- University of Catania, Department of Civil Engineering & Architecture, Department Memberadd
The green transformation of the built environment is aimed at improving sustainability and can be supported by digitalization, which has become a significant tool to support the supply, integration, and management of information... more
The green transformation of the built environment is aimed at improving sustainability and can be supported by digitalization, which has become a significant tool to support the supply, integration, and management of information throughout the construction life cycle. In addition, climate change highly affects human comfort in the built environment and different strategies should be evaluated for adapting cities. This paper developed a digital workflow by integrating existing tools (i.e., Grasshopper, Ladybug, Honeybee, and Dragonfly) to evaluate how different green infrastructure strategies affected the thermal comfort by reducing the UTCI. The workflow was applied to a typical historical urban context (Catania, South of Italy), consisting of a square surrounded by three-floor buildings. Three basic scenarios were created that depended on the pavement material used in the built environment: a black stone pavement (reference material from Mount Etna), a permeable pavement, and grass. These three scenarios were combined with different green infrastructure strategies: tree pattern on the square, green walls and green roofs on the surrounding buildings, and the integrations of all these above-mentioned strategies. The results demonstrated that the integration of different green strategies (a grass square instead of pavement, with trees, and green walls and green roofs) increased the thermal comfort by reducing the UTCI by more than 8 °C compared to the existing urban context (black stone pavement and building envelope). However, this temperature reduction was highly affected by the location of the human body into the urban context and by the evaporation rates from vegetation. The workflow developed will be useful for designers to evaluate the effectiveness of different green strategies during the early-design stage in mitigating and adapting cities to climate change.
In the context of sustainable development and parametric design, it is interesting to analyze the possible synergies between Leadership in Energy and Environmental Design (LEED), the most-used certification scheme for the design,... more
In the context of sustainable development and parametric design, it is interesting to analyze the possible synergies between Leadership in Energy and Environmental Design (LEED), the most-used certification scheme for the design, construction, and management of green buildings, and Building Information Modeling (BIM), which supports the supply, integration, and management of information throughout the building life cycle. This paper aims to review the state of the art of the different integration methods between LEED and BIM at the early design phase. Third-party software information exchange, the cloud-BIM approach, and plug-in development using application program interface (API) were considered as possible integration strategies to automate LEED certification by BIM. In addition, optimization models and rule-based methods were analyzed. Finally, a critical review on the limitations, advantages and future research developments in LEED and BIM integration was clearly defined. Although the development of plug-ins was the most powerful integration method, it requires advanced informatics knowledge. On the other hand, using third-party tools increased manual working and checking due to interoperability issues. A visual programming language (VPL) can allow designers and researchers without any informatics knowledge to create parametric BIM models by including LEED requirements.
Green roofs are recognized as a solution able to reduce building energy consumption and to increase envelope thermal performance. Nowadays, new materials are continuously proposed and investigated for green roof layers to optimize... more
Green roofs are recognized as a solution able to reduce building energy consumption and to increase envelope thermal performance. Nowadays, new materials are continuously proposed and investigated for green roof layers to optimize environmental and economic sustainability. However, in absence of specific national and international standards for laboratory calculations of the thermal performance of substrate for green roofs, thermophysical characterization of substrates generally excluded that thermal conductivity should be modified as water content changes from dry to saturated. In this paper, a novel laboratory testing method was proposed to assess thermal conductivity of substrates for green roofs. The tests were performed by varying the water content into substrates and saturated, dry, and moist conditions were analyzed. Three commercial substrates different in composition were investigated. Thermal conductivity measurements were conducted using the HFM 436/3/1 Lambda and the TLS-100 devices to cross-referencing the measurements obtained. The results for all the substrates demonstrated that thermal conductivity fluctuates by varying water content. At moist conditions, the thermal conductivity value is an average between the one at saturated and dry conditions. The lower thermal conductivity is obtained in dry condition while the higher one is obtained in saturated condition due to water influence. Since the thermal conductivity was consistent with those provided by the company manufacturing commercial substrates, the proposed testing method could be considered reliable and it could be applied to different substrates, especially concerning the HFM Lambda device. This laboratory testing can potentially provide a useful guideline for assessing thermal conductivity of green roof substrates.
