Building in Historical Areas: Identity Values and Energy Performance of Innovative Massive Stone Envelopes with Reference to Traditional Building Solutions

The intrinsic nature of local rocks shaped the features of built heritage in historical centers. The resulting building culture is part of the cultural heritage itself, and must be considered when building in such areas, while it is essential to solve the issues related to traditional constructions’ weaknesses. Nonetheless, the potentialities of massive stone envelopes, particularly the importance of thermal inertia, have contributed to redefining the language of contemporary architectural culture. Nowadays, although the trend of employing thin stone cladding panels is prevalent, thick stone envelopes are gaining a renewed importance. Previous literature demonstrated that mixed building technologies or massive stone envelopes coupled with load-bearing framed structures are able to meet comfort and safety requirements and to guarantee the integration of new constructions in the consolidated urban landscape, avoiding historicist approaches. This research, through the analysis of case studies, aims to describe innovative building solutions developed by contemporary architectural culture, comparing them with traditional stone masonry walls. Moreover, thermal energy performance of such building solutions is assessed through dynamic yearly simulations. Results show that these solutions are technically and architecturally suitable to build in historical centers, because they can express urban cultural identity and guarantee good energy performance and users’ comfort

Cool, translucent natural envelope. Thermal-optics characteristics experimental assessment and thermal-energy and day lighting analysis

Innovative construction elements are increasingly studied to improve the energy performance of new and existing buildings, to satisfy global regulations and societal needs. In this view, optimizing buildings energy efficiency and sustainability are crucial aspects, given their high energy saving potential with respect to the other sectors characterizing human activities. Natural materials are often preferred to artificial materials, thanks to their more sustainable production and to the reduced content of harmful substances. In particular, light, thin marbles have been recently analyzed as building envelope elements. Their cooling potential demonstrated how such envelopes have the threefold advantages of reducing solar heat gains into the building, accumulating and releasing less heat, reducing the Urban Heat Island (UHI) effect and consequently mitigating global warming. However, an important feature that has not yet been analyzed in literature and that is considered in this research is light passage throughout the translucent envelope, permitting an additional energy saving due to the contribution to artificial lighting. In this work, this feature of the translucent envelope is considered, by experimentally measuring thin, white marble panels’ optic characteristics and implementing them in a thermal-energy dynamic simulation, to demonstrate the additional advantage of natural daylight to the overall building energy balance

Smart cool mortar for passive cooling of historical and existing buildings: experimental analysis and dynamic simulation

In order to mitigate Urban Heat Island Effect and global warming, both governments and scientific community are working to reduce energy consumptions. In particular, the construction sector has a high potential in reducing energy demand, by means of both active and passive solutions. The European building stock is mainly composed by existing buildings as well as historical ones, which happens to be the less energy efficient ones. Moreover, retrofit operations are more complex on historical buildings, due to strict regulations for the preservation of such historical and cultural heritage. Considering this challenge, in this work we described and in lab analyzed possible passive solutions specifically designed for historical and existing buildings. In particular, we developed innovative cool colored mortars and tested them in lab, as well as investigated cool colored mortars, cool clay tiles and cool natural gravels performance when applied as envelope and roof elements, by means of dynamic simulation

Cool marble building envelopes. The effect of aging on energy performance and aesthetics

Marble envelopes represent a relatively common architectural solution used in variety of historic, modern and contemporary building facades. White marble envelopes have been shown to reduce solar heat gains, while improving indoor thermal comfort and energy efficiency in summer time. While marble is useful in this context, the urban atmosphere accelerates the degradation of marble elements. This leads to changes in optical characteristics, hence the aesthetics, and affects the energy efficiency benefits offered by white marble facades. These issues are investigated in order to predict the impact of degradation on energy performance and to the aesthetic value, such as change of color and luminosity. In this study, surface degradation of white marble is analyzed by means of accelerated weathering in the laboratory while examining changes to the optical characteristics of the materials. A dynamic simulation is carried out to assess the energy performance of a building as a case study

How subjective and non-physical parameters affect occupants’ environmental comfort perception

Employees’ wellbeing and comfort perception demonstrated to largely influence their productivity and tolerability of slight thermal discomfort conditions in the working spaces. Their whole comfort perception indeed depends on several parameters related to physical boundary conditions but also to the adaptation capability of occupants themselves and other personal, difficult to measure, variables. According to the available standards and regulations, only physical and measurable environmental parameters must be considered to evaluate occupants’ comfort conditions. Therefore, non-measurable factors such as socio-psychological, physiological, medical ones are currently not systematically considered. The present work aims to identify possible benefits in terms of occupants’ comfort perception due to non-physical strategies aimed at improving the work-environment quality and livability. To this aim, the environmental multi-physics and multi-domain performance of a mixed industry-office building is investigated through coupled in-field microclimate monitoring and questionnaires campaigns. The experimental microclimate monitoring and survey campaign were carried out to understand (i) the realistic indoor environmental conditions in terms of physical and measurable parameters and (ii) the personal perceptions and attitudes of the occupants with respect to those same ambient parameters, including also acoustic, lighting and medical investigation. Moreover, the collected experimental data were used to determine occupants’ comfort level through the classic comfort models, to be compared to the identified role of non-physical parameters on occupants’ final perception about the indoor environment. The main results show that non-measurable factors induced by virtuous company policy to improve employees’ working environment are effectively able to positively influence their whole-comfort perception even if the majority of workers do not have the opportunity to control their working environment. In fact, the consolidated comfort theories underestimate people satisfaction, as demonstrated by more than the 80% employees, who declared to be positively influenced by the pleasant aesthetics and livability of the workplace. The year-round experimental campaign demonstrated the need to further investigate the key role of non-physical parameters for possible incorporation into whole-comfort prediction models and standards. The role of such strategies could therefore be realistically considered as energy saving opportunities since they make building occupants much more open to tolerate slight uncomfortable conditions

