bluuebunny/crossref_metadata_2025 huggingface dataset:
Condensation performance of superhydrophobic aluminium surface material used for cooled ceiling panels under highly humid indoor conditions
Authors: Zhong Z W , Niu J L , Ma W , Yao S H , Yang M , Wang Z K
Published: December 2021

The application of radiant cooling systems is very limited in hot and humid areas due to condensation. Research on superhydrophobic surface (SHS) materials has shown the potential of restricting the size of condensate drops on these materials, which provides possibilities for preventing dripping and thereby alleviating condensation risks for cooled ceiling panels, but there are few studies on the anti-condensation performance of these materials under the scale and conditions of building applications. An experimental study of condensation on superhydrophobic materials under indoor conditions is presented in this article. Two material samples with a size of 2.5 cm, including a superhydrophobic aluminum sheet and a pure aluminium sheet, were affixed on a cooled ceiling panel to perform the experiment under the following condition: temperature is 25°C ± 0.5°C, relative humidity is 80% ± 5%, and air dew point is 21.4°C. The panel was cooled by chilled water of 6°C for eight hours. The measured temperature on sample surfaces was about 13.5°C during the experiment. After eight-hour condensation, the diameter of drops on the superhydrophobic aluminum sheet was less than 150 μm, while the max drop on the pure aluminum sheet was near 4 mm. The results suggested that the size of condensate drops on superhydrophobic surface materials can be largely restricted during a long-time indoor operation below the dew point, which shows their potential for constructing condensation-free radiant cooling panels.
Passive evaporative cooling through water-filled bricks: a preliminary investigation
Authors: Tejero-González A , Nocera F , Costanzo V , Velasco-Gómez E
Published: December 2021

Direct evaporative cooling is widely known to be an energy efficient air-conditioning option for arid and semi-arid climates. However, care must be taken on humidity ranges achieved indoors. Existing literature presents several options for integrating evaporative cooling within buildings for passive cooling applications. This work aims at expanding the current knowledge by focusing on the use of water-filled hollow bricks to implement evaporative cooling of air in contact with the brick’s surfaces. A prototype is built and experimentally characterized under controlled air velocity, air temperature and relative humidity conditions. Results on the psychrometric conditions achieved under different geometric arrangements (i.e., with one, two or three rows of four bricks each) are presented and discussed. Insights on likely building integration of the system for passive cooling purposes in farms and agriculture applications are eventually given.
Towards multifunctional building elements: thermal activation of a composite interior GFRP slab
Authors: Khovalyg D , Mudry A , Pugin M , Keller T
Published: December 2021

Modular multifunctional building elements can overcome major disadvantages of the traditional sequential design and become prospective design solutions for sustainable construction. Thus, this work explores lightweight glass fiber-reinforced polymer (GFRP) profiles capabilities as multifunctional load-bearing slab modules in buildings. By adding water channels in a cellular structure of pultruded GFRP elements, hydronic radiant thermal conditioning of the indoor space can be enabled. Additionally, the water channels can protect critical slabs in case of a fire. A preliminary design of a multifunctional GFRP slab is performed for an office case study building by modifying a commercial slab profile with triangular channels. The thermal design load of the slab unit is determined using Rhino 6, and heat conduction and convective heat transfer for ceiling cooling and floor heating/cooling cases are investigated using ANSYS Fluent. The results show that a commercial GFRP profile can be modified to accommodate water channels and provide adequate heating and cooling at the upper or lower face. In addition, Serviceability Limit State is verified and required water flow adjustment in case of a fire outbreak scenario is discussed. Thus, the GFRP radiant slab has the potential as a pre-fabricated alternative for traditional embedded radiant systems.
In-situ performance evaluation of historic box-type windows with vacuum glazing
Authors: Schuss Matthias , Pont Ulrich , Wölzl Magdalena , Schober Peter , Mahdavi Ardeshir
Published: December 2021

Climate protection objectives and energy efficiency targets imply stricter performance expectations from both new and retrofit building projects. Given the related important role of the building envelope, there is a need for a holistic approach to the design, construction, as well as laboratory and field testing of buildings’ window and wall systems. In this context, the present contribution reports on recent efforts regarding the thermal retrofit of box-type windows. In the course of an actual research project, vacuum insulated glass (VIG) elements were integrated with ten existing box-type windows at six locations in Austria. To facilitate empirical testing and evaluation of these windows, a detailed concept for a continuous in-situ performance monitoring concept was designed and implemented together with the required monitoring infrastructure. This infrastructure involves the deployment of regular state-of-the-art IoT (Internet of Things) technology and enables the continuous monitoring of the salient performance indicators (including temperature, relative humidity, and heat flow). The derived values of performance indicators (such as the fRsi-value) can facilitate, among other things, the assessment of water vapor surface condensation risk. Collected data since mid-2020 cover both hot and cold weather periods have been analysed to capture performance differences between alternative vacuum glass settings at the testing locations. The alternative implementations pertain to different positions of the glazing layer (inside versus outside), different opening directions of the casements, and different positions of box-type within the opaque wall. Moreover, for comparison purposes, monitoring equipment was integrated into a comparable regular box-type window (with float glass or insulation glass) at each of the demonstration sites. Occurrences of potential visible or functional defects (including surface condensation) have been documented as well. The paper presents, analyses, and discusses the preliminary findings of this effort in detail.
Comfort and efficiency-based improvements to the control of residential Venetian blinds
Authors: Roberts J , De Michele G , Pernigotto G , Gasparella A , Avesani S
Published: December 2021

