers.
Permalink: https://doi.org/10.1088/1755-1315/503/1/012038

Abstract: A total of four strains of the ‘environmental superbug’ Pedobacter isolated from sludge produced at Norwegian drinking water treatment plants, were characterized by whole genome sequencing and antibiotic susceptibility assays. As with previous studies on members of this genus, we found that the isolates were multi-drug resistant, and that this resistance included clinically important beta-lactams, aminoglycosides and the fluoroquinolone ciprofloxacin. Using the minION sequencing platform (Oxford Nanopore Technologies) combined with HiSeq PE150 Illumina sequencing data, the four isolates were assembled into genomes of single contigs. Analysis of the genomes revealed potential genetic factors possibly underlying some of the specific resistances observed. Metallo-beta-lactamase activity was detected in one isolate, and the same isolate contained a putative metallo-betalactamase gene resembling pedo-2. Furthermore, several genes related to multidrug efflux systems were found using the resistance database CARD. Additionally, the present study extends our knowledge on the phylogeny of this genus, adding four new genomes to the existing 50.
Permalink: https://doi.org/10.1093/femsec/fiaa088

Abstract: The Energy Performance Certificate (EPC) has an especial feature for existing buildings, a Recommendation List of Measures (RLM) designed to improve the energy performance of these buildings. This feature has not been properly studied by researchers or policymakers, in spite of being one of the main tools that can encourage building owners to perform renovation activities. Considering the scarce research focusing on the recommendations list of measures, more information is needed in order to identify weaknesses, barriers and improvements of this tool. This is especially important since the European commitment to reduce their emissions in 2020 are far from reaching the proposed goals, mainly becouse of the low renovation rate. This critical review is based on the current literature mainly from reports delivered by the Commission and academic research. The study focuses on the requirement set by the directive, its current performance, barriers and improvements that can be made to take this tool to a level that can be effectively used by policymakers, certifiers and owners. The upgrade of the recommendation list of measure should strengthen their calculation methods and procedure from both local authorities and the Commission. This should be in line with the certifiers’ needs in order to do relevant work, including proper training, mandatory field inspections and tools. Lastly, financial policies and information should be implemented to accompany the certificate, ensuring that building owners interested in renovation have assistance and financial facilities or easy access to relevant information on this matter. The main conclusion of this study reveals that the regulatory framework could use some strictness in order to avoid ‘just enough’ implementations. Ambiguous definitions and too flexible obligations should be revised, especially cost-effectiveness and training for the certifiers. Attention on how to deliver the information to building owners should be increased, allowing them to understand the results, its implications and how to concretize renovation work through financial mechanisms, thus increasing the reliability of the EPC and the RLM.
Permalink: https://doi.org/10.1016/j.enbuild.2020.110065

Abstract: The unsteady aspect of turbulent flow structures generated by a shock-wave diffraction over double cylindrical wedges, with initial diffracting angle of 75°, are numerically investigated by means of two-dimensional high-fidelity numerical simulation. Different incident-shock-Mach numbers, ranging from transonic to supersonic regimes, are considered. Unlike previous studies where only the total vorticity production is evaluated, the current paper offers more insights into the spatio-temporal behavior of the circulation by evaluating the evolution of the instantaneous vorticity equation balance. The results show, for the first time, that the diffusion of the vorticity due to the viscous effects is quite important compared to the baroclinic term for low Mach numbers regimes, while this trend is inverted for higher Mach numbers regimes. It is also found that the stretching of the vorticity due to the compressibility effects plays an important role in the vorticity production. In terms of pressure impulses, the effect of the first concave surface on the shock strength has been quantified at both earlier and final stages of the shock diffraction process. Unlike the overpressure, the static and the dynamic pressure impulses are shown to be significantly reduced at the end of the first concave surface.
Permalink: https://doi.org/10.1016/j.actaastro.2020.02.017