Adapting towards resilience. Analysis of the construction features and dynamic energy performance of amphibious and floating houses

In the current scenario where urban areas are exposed to extreme climate phenomena, resilience of cities and buildings becomes fundamental. Thus, not only defensive, traditional actions, but also alternative solutions towards resilience need to be implemented. Amphibious and floating houses, still not investigated in literature, allow the building to adapt to water presence due to their specific construction and technical properties. Here, we consider such buildings’ typologies under the construction and thermal-energy performance lenses, by means of yearly dynamic energy simulations

Outdoor thermal and visual perception of natural cool materials for roof and urban paving

Given the acknowledged thermal performance of natural light color gravels applied as cool roof and cool urban paving, this work is aimed at investigating if such behavior is perceivable by pedestrians, who are questioned in this paper about their visual and thermal comfort perception. In fact, there are still related aspects to analyze, in order to optimize their application and provide a comfortable space for users, both on the thermal and the visual point of view. Therefore, the question that this work wants to answer is: given their intrinsic characteristics, do these materials create a sensitive thermally and visually more comfortable environment for pedestrians? In order to address this uninvestigated issue, users’ judgment about visual and thermal comfort of these surfaces is considered, also by comparing them with grassland and asphalt. Also, the statistical correspondence between physical properties of such materials and possible correspondence with respect to human perception with varying weather conditions is analyzed. Given the relatively high reflectance of these materials, it appears particularly important to evaluate these aspects, to consciously apply them as urban paving or roof covering by optimizing their natural passive cooling potential. In this preliminary study, users’ response to these surfaces is evaluated by mean of field surveys, both on the thermal and the visual evaluation, and contemporary in-field measurements of surface parameters. Also, human perception with respect to these high-reflectance surfaces’ is compared with the one related to grassland and asphalt, with varying weather conditions. Then, a statistical analysis is performed to investigate the differences among different gravels, grassland and asphalt, based on surveys’ results. The results show how pedestrians, questioned during summer days, prefer grassland, while asphalt is the less favorite surface both visually and thermally; there is a small difference between gravels’ types evaluation, while weather variability affect the preferences

Integrated Thermal-Energy Analysis of Innovative Translucent White Marble for Building Envelope Application

Marble is a natural material, used in the construction field since antiquity. It has always been used to communicate monumentality and solidity. Nowadays new technologies permit marble to express new languages: particularly, translucent marble technology overturns the concept of solidity. The main issue to address is the lack of thermal-energy performance of such a thin stone layer as the only facade component. Conversely, Bianco Carrara and Statuario marbles, for instance, have intrinsic benefits as natural cool materials, due to their high solar reflectance and thermal emissivity. Thus, this paper analyzes the thermal-energy and environmental behavior of marble facade for a new designed building in New York City. An integrated analysis of the energy performance of the marble skin is performed through a preliminary experimental characterization, carried out for two different types of naturally white marble, for comparative purposes. Then, a dynamic simulation model of the building is developed to evaluate year-round benefits and drawbacks of the translucent marble envelope in terms of indoor thermal comfort and air-conditioning requirement. The analysis showed how the proposed marble facade is able to decrease the energy requirement for cooling up to 6%, demonstrating possible relevant perspectives for marble-based facades, even in energy-efficient buildings

A sustainable approach towards the retrofit of the public housing building stock: Energy-architectural experimental and numerical analysis

Nowadays, energy retrofit interventions on the existing building stock are of paramount importance towards energy consumption and emissions reductions in the construction sector. Such interventions are also crucial in the view of increasing cities resilience with respect to the intensification of frequent extreme weather events, such as cold spells and heatwaves. Indeed, a wide portion of our cities is dated and lacking with respect to performances. These are the motivations behind the proposed sustainable approach, which deals with the environmental perspective, but also with social and economic ones, by proposing the retrofit of the Public Residential Building stock (Edilizia Residenziale Pubblica, ERP). The objective is to improve the energy performance of ERP stock by means of construction materials coming from local km0 agricultural waste and by-products. The research was conducted by means of in field and numerical analyses of the energy performances of a relevant case study building. Different layers of bio-based, recycled construction materials for the envelope were tested with respect to their efficacy in improving the energy performance of a case study building. The results demonstrate that the most performing envelope solutions and their combination are able to reduce up to 36% of the yearly energy consumption for heating