A growing trend regarding green roofs is the use of recycled and reused materials in their drainage and substrate layers, which can generate environmental, technical, economic, and aesthetic benefits while also providing the possibility... more
A growing trend regarding green roofs is the use of recycled and reused materials in their drainage and substrate layers, which can generate environmental, technical, economic, and aesthetic benefits while also providing the possibility of incorporating waste into the construction production chain. Except for the substrate, very few studies have investigated the potential to use recycled materials in other green roof layers. This article evaluates the thermal properties of polyethylene granules, derived by the recycling of waste plastic films used for greenhouse covering, as drainage layer in green roofs. To this end, a laboratory testing method was proposed to assess the thermal conductivity of drainage layer materials. The tests were performed for the recycled polyethene, expanded clay and perlite, these last as commercial products, by varying the water content. Thermal conductivity measurements were conducted using the HFM 436/3/1 Lambda and the TLS-100 equipments to cross-referencing the measurements. The results demonstrated that. perlite had thermal conductivity lower than both expanded clay and polyethylene in both moist and dry conditions. Differently, by increasing the water content, perlite had the highest thermal conductivity due to the hygroscopic material structure and polyethylene had the lowest thermal conductivity. This result is significant because recycled polyethylene, being a recycled material, can increase the sustainability of green roofs while reducing costs compared to expanded clay and perlite. In addition, by comparing the thermal conductivity determined with the proposed testing procedure to the thermal conductivity provided by the perlite manufacturer, it can be observed that the results are similar. Therefore, the proposed testing method may be considered reliable, and it could be used for the evaluation of the thermal conductivity of granular materials.
Although green roofs are considered among the most sustainable building envelopes, an expanding tendency is the use of recycled or reused materials and low-cost products to improve their environmental and economic sustainability. This... more
Although green roofs are considered among the most sustainable building envelopes, an expanding tendency is the use of recycled or reused materials and low-cost products to improve their environmental and economic sustainability. This article evaluated the use of polyethylene granules, derived from the recycling of agricultural plastic waste coming from greenhouse covering, as drainage layer in green roofs. To this end, the physical properties (i.e. particle size, specific weight, minimum and maximum density and permeability) of five different recycled plastic granules were determined. Moreover, the thermal conductivity of one of these recycled products was assessed through a customized testing methodology varying the water content. Thermal conductivity measurements were conducted by using two pieces of equipment to cross-referencing the measurements. The same surveys were carried out on other granular drainage materials (i.e. perlite, expanded clay) to validate the proposed methodology as well as to compare the thermal performance of the examined materials. The results of the thermo-physical tests showed that the recycled plastic granules have features within the range requested for green roof drainage layer, very similar to those of perlite and, therefore, they may be used as an alternative to natural drainage materials. In addition, recycled polyethylene had mechanical and environmental performances better than commercial products, indeed it has the lowest weight increase in saturated conditions, about 80 kg/m³, so reducing the extra load applied on existing building rooftops, as well it produces very low Global Warming Potential (GWP) impact, that is 2–4 kgCO2eq/FU. These outcomes could have wide dissemination considering that Europe is one of the major consumers of agricultural plastic products and their reuse/recycling comply with the ecological transition objectives.
Although green roofs are mentioned among the most sustainable building envelope solutions, there is the need to replace current green roof materials by more environmentally friendly and low-cost products, proposing innovative... more
Although green roofs are mentioned among the most sustainable building envelope solutions, there is the need to replace current green roof materials by more environmentally friendly and low-cost products, proposing innovative technological solutions developed for Mediterranean area. In addition, Italy is one of the major consumers of agricultural plastic products but recycling of a substantially increased amount of plastic waste may lead to a supply surplus of secondary material. To mitigate this risk, applicability of the current secondary material needs to be increased. In this paper, the use of polyethylene granules from the recycling of agricultural plastic waste used for greenhouse covering as drainage layer in green roofs is evaluated. The physical properties (i.e. particle size, specific weight, minimum and maximum density and permeability) of five recycled plastic granules different in recycling process are determined through laboratory tests in compliance with ASTM Standards and compared with those of perlite, the granular material commercially used for the drainage layer. The results showed that the recycled plastic granules have physical properties comparable to those of perlite and, therefore, they are suitable for the drainage layer in green roofs. Among plastic materials, those coming from the waste of polyethylene recycling have better characteristics as possible drainage layer because they have lower specific weight and lower minimum and maximum density compared to the granule produced according to UNI 10667-1, thanks to the air gaps inside the granule. In addition, they have a lower permeability thanks to higher particle size and to the cavities on the granule surface that allow water storage and evaporation, providing support to vegetation development. Future research will evaluate the thermal properties of recycled granules in both laboratory, both in dry and saturated conditions, and full-scale set-ups, using recycled granule as drainage layer.