This study focuses on the control of movable Venetian blinds. Multiple improvements to an existing on/off open-loop control strategy in a case-study apartment have been simulated in TRNSYS 18, thanks to the detailed optical and thermal modelling allowed by the Bidirectional Scattering Distribution Function (BSDF) used as input to the Type56_CFS. The control strategy improvements include the combination of rule-based, closed-loop and discrete state control, in addition to four control strategy activation methods (three use a schedule, and one measures the external temperature). Simulated control inputs include internal temperature, external temperature and vertical irradiance. The results show reductions in overheating, achieved without completely blocking natural illumination or compromising heating demand. While on/off control in winter often leads to increased heating energy consumption, the space sees regular overheating when on/off control is inactive over winter. Conversely, discrete state control is able to more precisely control solar gains in winter to maintain an adequate temperature without utilising the heating system, all the while allowing some level of natural illumination. Ultimately, it is concluded that the choice of the control strategy depends on which objective (minimisation of heating energy consumption, maximisation of daylight harvesting, reduction of overheating risk, etc.) is prioritised.
Innovative approaches to thermochromic materials for adaptive building envelopes
Authors: Pérez G , Serra V , Garshasbi S , Favoino F , Sirvent P , Shah K W , La Roche P , Galán I , Santamouris M
Published: December 2021

Thermochromic (TC) materials are characterized by a change of their optical response at a specific temperature. They can work based on both, the alteration of solar reflection by temperature, or the change of photoluminescence intensity. In building applications, this type of smart materials enhances the rejection of solar heat for high temperatures to favour cooling of the envelopes and reduces this rejection for low temperatures to improve surface heating. This adaptive optical response improves energy efficiency and reduces environmental impact of urban areas. Most of the current advances in this area are related to TC glazing based on Vanadium oxide, while opaque TC materials have been developed as based on Leuco dyes. The main drawback of these last materials is their significant aging in outdoor applications due to a photo-degradation process. The present work shows the recent results of a multidisciplinary and multinational consortium for research on innovative approaches to thermochromic materials for adaptive building envelopes. Next steps will be focused on building simulation to evaluate material choices across different performance aspects, while physical prototypes will be used for inter-laboratory evaluation of such performance and material durability.
Heat, Moisture and Airflow coupled Model for Historical Building
Authors: Zhao G L , Xie H R , xia C C , Hokoi S , Li Y H
Published: December 2021

The current building simulation of heat air and moisture (HAM) only regards the indoor air as homogeneous, which cannot accurately predict and evaluate the thermal and humid environment of complex historical buildings. In this study, the heat, moisture, and airflow coupled model (HAM-CFD model) was developed by FORTRAN programming, and then the simulation results of the HAM model and the HAM-CFD model were compared to study the characteristics of indoor environment under the action of airflow. The results show that there is a coupling effect between the indoor airflow and heat and moisture transfer of walls. The HAM-CFD model can reflect the temperature stability of the building center, and has a better correlation with rainfall. The HAM-CFD model can more truly reflect the changes of building temperature and moisture content in complex thermal and humid environment.
Optimizing occupant-centric building controls given stochastic occupant behaviour
Authors: zadeh Zeinab Khorasani , Ouf Mohamed M.
Published: December 2021

Occupant-centric control (OCC) strategies represent a novel approach for indoor climate control in which occupancy patterns and occupant preferences are embedded within control sequences. They aim to improve both occupant comfort and energy efficiency by learning and predicting occupant behaviour, then optimizing building operations accordingly. Previous studies estimate that OCC can increase energy savings by up to 60% while improving occupant comfort. However, their performance is subjected to several factors, including uncertainty due to occupant behaviour, OCC configurational settings, as well as building design parameters. To this end, testing OCCs and adjusting their configurational settings are critical to ensure optimal performance. Furthermore, identifying building design alternatives that can optimize such performance given different occupant preferences is an important step that cannot be investigated during field implementations of OCC due to logistical constraints. This paper presents a framework to optimize OCC performance in a simulation environment, which entails coupling synthetic occupant behaviour models with OCCs that learn their preferences. The genetic algorithm for optimization is then used to identify the configurational settings and design parameters that minimize energy consumption under three different occupant scenarios. To demonstrate the proposed framework, three OCCs were implemented in the building simulation program, EnergyPlus, and executed through a Python package, EPPY to optimize OCC configurational settings and design parameters. Results revealed significant improvement of OCC performance under the identified optimal configurational settings and design parameters for each of the investigated occupant scenarios. This approach would improve OCC performance in actual buildings and avoid discomfort issues that arise during the initial implementation phases.
Designing a 24-hour perturbation method for the estimation of a building heat transfer coefficient
Authors: Juricic S , Rouchier S , Goffart J
Published: December 2021

