A framework for comfort assessment in buildings and districts retrofit process

The retrofit design of buildings and districts cannot exclude the occupants’ perspective if comfortable and healthy conditions have to be obtained. For this reason, the NewTREND1 project developed a collaborative platform for the energy efficient buildings and districts retrofit that includes the users’ perspective. Three modules have been developed for thermal comfort, acoustic comfort and behavioural assessment. These modules are integrated into a Simulation and Design Hub that, after gathering data from on-site measurements, builds a simulation model of the district, calculates yearly results and exposes them to the design team through a dedicated District Information Model server and user interfaces. These modules perform deep investigations on the occupants’ sensation and behaviour, based on both measured and simulated datasets and provide comparisons of comfort performances, considering different retrofit scenarios and related uncertainties. In details, the thermal comfort module performs analysis according to both predictive and adaptive models, evaluates the variability around the design conditions together with sensitivity analysis that highlights which parameters are the most critical for the retrofit design. The acoustic module provides a complete tool to predict and assess the indoor acoustic comfort, taking into account the performance of building envelope and the impact of district noise. Finally, the behavioural module empowers the building energy simulation with co-simulation capabilities that reproduces the real occupants’ behaviours in relation to comfort conditions. The final goal of the framework is to support the decision-making process in selecting the optimal retrofit option that achieves the targeted energy efficiency without infringing the occupant’s expectation in terms of comfort and well-being

Measuring Occupants' Behaviour for Buildings' Dynamic Cosimulation

Measuring and identifying human behaviours are key aspects to support the simulation processes that have a significant role in buildings' (and cities') design and management. In fact, layout assessments and control strategies are deeply influenced by the prediction of building performance. However, the missing inclusion of the human component within the building-related processes leads to large discrepancies between actual and simulated outcomes. This paper presents a methodology for measuring specific human behaviours in buildings and developing human-in-the-loop design applied to retrofit and renovation interventions. The framework concerns the detailed building monitoring and the development of stochastic and data-driven behavioural models and their coupling within energy simulation software using a cosimulation approach. The methodology has been applied to a real case study to illustrate its applicability. A one-year monitoring has been carried out through a dedicated sensor network for the data recording and to identify the triggers of users' actions. Then, two stochastic behavioural models (i.e., one for predicting light switching and one for window opening) have been developed (using the measured data) and coupled within the IESVE simulation software. A simplified energy model of the case study has been created to test the behavioural approach. The outcomes highlight that the behavioural approach provides more accurate results than a standard one when compared to real profiles. The adoption of behavioural profiles leads to a reduction of the discrepancy with respect to real profiles up to 58% and 26% when simulating light switching and ventilation, respectively, in comparison to standard profiles. Using data-driven techniques to include the human component in the simulation processes would lead to better predictions both in terms of energy use and occupants' comfort sensations. These aspects can be also included in building control processes (e.g., building management systems) to enhance the environmental and system management

Modelling window status in school classrooms. Results from a case study in Italy

In free running buildings users restore their thermal comfort usually opening and closing windows. In school buildings the window use is also useful to achieve good IAQ and avoid health hazards among students and teachers. In last decades many surveys focused on this topic, in order to understand which environmental parameters are the main triggers for users' actions. This paper investigates the relationship between window use and environmental stimuli in an Italian classroom. The survey concerned the monitoring of indoor and outdoor environmental variables and occupants' actions on windows to assess if occupants were influenced by the environment and the daily routine. Linear and logistic regression analyses were carried out to evaluate the relationship between variables and actions. The results highlight that indoor and outdoor temperatures are the main action trigger, while the relationship with CO2 concentration is weak. Also the daily routine affected students' actions, in fact the opening frequency is higher during breaks. Findings from previous studies are confirmed and new insight on behavioral pattern for school classrooms are presented

A literature review on driving factors and contextual events influencing occupants' behaviours in buildings