Abstract: Shock-wave diffraction over double concave cylindrical surfaces has been numerically investigated at different flow regimes by varying the incident-shock-wave Mach number from Ms = 1.6 (transonic) to Ms = 4.5 (supersonic regime). The purpose of this study is to better understand the dynamics of shock-wave structure and the associated wave configurations. A mesh-independent solution is obtained and the flow is assessed through different physical quantities (transition angles, triple points trajectories, wall-pressure and skin-friction distributions, velocity and shock location). It is found that the transition angles, from regular to Mach reflection, increase with the Mach number. This phenomenon remains almost the same over both concave surfaces for weak Mach numbers (up to Ms = 2.5) and becomes relatively larger on the second surface for high Mach numbers. In terms of shock dynamics, it is found that by increasing the incident incident-shock-wave Mach number to Ms = 4.5, unlike the first reflector, the transition from a single-triple-point (STP) wave configuration to a double-triple-point (DTP) wave configuration and back occurred on the second reflector, indicating that the flow is capable of retaining the memory of the past events over the entire process. For the shock velocity, the velocity deficit is found to be increasing with increase in Ms. A best fitting scaling law is derived, to ensure a universal decay of the shock velocity depending on the flow parameters.
Permalink: https://doi.org/10.1016/j.actaastro.2020.01.025

Abstract: Selecting the most cost-effective retrofit interventions to achieve a significant reduction of energy use and CO₂ emissions in the building sectors is challenging, because a large number of possible retrofitting options should be analyzed. To remedy this and simplify the decision-making process, optimization may be adopted. This study developed an iterative optimization process by coupling a dynamic energy simulation software, IDA-ICE, and a generic optimization engine, GenOpt, through the Graphical Script module. This optimization process was applied to an office building located in the Nordic climate. Two scenarios were considered. In the first scenario, the optimal designs were achieved by minimizing the life cycle cost of retrofitting measures over a span of 60 years, while the building energy use for space heating and cooling were the constraints to satisfy the Norwegian passive house standard level. In the second scenario, the delivered energy to the building was minimized and the life cycle cost of retrofitting was limited to a predefined value. Two different space heating systems were used, radiator space heating and all-air systems. The optimization parameters included building envelope elements and heating and cooling set points (in the case of all-air system). The results showed that the specific life cycle cost could be reduced up to 11%, while the energy use for the space heating and space cooling was met according to the Norwegian passive house standards. The delivered energy to the building could be decreased by up to 55% in the second scenario.
Permalink: https://doi.org/10.1016/j.apenergy.2020.114929

Abstract: There is a growing awareness of the importance of indoor microbiomes for human health. Given their complexity, these microbiomes can only be adequately surveyed using high throughput sequencing techniques. Oxford Nanopore’s MinION is the newest third generation sequencing technology on the market. With its many advantages such as portability, user friendliness, simplicity, speed of sequencing and long read length, the technology is now an actual contender to established sequencing platforms. MinION’s main disadvantage is a relatively low read accuracy compared to several other platforms, although this is constantly improving. The present study, which appears to be the first of its kind, provides the results of a preliminary analysis of the microbial communities in indoor environments based on 16S rRNA gene amplicon sequencing, using both the Oxford Nanopore Technologies (ONT) MinIOn and the Illumina MiSeq DNA sequencers. At the level of family and above, there was no significant difference between the microbial compositions as revealed by the two platforms. However, at the genus, and particularly at the species level, the ONT MinION reported greater taxonomic resolution than Illumina MiSeq.
Permalink: https://doi.org/10.1038/s41598-020-59771-0

Abstract: Thermal energy storage with phase change materials (PCM) is a promising candidate to promote resource sustainability in buildings. The intelligent selection and usage of a PCM within the structure of a building poses a challenging engineering task due the highly dynamic nature of occurring heat transfers. This work features a step-by-step FEM modeling guideline to assist the design of building structures by means of a 1D heat conduction scheme. The phase change functionality is based on the apparent heat capacity method and extended by ordinary differential equations to account for the thermal hysteresis of materials with different melting and freezing temperatures. The set of equations is solved alongside with logical expressions representing a thermostat functionality to assess the external energy demand. Two proof-of-concept examples for PCM usage in typical Swiss and Greek wall structures are given.
Permalink: https://doi.org/10.1088/1755-1315/410/1/012114