Verification of the actual thermal performance of a building envelope after renovation is likely to become a useful key for performance contracting in the frame of heavy retrofit operations in buildings. Some existing methods such as the co-heating method, use on-site measurements to estimate the Heat Transfer Coefficient, or its inverse the overall thermal resistance. Although reliable and accurate, they need several days to several weeks of undisturbed measurements which can be rather inconvenient for building occupants and quite expensive in terms of operational costs. This paper investigates perturbation methods to design a 24-h heat input signal that would ensure an accuracy similar to or better than other perturbation methods to estimate an overall thermal resistance of the building envelope. The paper first studies 256 different squared heating signals in a numerical methodology to determine common characteristics of high-scoring 24-h signals. An experimental campaign in a wooden-framed house tested one of the high-scoring signals. The experimental results showed estimation errors higher than expected but consistent with the literature.
Energy performance assessment of passive buildings in future climatic scenarios: the case of study of the childcare centre in Putignano (Bari, Italy)
Authors: Campagna L M , Carlucci F , Russo P , Fiorito F
Published: December 2021

The building sector is a primary target for GreenHouse Gas emissions mitigation efforts, as it accounts for 36% of final energy use. The most effective mitigation strategies include the energy retrofit of the existing building stock. Among existing buildings, particular attention should be paid to school buildings, which are among the most diffuse public buildings in Europe, most of them built decades ago, with a resulting high potential in terms of refurbishment effectiveness. Moreover, schools cover a social function and require high levels of indoor environmental quality. In this field, the research activity is intense, but retrofit strategies are still conceived considering historical weather data, which could not represent correctly present and future climate patterns, reducing the retrofit effectiveness. In this work, an energy retrofit to “Passivhaus standard” of a childcare centre located in the Mediterranean area is analysed through dynamic simulations. A post-retrofit building model is simulated using Typical Meteorological Year (TMY) and compared with the ones simulated in future weather scenarios, created using the morphing method. The analyses aim to assess if the technical solutions currently adopted on the basis of the TMY will lead to acceptable energy performance in future decades. Furthermore, a sensitivity analysis of different design solutions is performed, aiming to assess their effectiveness in future weather conditions.
Towards net-zero carbon performance: using demand side management and a low carbon grid to reduce operational carbon emissions in a UK public office
Authors: Burman E , Jain N , de-Borja-Torrejón M
Published: December 2021

This paper investigates the performance of an office building that has achieved a low carbon performance in practice thanks to a performance contract and Soft Landings approach. The findings show the potential of this building for further de-carbonisation as a result of electrification of heating and load shifting to take advantage of a low carbon electricity grid. Whilst retrospective modelling based on the past carbon intensity data shows the effectiveness of demand-side management, assessment of the existing smart readiness of the building revealed that the building services and control strategy are not fully equipped with the data analytics and carbon or price signal responsiveness required to facilitate grid integration. The environmental strategy and procurement method used for this building combined with an effective grid integration strategy can serve as a prototype for low carbon design to achieve the ever stringent carbon emissions objectives set out for the non-domestic buildings.
Demand Side Flexibility Potential and Comfort Performance of Non-Residential Buildings
Authors: Chantzis Georgios , Antoniadou Panagiota , Symeonidou Maria , Giama Effrosyni , Oxizidis Simeon , Kolokotsa Dionysia , Papadopoulos Agis M.
Published: December 2021

The need to create and maintain a sustainable indoor environment is now more than ever compelling. Both the legislation framework concerning the energy performance of buildings, as determined in its evolution through the EU Directives 2010/31/EU, 2012/27/EU and 2018/844/EU, and the European strategic plans towards green buildings, denote the need of sustainability and comfort of indoor environment for the occupant. Moreover, the EU Directive 2018/2001 sets the renewable energy target of at least 32% for 2030, denoting that the high renewable energy sources penetration level leads to challenges in the design and control of power generation, transmission and distribution. Demand side management may be able to provide buildings with the energy flexibility needed, in order to utilize the intermittent production of Renewable Energy Sources in a much more efficient and cost-effective way. The flexibility potential of installed building systems is investigated, while considering the effects on the indoor environment conditions and the perceived comfort. The implemented Demand Response (DR) control strategy shifts loads by changing heating system set point temperatures, based on market clearing prices of the day ahead market. The results indicated a reduction in energy consumption and energy costs, while maintaining indoor environment quality at satisfactory levels.
Thermal transmittance prediction based on the application of artificial neural networks on heat flux method results
Authors: Gumbarević S. , Milovanović B. , Gaai M. , Bagarić M.
Published: December 2021