The present paper illustrates the results of a literature review on occupants' behaviours, assessing the actions' drivers. There is no general agreement about the reasons people interact with building systems or the driving factors that trigger their decisions. Even if lot of researchers focus on this target, they usually analyse one or two actions, while no survey makes a comprehensive investigation. Windows, lights, blinds, air-conditioning, thermostat, fans and doors patterns are investigated in different building uses (offices, houses and schools). The analysis is split in three parts: 1) evaluating the influence of environmental parameters 2) and time-related events (e.g. arrivals and departures) and 3) describing the variables adopted in behavioural models. The results suggest that not only environmental factors play a key role in the use of building systems but also contextual factors, as well as routine and habits, largely affect occupants' behaviours. Behavioural models are becoming more and more complex and comprehensive to better reproduce the human component. Considering the principal driving factors inside the behavioural models would bring a double benefit: improving the results of building simulation programs and assisting designers during the project of energy-saving and comfortable building

Comfort e qualità dell’aria per le nuove scuole smart: un innovativo sistema di apertura automatizzata delle finestre

Le aule scolastiche sono un ambiente estremamente delicato sia perché rappresentano il secondo posto, dopo le mura domestiche, dove bambini e ragazzi trascorrono maggior tempo, sia per l’elevata densità di occupazione nelle aule. L’edificio scolastico dovrebbe disporre di ambienti salubri, che favoriscano l’apprendimento e l’attenzione degli studenti, che riducano al minimo la proliferazione di batteri e, di conseguenza, l’assenteismo. Fattori ambientali di disturbo, come elevate temperature e scarso ricambio d’aria, possono determinare un calo di attenzione e quindi una riduzione nel rendimento. Al contrario, se le persone lavorano in un adeguato contesto psico-fisico, l’efficienza, la produttività e il livello di benessere aumentano. Negli edifici di nuova costruzione e nelle ristrutturazioni questa problematica è ulteriormente enfatizzata dall’utilizzo di involucri superisolati e serramenti a elevata tenuta all’aria. Da un punto di vista prettamente ambientale, il problema della salubrità nelle aule può essere lenito mantenendo un adeguato livello di qualità dell’aria e di comfort termico. Questo obiettivo è stato raggiunto con l’ausilio di un sistema meccanico automatizzato che ha il compito di gestire le aperture e le chiusure delle finestre secondo un opportuno algoritmo di controllo basato sul modello di comfort adattivo. Il sistema fornisce i risultati migliori quando viene affiancato ad una progettazione intelligente delle aperture vetrate, sia a livello di posizione che di tipologia: è preferibile la collocazione delle finestre sul medesimo lato, per evitare fastidiose correnti, e l’unione del sistema ad anta con sovrapposta apertura a vasistas

Comparing real and predicted window use in offices. A POE-based assessment

Accurate predictions of human-building interactions are essential to decrease energy waste and improve indoor comfort. Although users’ dynamic behaviour has been recognised, most of simulation programs still work using deterministic rules. This paper investigates the effectiveness of both deterministic and stochastic models in reproducing window openings, using a Post- Occupancy evaluation (POE). A summer monitoring campaign in offices settled in Mediterranean climate was performed to acquire experimental data. Results highlight that deterministic approaches poorly reflect real behaviours. Probabilistic models seem to represent effective users’ actions. Findings demonstrate the urgent need of behavioural approaches in simulations

Indoor air quality and thermal comfort optimization in classrooms developing an automatic system for windows opening and closing

Thermal comfort and indoor air quality in school classrooms are essential requirements to promotestudents’ productivity and reduce health symptoms. This paper presents the development of an automaticsystem for window openings, based on thermal comfort and indoor air quality correlations. The researchwas carried out in two adjacent classrooms. The initial phase aimed at assessing environmental conditionsin classrooms, testing objective and subjective comfort models and establishing trigger parameters forwindow opening events; the second phase regarded the implementation of an adaptive control algorithmin an automatic system piloting windows with the aim of maintaining a satisfactory environment bothin terms of IAQ and thermal comfort. The main results show that: (1) the IAQ is a relevant issue in schoolclassrooms, because students usually suffer high CO2levels; (2) the stronger driving force for undertakingadaptive actions is thermal comfort, while the need to improve the air quality is a secondary constraint;(3) the mechanized system ensures a good quality in terms of IAQ, thermal comfort and users’ satisfaction