Green roofs were proposed to broaden nature-based solutions within the perspective of the ecological transition for the built environment. In this paper, an innovative and sustainable green roof was designed to optimize the energy... more
Green roofs were proposed to broaden nature-based solutions within the perspective of the ecological transition for the built environment. In this paper, an innovative and sustainable green roof was designed to optimize the energy performance in Mediterranean area during summer season by means of local-available and recycled materials, thus reducing the environmental impacts. This new green roof technology consisted of recycled polyethylene granules from the regeneration of disused agricultural plastic films as drainage layer and a substrate made of local-sourced materials with high percentage of organic matter and it was compared to two traditional green roofs and to the existing roof. The energy-efficient design was based on the thermo-physical parameters of the green roof (surface temperatures, heat flows and volumetric water content) and of the building (surface temperature of the ceiling) and on the thermal dynamic parameters (decrement factor, time lag and cooling potential). In addition, these thermo-physical parameters were correlated to the Mediterranean climate during summer season. The result demonstrated that although the proposed green roof reached higher surface temperatures than commercial solutions, it maintained an almost constant volumetric water content, it reduced daily fluctuations between minimum and maximum temperatures, it resulted in lower thermal flow through the cross-section, it reduced the surface temperatures inside the building by about 2 °C compared to the traditional roof, thus decreasing the energy consumption for building cooling and greenhouse gas emissions, and it had better dynamic thermal performance than commercial green roofs. Once the energy-efficient design of the proposed green roof technology was proved, the sustainability and the life cycle performance of the recycled polyethylene was discussed, also considering the costs.
Green roof promises to become an increasingly important option for building owners and community planners because it can address many of the challenges facing urban residents. The success of the roof depends on the specific build-up of... more
Green roof promises to become an increasingly important option for building owners and community planners because it can address many of the challenges facing urban residents. The success of the roof depends on the specific build-up of the green roof, therefore, special attention was focused on the identification and application of more environmentally friendly materials in green roofs. However, except the substrate, very few studies have denoted the potential to use reused materials for drainage layers, despite its important role in determining thermal and hydraulic performance of green roofs. This study analyzes the scientific literature on the use of innovative materials from the recovery/recycling of products for the drainage layer and propose the use of low-density polyethylene (LDPE) granules coming from the recycling of waste films used in agriculture for greenhouse roofing and mulching as innovative and sustainable drainage material in green roofs. In addition, the proposal concerns the possibility to enclose the plastic granular material into micro-perforated bags made of recycled polyethylene and to use the soil coming from washing of agricultural films as substrate in green roofs. This proposal will be further investigated by laboratory assessment on the thermo-physical properties of several polyethylene granules and by experimental set-up having the goal of assessing the thermal performance of different green roof technologies, in order to represent a suitable alternative to materials commercially used from an environmental, economic, and social point of view.
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... more
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.
The research presented in the following paper aims to develop a sustainable emergency construction system based on natural materials and reversible systems. The current need for temporary shelters has raised, due to the increasing number... more
The research presented in the following paper aims to develop a sustainable emergency construction system based on natural materials and reversible systems. The current need for temporary shelters has raised, due to the increasing number of disasters affecting urbanized areas or their significant degradation. A viable solution is the use of prefabricated elements, which guarantees benefits in terms of both costs, and speed of assembly and disassembly. A thorough design of the construction components guarantees the reversibility of the construction and therefore the reuse of the structure for the same or other purposes. However, the benefits provided by sustainable prefabricated constructions make these systems suitable for multiple uses, considering both the design and construction phase and the indoor comfort provided during the building life. In fact, during the planning phase, the life cycle assessment of the materials is taken into account, resulting in the choice of natural materials that involve little to no resources consumption. The aim of the study is to assess the thermal behavior of a few different coating panels built with natural materials, used in combination with the designed prefabricated system, in order to identify a range of values that can be set as reference for similar systems. The first part of the paper introduces the implemented construction system, while the second part focuses on the characterization of the envelope coating panels, in order to achieve optimal overall thermal performance. The characterization of the panel samples was carried out in laboratory using a heat flow meter.