Deep energy renovation of building stock came more into focus in the European Union due to energy efficiency related directives. Many buildings that must undergo deep energy renovation are old and may lack design/renovation documentation, or possible degradation of materials might have occurred in building elements over time. Thermal transmittance (i.e. U-value) is one of the most important parameters for determining the transmission heat losses through building envelope elements. It depends on the thickness and thermal properties of all the materials that form a building element. In-situ U-value can be determined by ISO 9869-1 standard (Heat Flux Method - HFM). Still, measurement duration is one of the reasons why HFM is not widely used in field testing before the renovation design process commences. This paper analyzes the possibility of reducing the measurement time by conducting parallel measurements with one heat-flux sensor. This parallelization could be achieved by applying a specific class of the Artificial Neural Network (ANN) on HFM results to predict unknown heat flux based on collected interior and exterior air temperatures. After the satisfying prediction is achieved, HFM sensor can be relocated to another measuring location. Paper shows a comparison of four ANN cases applied to HFM results for a measurement held on one multi-layer wall – multilayer perceptron with three neurons in one hidden layer, long short-term memory with 100 units, gated recurrent unit with 100 units and combination of 50 long short-term memory units and 50 gated recurrent units. The analysis gave promising results in term of predicting the heat flux rate based on the two input temperatures. Additional analysis on another wall showed possible limitations of the method that serves as a direction for further research on this topic.
Utilizing High Performance Computing to Improve the Application of Machine Learning for Time-Efficient Prediction of Buildings’ Daylighting Performance
Authors: Labib Rania
Published: December 2021

Architects often investigate the daylighting performance of hundreds of design solutions and configurations to ensure an energy-efficient solution for their designs. To shorten the time required for daylighting simulations, architects usually reduce the number of variables or parameters of the building and facade design. This practice usually results in the elimination of design variables that could contribute to an energy-optimized design configuration. Therefore, recent research has focused on incorporating machine learning algorithms that require the execution of only a relatively small subset of the simulations to predict the daylighting and energy performance of buildings. Although machine learning has been shown to be accurate, it still becomes a time-consuming process due to the time required to execute a set of simulations to be used as training and validation data. Furthermore, to save time, designers often decide to use a small simulation subset, which leads to a poorly designed machine learning algorithm that produces inaccurate results. Therefore, this study aims to introduce an automated framework that utilizes high performance computing (HPC) to execute the simulations necessary for the machine learning algorithm while saving time and effort. High performance computing facilitates the execution of thousands of tasks simultaneously for a time-efficient simulation process, therefore allowing designers to increase the size of the simulation’s subset. Pairing high performance computing with machine learning allows for accurate and nearly instantaneous building performance predictions.
Simplified Model for Analyzing Shortwave Solar Effects on Indoor Thermal Comfort
Authors: Wang Nan , Wang Julian
Published: December 2021

Shortwave solar irradiance through building windows may have significant impacts on indoor thermal comfort, especially in near-window zones. Such effects change with intensity and spectral variations of the solar irradiance incident on building windows, which is related to the day of the year, time of day, orientation and dimension of the window, and atmospheric conditions. To assess the effects on thermal comfort, we derived a variable - mean radiant temperature delta based on a proposed spectrally-resolved method to represent the quantity of shortwave solar irradiance incident on occupants and be incorporated into PMV (predicted mean votes)-based thermal comfort models. By characterizing the variations of the calculated PMV values under different solar conditions, the influencing factors to indoor thermal comfort by shortwave solar irradiance were obtained and analyzed. Last, upon a series of parametric settings and numerical analysis, simplified statistical regression models were also established to directly predict spectrally-resolved mean radiant temperature delta and PMV values. This could be convenient and extensively to estimate the solar effects on indoor thermal comfort within the near-window zones.
On the Low Frequency Impact Noise Measurement in Residential Buildings
Authors: Urbán D , Zat’ko P
Published: December 2021