Abstract: In recent years there has been a greater interest in developing new more sustainable solutions in the construction of buildings and in particular of large commercial and industrial buildings. Thisstudy analyses the feasibility and degree of sustainability of using cross laminated timber (CLT) as building material in industrial buildings in Nordic climate. An industrial building located in Eastern Norway, MAXBO Bjertnestangen, has been used as case study for the analysis. Two scenarios have been studied: i) the first analyses the existing industrial building (Scenario 1) built in steel, and ii) the second implies that the building components are replaced with CLT-elements (Scenario 2). For the structural analysis a commercial finite element method (FEM) code has been used and the results confirm that the CLT building achieves approximately equal mechanical and structural properties. For studying building physics in the two buildings, a commercial numerical simulation tool that couples hygrothermal with energy performance and uses the finite volume method (FVM) has been employed. The results show that it is possible to achieve a total energy saving of 3.3%, for the industrial building consisting of CLT-elements compared to the existing building. Furthermore, the life cycle analysis (LCA) shows that the total emission of CO₂-eq is 16.7% lower in the CLT building, however the building’s construction costs are higher 13% compared to the existing industrial building. Finally, an optimized solution has been proposed in which sandwich panels in the roof are combined with CLT in rest of the building. In this case, the difference associated with costs is narrowed to 3.3%, while the difference in the total emission of CO₂-eq stays still significant, i.e. 13.6%.
Permalink: https://doi.org/10.1088/1755-1315/410/1/012082

Abstract: The dwellings built between 1945 and 1980 have the largest energy demand in the EU, which by 2009 represented 70% of the final energy use in buildings. A great portion of these dwellings have not been retrofitted and most of them were not built with any energy efficiency measures, since most of the energy regulations were implemented after the oil crisis in the 1970s. The current renovation rate of residential buildings has not reached targeted goals, due to the numerous barriers that arise in the renovation process. The evaluation and labelling of existing residential buildings represent a big challenge, and the lack of geometric information on buildings is one of the main issues hindering an assessment through simulations. Currently, there is no scientific literature that focuses on improving this task. However, the emergence of new technologies from different fields may streamline the geometric data gathering with the modelling task and greatly improve both accuracy and workload. This study focuses on the revision of geometry measurement techniques, based on the application and quantification of the benefits and barriers that these techniques represent for their use in the building simulation and labelling. The techniques tested were Hololens, handheld laser scanner and handheld laser distance measurer. The evaluation considers time, cost and accuracy as well the tasks related to the post process of the data in BIM, which is not mandatory for building simulation, but it provided multiple benefits.
Permalink: https://doi.org/10.1088/1755-1315/410/1/012032

Abstract: The Energy Performance of Building Directive (EPBD) have asked to Member States (MSs) to include an Energy Performance Certificate (EPC) every time a dwelling is sold, rented or built. Additionally, the EPC must include a report that contains a list of recommended measures for improving their energy performance in a cost-effective way. Considering that the Directive does not directly mandate investments or any increase in renovation activity, building owners remain the single decision-makers to invest or not. Due to this, the recommendation list of measure is one of the main tools that can actually encourage building owners to perform renovation activities, avoiding the implementation of sub-optimal investments and preventing lost opportunities. The latest update of the directive, introduced in June 2018, has its main purpose to support and further reinforce the renovation of existing buildings. Despite this, the recommendation reports have not been modified and the latest evaluation of the directive states that it is not performing as expected. Little information can be found about it, either in the academic or institutional level. The article aims to provide a better understanding of the barriers that the energy recommendations report faces in its current state and proposing measures that can be uses to overcome these issues.
Permalink: https://doi.org/10.1088/1755-1315/410/1/012080