The urban contexts that we live today are often the result of a stratification spontaneously followed over time, incorporating buildings in use in ancient times but abandoned as a result of the historical and cultural evolution of the... more
The urban contexts that we live today are often the result of a stratification spontaneously followed over time, incorporating buildings in use in ancient times but abandoned as a result of the historical and cultural evolution of the city. This situation is very frequent in many historical centers, where archaeological buildings are located below the modern urban plan. An exemplary case of this situation is given by the Roman amphitheater of Catania. It was covered and used as a substructure for the new plan steal and for the buildings rebuilt after the earthquake of 1693 that destroyed the city. These reconversions of ancient structures cause several conservative problems, often difficult to understand and which must be investigated in an interdisciplinary way to understand their origins and solve them. The complexity of urban systems requires an inevitable multidisciplinary approach that combines archival analysis, historical, archaeological analysis, diagnostics, architectural, plant engineering and urban. This research aims to show, in particular, how the part of historical analysis of archival type can be a useful diagnostic survey tool to be applied in multi-layered contexts, through the example of the Roman amphitheater of Catania which today is in a precarious state of conservation and accessibility that requires intervention. This work was carried out by studying the administrative documentation of the 19th century produced by responsables for the protection of the historical buildings of Catania, kept at the State Archive of Catania, and allowed to understand the conservative events of the heritage architectures and to deepen the knowledge of the causes of the degradation that today the monument undergoes, demonstrating how such problems have a long history never radically resolved. Keywords: urban stratification, archive research, history of conservation, diagnostic.
Il giardino della nobildonna inglese Lady Florence a Taormina, oggi Parco Giovanni Colonna, Duca di Cesarò, realizzato alla fine del XIX secolo, durante un’importante momento di rinascita e turismo elitario che vede nella città sicula una... more
Il giardino della nobildonna inglese Lady Florence a Taormina, oggi Parco Giovanni Colonna, Duca di Cesarò, realizzato alla fine del XIX secolo, durante un’importante momento di rinascita e turismo elitario che vede nella città sicula una meta privilegiata, rappresenta un vero e proprio emblema del gusto inglese diffusosi nel Sud Italia già dalla fine del 1700. Esso, in coerenza con gli stili del giardino romantico inglese, si caratterizza per un forte eclettismo dato dal connubio tra elementi mediterranei ed elementi esotici orientali. Emblema di questa eterogeneità sono le torrette dette “beehives” fatte costruire dalla nobildonna come luoghi di svago ispirandosi alle pagode orientali. Ad oggi lo stato di conoscenza e conservazione di tali strutture risulta molto compromesso a causa della mancata manutenzione. Proprio per tale ragione è stato previsto un intervento di recupero teso alla messa in sicurezza di parte dei beni architettonici presenti così da riconsegnarli alla pubblica fruibilità e godibilità che meritano e ad ora impossibilitata. Alla luce di tale previsione, si presenta in tale sede una ricerca finalizzata ad incrementare la parte conoscitiva del contesto e delle sue strutture oggetto di restauro, nello specifico della torretta maggiore del giardino (torretta 4), al fine oltre che di avviare un primo supporto alle indagini preliminari al progetto, anche di incrementare la conoscenza e l’interesse a pianificare futuri e più mirati approfondimenti nei confronti di un luogo tanto d’eccezione quanto sottovalutato.
Plastic films can be considered as a high-value auxiliary material in agriculture with multiple important uses to fulfil, including covering films in greenhouse cultivation system. Such an application enables several benefits and,... more
Plastic films can be considered as a high-value auxiliary material in agriculture with multiple important uses to fulfil, including covering films in greenhouse cultivation system. Such an application enables several benefits and, therefore, it is going through an important upsurge, especially in regions where protected crop cultivation is highly widespread. However, the increased demand for these covering films arouses concerns for their post-use treatment with regard to both the consumption of Non-Renewable Primary Energy (NRPE) resources and the emission of Greenhouse Gases (GHGs). Therefore, environmental analysis is needed to find and follow cleaner paths for the management and treatment of this kind of Agricultural Plastic Waste (APW), especially in the light of the gap currently existing in the specialised literature. In this context, this paper reports upon findings from a combined Life Cycle Assessment (LCA) of single environmental issues (i.e., energy and water consumption, and GHG emissions) applied to a Sicilian firm, representative of APW collection and recycling to obtain Low-Density Polyethylene (LDPE) granules. The results showed that electricity consumption for the whole recycling process is the most NRPE resource demanding and the most GHG emitting input item. Moreover, the washing phase of disused covering films is the highest water demanding within the recycling process. Potential improvements could be achieved by shifting from fossil energy source to renewable one. The installation of a wind power plant would lead to around 56% and 85% reduction in NRPE resource exploitation and GHG emission, respectively. Finally, despite the huge consumption of water and NRPE resources and the resulting GHG emissions, the production of recycled-LDPE granules is far more sustainable than the virgin counterpart.