We commonly encounter cases that, despite the fact that buildings meet normative requirements, people are disturbed by unwanted noise generated by walking and other sources of impact noise. It is not unusual that in practice the designer often moves on the edge of the required criteria in order to reduce the cost of constructions and its parts. In this article, we selected 4 blindly chosen cases of flats where complaints from residents about high levels of impact noise were recorded although the construction meets the requirements set out in the standard. Based on the obtained documentation of in-situ performed measurements by different consulting companies, BEM and FEM models were created, and the distribution of acoustic pressure in an enclosed space and compared different methods of spatial averaging of the resulting acoustic pressure were simulated. The aim of this analysis is to point some of the reasons for possible user complaints about the impact noise despite normative requirements. The usual problems are benevolent national requirements and the issue of measuring noise in the low frequency range and underestimating its significance. The article also discusses the currently set requirements for the evaluation of floor structures in selected countries.
An OpenBIM workflow to support collaboration between Acoustic Engineers and Architects
Authors: McGinley Tim Pat , Vestergaard Thomas , Jeong Cheol-Ho , Pind Finnur
Published: December 2021

Architects require the insight of acoustic engineers to understand how to improve and/or optimize the acoustic performance of their buildings. Normally this is supported by the architect providing digital models of the design to the acoustic engineer for analysis in the acoustician’s disciplinary software, for instance Odeon. This current workflow suffers from the following challenges: (1) architects typically require feedback on architectural disciplinary models that have too much geometric information unnecessarily complicating the acoustic analysis process; (2) the acoustician then has to waste time simplifying that geometry, (3) finally, this extra work wastes money which could otherwise be spent on faster design iterations supported by frequent feedback between architects and acousticians early in the design process. This paper focuses on the architect / acoustician workflow, however similar challenges can be found in other disciplines. OpenBIM workflows provide opportunities to increase the standardization of processes and interfaces between disciplines by reducing the reliance on the proprietary discipline specific file formats and tools. This paper lays the foundation for an OpenBIM workflow to enable the acoustic engineer to provide near real time feedback on the acoustic performance of the architectural design. The proposed workflow investigates the use of the international standard IFC as a design format rather than simply an exchange format. The workflow is presented here with the intention that this will be further explored and developed by other researchers, architects and acousticians.
Too Hot to Stay at Home: Residential Heat Vulnerability in Urban India
Authors: Agarwal Aditi , Samuelson Holly
Published: December 2021

Rising temperatures may lead to deadly heat waves in India. Combined with a growing urban population and mass production of affordable housing, this can sharply accelerate the demand for space cooling. India’s voluntary Energy Conservation Building Code - Residential (ECBC-R) or Eco Niwas Samhita 2018 limits thermal transmittance of the envelope. This research considers and critiques this approach through building simulation and an analysis of indoor comfort and severity of overheating during the summer months (April-May-June), in hot-dry and warm-humid climate zones. Code requirements neither vary with climate zones, nor is it adapted to future climate conditions. Our building simulations and analysis show that soon (2030s) parts of the country are likely to suffer from overheating 74% of time in summer. A minimally code compliant building would need air conditioning 90% of summer while a highly efficient iteration could reduce this by a third, in the hot-dry climate zone. Further, commonly used envelope assemblies are uncomfortably hot 77% (in the hot-dry zone) and 23% (in the hot-humid zone) of time in summer, on average. This analysis illustrates the vulnerability of current construction techniques to extreme heat and aims to avoid a long-term lock-in of inefficient, high energy consuming residential buildings.
A field study on summertime overheating of six schools in Montreal Canada
Authors: Xie Zihan , Shu Chang , Reich Ben Zegen , Wang Lin , Baril Daniel , Ji Lili , Yang Senwen , Bai Xuechen , Zmeureanu Radu , Lacasse Michael , Wang Liangzhu , Ge Hua
Published: December 2021

Due to global climate change, the world has been experiencing significant increases in average temperatures and the frequency and intensity of extreme weather events such as heatwaves. The overheating problem in indoor spaces of buildings has become a concern to the comfort and health of building occupants, especially vulnerable populations such as the elderly, children, or the sick. A field monitoring network consisting of rooftop weather stations and indoor sensors has been set up on 11 buildings of different types in Montreal, Canada. This paper presents the results of field measurements of indoor thermal conditions of six school buildings to assess the risks of summertime overheating. These six primary school buildings were built in 1930-1966 with window-wall-ratios between 10-30% and limited mechanical ventilation. The indoor dry-bulb air temperature, relative humidity, and CO2 concentrations are measured by indoor wireless sensors. The weather conditions, including dry-bulb temperature, relative humidity, solar radiation, rainfall, wind speed, and wind direction, are measured by rooftop weather stations. Measurements presented in this paper are collected from July to September 2020, which include four different time intervals: (a) during two heatwaves, (b) during summer break when schools were closed, and (c) when schools were reopened, and windows were intermittently opened. Data analysis shows that the indoor and outdoor temperature difference has a strong linear correlation with the outdoor temperature observed for all school buildings. This correlation is also affected by building operations, such as opening windows, closing blinds, and the micro-climate of their surroundings.
Relaxing and working from home: associations between heating, ventilation and cooling system typologies and indoor soundscape evaluation
Authors: Torresin Simone , Albatici Rossano , Aletta Francesco , Babich Francesco , Oberman Tin , Stawinoga Agnieszka Elzbieta , Kang Jian
Published: December 2021

Data from an online survey conducted in January 2021 by 464 participants living in London and working from home (WFH) after the COVID-19 outbreak were analysed, focusing on: (1) types of building services at home, (2) perceived sound dominance of building services, and (3) the perception of the indoor acoustic environment (i.e. the indoor soundscape) in relation to two main activities, i.e. WFH and relaxation. Results show that most of participants’ houses had radiators for heating and relied on window opening for ventilation and cooling. Air systems (e.g., HVAC systems) resulted in higher perceived dominance compared to other systems, but only when evaluated for WFH. Sound dominance from building services was in turn related to soundscape evaluation. Spaces with less dominant sounds from building services were more appropriate for both WFH and relaxation, and spaces with fewer dominant sounds were assessed better, but just for WFH. Participants’ evaluations generally did not differ according to building service typology. The presence of air-cooling systems was associated with better perceived sound environments, most likely due to better acoustics conditions in newly built or retrofitted dwellings, more probably equipped with air cooling systems. Preliminary findings point out the importance of carefully considering the dominance of sounds by building services, especially for air systems, in relation to traditional and new uses of residential buildings.
Comfortable and safe environments for people with autism: preliminary analysis of risks and definition of priorities in the design phase
Authors: Zaniboni L , Marzi A , Caniato M , Gasparella A
Published: December 2021

People with autism deserve specific attention as concern environmental comfort, well-being and accessibility of environments, not only because they are a significant and growing share of the total population, but also because they can show special sensitiveness to the variation and value of several environmental parameters. In this work, the main building-related critical issues connected to the special environmental sensitivity in the autism spectrum condition are highlighted and analysed. By means of a questionnaires’ survey among parents and caregivers of people with autism, their sensitivity to different thermal, visual, acoustic and indoor air quality stimuli was evaluated. Then, a list of risk factors was prepared for a residential context, classifying them into environmental risks, leading to discomfort and dangerous response for people with autism; and accidental risks, deriving from unpredictable events, even more dangerous for people with special perceptual disorders. According to the outcomes of the survey and based on literature considerations, probability and severity of environmental and accidental risks were estimated on a scale from 1 to 5 in the different rooms of residential buildings. This permitted to draw up a hypothetical system of possible interventions and solutions to be considered during the design phase, establishing a different priority in the different rooms of a dwelling, in order to increase the occupant’s comfort, safety and autonomy, and improving physical and psychological well-being.
Numerical Assessment of Seven Ventilation Systems for Social Residential Buildings based on Indoor Air Quality and Energy Consumption
Authors: Sérafin Guillaume , Abadie Marc O. , Joubert Patrice
Published: December 2021

This work presents a modelling approach for evaluating ventilation systems for their ability to provide good indoor air quality in dwellings. Infiltration and ventilation rates are defined by the conventional French 3CL-DPE standard. The case study is a two-bedroom apartment with a shared or separate kitchen and living room. Three natural ventilation options and four mechanical ventilation systems are compared with respect to exposure to PM2.5, NO2 and formaldehyde. Pollutant concentration levels are assessed in each room based on a scenario of daily occupancy, average annual outdoor concentrations and internal sources. The daily exposure of the occupants to the targeted substances allows the comparison of ventilation systems on the basis of the ULR-QAI index developed at LaSIE laboratory from La Rochelle University. For this case study, it results that controlled mechanical systems are much more efficient than natural ventilation systems, especially in the case of an open-plan kitchen.
Development of a Natural Soil Depressurization System Sizing Tool
Authors: Abadie Marc , Romani Zaid , Burlot Michel , Nicolle Jérôme , Peigné Pierre , Druette Lionel , Collignan Bernard , Allard Francis
Published: December 2021

This paper presents a summary of the main developments and results achieved in the frame-work of the French research project called EVAL-SDS. This project aims to analyse the performance of Natural, i.e. without use of fan for extraction, Soil Depressurization Systems (NSDS) to protect the built indoor environment from soil gaseous pollutant (Radon, Volatile Organic Compounds…). In this paper, the aeraulic performance of NSDS is studied i.e. its capacity to extract air from the ground to protect building’s occupants. To this end, we first performed measurements of airflow rates extracted by a NSDS integrated in a test-house during one year. Those data include various weather conditions (stack effect, wind) for several key parameters (wind extractor type, slab air permeability and basement pressure). Then, a dedicated calculation tool has been developed and validated against the experimental results. This numerical model has been used to evaluate the NSDS performance in France for different building heights and ventilation systems. The results show that NSDS succeed in creating a negative pressure under the building slab most of the time and that the extracted airflow rates can be enhanced by better design of wind extractor, association with mechanical insufflating ventilation system and thermal transfer from the building during the heating season.
Modelling mean radiant temperature in outdoor environments: contrasting the approaches of different simulation tools
Authors: Badino E , Ferrara M , Shtrepi L , Fabrizio E , Astolfi A , Serra V
Published: December 2021

Global warming and increasing urbanization are expected to threaten public health in cities, by increasing the heat stress perceived by the inhabitants. Outdoor thermal comfort conditions are influenced by the material and the geometric features of the surrounding urban fabric at both the urban and building scales. In built environments, performance-aware design choices related to street paving or building façade can enhance outdoor thermal comfort in their surroundings. Reliable estimations of outdoor thermal comfort conditions are required to evaluate and control the micro-bioclimatic influences of different design choices. The mean radiant temperature is the physical variable that has the greatest influence on outdoor thermal comfort conditions during summertime. Since its calculation is complex, the available simulation tools employ different approaches and assumptions to estimate it, and potential users need to be aware of their capabilities and simplifications. This research compares the calculation procedures and assumptions of different performance simulation tools (i.e. ENVI-met, TRNSYS, Ladybug/Honeybee, CitySim, and SOLENE-microclimat) to predict the mean radiant temperature in outdoor spaces, based on the available information in the scientific literature. Their ability to account for different radiative components in both the longwave and shortwave spectra is summarized, and practical information regarding the degree of interoperability with the modelling environments and the level of geometrical detail of the virtual model supported by the tools is provided. This work aims to help potential users in the selection of the most appropriate performance tool, based on the requirement of their projects.
The hygrothermal assessment of cement-ash-based mortar
Authors: Krejcirikova Barbora , Rode Carsten , Wargocki Pawel , Kolarik Jakub , Peuhkuri Ruut
Published: December 2021

Cement is the second most consumed substance by weight in the world, after water. The growing demand for reduced emissions of CO2 urges the cement industry to find materials with a low CO2 footprint, which calls for cement substitution. An assumption of the study has been that sewage sludge ash (SSA), an industrial by-product, can be applied as a potential cement substitute in cement-based materials without compromising material performance. The study investigated the effect of partial replacement of cement by SSA in mortar on hygrothermal properties of mortar. Two sewage sludge ashes originated from wastewater treatment plants located in the Greater Copenhagen area, Denmark. SSAs consisted of larger particles compared to cement particles; thus cement-ash-based mortar resulted in more porous structures compared to cement-based mortar. The higher porosity was responsible for a decrease of the thermal conductivity of the mortar. Significant differences were recognized in sorption isotherms of individual components, i.e. cement and ashes. However, their effect on the sorption isotherms of the mortars was minor.
Development of advanced multifunctional façade systems: Thermo-acoustic modelling and performance
Authors: Fantucci Stefano , Favoino Fabio , Fenoglio Elisa , Serra Valentina , Perino Marco , Shtrepi Louena , Bivanti Marta , Astolfi Arianna
Published: December 2021

The development of lightweight and multifunctional curtain wall systems, which integrate different technological solutions, is aimed at achieving increasingly higher requirements related to energy efficiency as well as indoor environmental quality in non-residential buildings. On one hand lightweight and thin façade elements present several advantages (such as construction time, space, and transportation savings, less weight on primary structure etc.), while facing the challenge of guaranteeing the required thermal and acoustic performance and achieving legislative compliance on the other. In the framework of the Horizon 2020 Project Powerskin+ a new concept of multifunctional façade, which combines high performance insulation, energy harvesting, heating system, and latent heat storage capabilities is under development. Within the design process of the different sub-modules (opaque and transparent), performance calculations are carried out by means of existing simulation tools, or ad-hoc developed models for more complex systems. In this study, the authors present the main steps required to accelerate the simulation-based design process and the future thermal and acoustic optimization of the novel lightweight and multifunctional façade element.
Trent Brick Panel: innovative envelope system designed according latest UK national fire and energy performance regulations
Authors: Calabrò E , Peron F , Meggers F J
Published: December 2021

In November 2018, following the Grenfell Tower tragedy in London, the Ministry of Housing, Communities & Local Government (MHCLG) introduced an amendment to the Building Regulations 2010, which outlined stricter rules banning the use of combustible materials defined by the new Building Regulation 7(2). This change had a significant impact since early 2019, on the materials and systems that can be used in the construction sector. In 2020, the global pandemic caused by the diffusion of the COVID-19 virus represented a new challenge for the industry, with implications on programme certainty, material procurement, workforce management, moving towards offsite manufacture. The development of the Trent Brick Panel is set against this historical and social context. The envelope prototype is the opportunity for innovation that follows the turn of events. The offsite manufacturing of glass-reinforced concrete panel, mimicking several finishes, is the result of a design investigation carried out with the market-leading actors: developers, main contractors, subcontractors, engineering consultancies, architects, local authorities and warranty providers. The research aims to give an overview of the design principles, sequence and buildability study, assessed weathering performance according to CWCT Sequence B test and fire performance.
The use of an internal airtight membrane in CLT external wall in terms of hygrothermal performance
Authors: Kukk V. , Kers J. , Kalamees T.
Published: December 2021

This study focused on the dry-out capacity of the vapor-permeable CLT (cross-laminated timber) external wall and the impact of using an internal airtight membrane. The results of the work were obtained first from the field measurements, after which the simulation model was created and validated, and the hygrothermal performance of the wall was analyzed by a stochastic approach. The results of this showed that the CLT dries out quickly and safely in a wall assembly with a high water vapor permeability, even with the large range of initial CLT MC (13-25%). When an additional airtight layer with high vapor diffusion resistance (Sd of 244 m) is added between the insulation and the CLT, the dry-out capacity of the CLT decreases significantly and there is a high probability of mold growth on the CLT surface. The risk of mold growth can be prevented when the vapor resistance (Sd) of the airtight layer is reduced to 1.5 m in a case where initial CLT MC is up to 25% and in a case where initial MC is up to 20%, the vapor resistance of an airtight layer must be reduced to 3 m.
Experimental study of hygrothermal conditions in a wooden room for numerical comparisons
Authors: Legros C , Piot A , Woloszyn M , Pailha M
Published: December 2021

The use of hygroscopic materials indoors has a significant impact on the hygrothermal balance of a room air. It affects both the temperature and the relative humidity. Numerical tools still lack of accuracy in predicting these parameters and some discrepancies are observed between their predictions and experimental measurements. It may be caused by the model itself or by incorrect inputs data (materials properties, occupancy schedule, ventilation rate, etc…) Therefore, an experimental study has been carried out at the room scale under real climate to obtain an experimental dataset as a basis for numerical comparisons. The hygrothermal parameters of the room air have been measured for different loads while all the inputs (heat and moisture generation, air exchange and materials properties) have been properly quantified. This article presents the experimental setup and some of the experimental data obtained.
Investigation of the transport properties for saline water in porous materials - Modeling of the permeability coefficient for saline water-
Authors: Sakai K , Takatori N , Ogura D , Wakiya S , Abuku M
Published: December 2021

Salt weathering is a major concern for cultural heritages such as ruins and tombs, and desalination by poulticing is an interesting potential method to efficiently remove contaminating salt. Predicting the degree of achievable desalination is very important. However, many existing models used to consider saline water transport in porous materials have been developed based on the theory of pure water. To understand saline water flow in porous materials, we determined the saline water permeability of a tuff stone by the falling-head method. We found that the permeability of the tuff stone was affected by factors other than the density and dynamic viscosity of the saline water.
What affects the performance of POD for the simulation of heat transfer through building component?
Authors: Hou Tianfeng , Roels Staf , Janssen Hans
Published: December 2021

The capability of the proper orthogonal decomposition for the simulation of heat transfer in building components is investigated via three applications: linear heat transfer (not coupled to mass transfer), mildly non-linear heat transfer (coupled to air and moisture transfer (hygroscopic)) and highly non-linear heat transfer (coupled to moisture transfer (capillary)). It is shown that increasing non-linearity leads to an increasing number of required construction modes. To further investigate the reason for this degrading performance of POD, the singular values’ decay progress from the different training snapshots is addressed in this paper. The results confirm that a fast decay of the singular values implies a high interrelation of the snapshots and a better performance of the POD method.
Community cooling infrastructure from waste heat among diverse building types in Rourkela Steel Township, India
Authors: Sen R , Teitelbaum E , Meggers F
Published: December 2021

Urban building energy modeling is an important field in the current decade due to the rising rate of urbanization, specifically in developing countries. The UN environment is promoting urban level space cooling approaches in the upcoming smart cities of India. Rourkela is a tier-2 steel township included within the ‘smart city’ mission in India and houses one of the largest Steel Plants of India, classified under Koppen Aw tropical climate zone. However it experiences extreme heat stress in the dry summer season before the onset of monsoons. The given study proposes an alternative cooling scenario utilizing waste heat from the rolling mill with which cooling in the range of 700-900 tons of nearly zero energy cooling can be made available in the surrounding areas, otherwise catered by an energy intensive cooling system reporting a COP of 2.45. This study can be further expanded to provide cooling to the nearby residential communities keeping the steel plant area as center point for community cooling infrastructure provision.