Green roofs performance have been widely investigated over the past few years, since they offer a series of benefits under different aspects: not only do they contribute to increase green areas inside the urban center from an... more
Green roofs performance have been widely investigated over the past few years, since they offer a series of benefits under different aspects: not only do they contribute to increase green areas inside the urban center from an environmental point of view, but also they meet several energy performance requirements, when they are well designed. In fact, these systems alter the heat flow through the roof covering, therefore affecting the energy balance inside the building. The majority of the studies present in literature have focused on characterizing extensive and intensive green roofs and their layer composition, on the other hand there is a lack of studies that pursue the assessment of these systems thermal performance from a more engineering point of view, with the target to set thermal conductivity and thermal resistance standards in order to use them as insulation components. The aim of the study presented in this paper is to propose a laboratory testing method that can be used to assess substrates thermal characteristics in order to find reference values for common growing media and also for testing the performance of new ones. This would provide more options to select from, also based on the availability of a specific material in different areas, increasing the environmental benefits that these systems already offer. A viable option is perhaps testing recycled and waste materials to assess how they would perform as green roof substrate layer. Further tests on green roof layers energy performance meant to define reference values would fill the gap between theoretical studies on their benefits and actual day to day use.
The progressive modification of the land surface in the urban area during the last decades has involved an increase in urban air temperature compared to surrounding rural areas. The significant replacement of green areas with built... more
The progressive modification of the land surface in the urban area during the last decades has involved an increase in urban air temperature compared to surrounding rural areas. The significant replacement of green areas with built surfaces characterized by high solar radiation favored the energy storage during the day and heat release in the nocturnal hours. The Urban Heat Island (UHI) is an emblematic effect of the increase of urban temperature which in turn affects the energy consumption in the building sector. Several passive building technologies are available to mitigate the UHI phenomenon and reduce the energy consumptions in buildings. In the Mediterranean climate, where the solar radiation control is the most important passive strategy in summer, cool roof technology is able to reduce the solar radiation absorbed by materials and to limit the outer superficial temperature in the presence of high solar loads. This paper presents a numerical analysis of the energy and environmental performance of an office building equipped with a cool roof for three different climate zones. Dynamic simulations highlight the different thermal behavior of the investigated cool roof in comparison to the standard roof, also as a function of the roof thermal resistance. Moreover, the Solar Reflectance Index (SRI) of the different roof configurations has been evaluated. It was found that slight or no insulated cool roofs has the lowest superficial temperatures and hence mitigates the UHI.
Nel panorama attuale, la riqualificazione energetica del patrimonio costruito è di fondamentale importanza per ridurre i consumi e le emissioni che provengono dal settore delle costruzioni. Questi interventi inoltre sono di primaria... more
Nel panorama attuale, la riqualificazione energetica del patrimonio costruito è di fondamentale importanza per ridurre i consumi e le emissioni che provengono dal settore delle costruzioni. Questi interventi inoltre sono di primaria importanza anche per aumentare la resilienza delle città nei confronti dei fenomeni climatici estremi, sempre più frequenti, quali le ondate di freddo (cold spells) e quelle di calore. Ciò è di particolare rilievo in quanto buona parte del costruito delle nostre città è datato e carente dal punto di vista prestazionale. Queste motivazioni spingono gli autori a considerare un approccio sostenibile alla realtà urbana non solo dal punto di vista ambientale, ma anche sociale ed economico, proponendo la riqualificazione dell’Edilizia Residenziale Pubblica per migliorarne la prestazione energetica, analizzando l’efficacia dell’impego di materiali isolanti provenienti da scarti e sottoprodotti dell’agricoltura a km0. Lo studio proposto è condotto mediante indagini sul campo e analisi numeriche della prestazione energetica di un edificio scelto come caso di studio, con e senza l’applicazione sull’involucro murario di diverse soluzioni (per materiali e stratigrafia) che utilizzano materiali naturali di scarto riciclati. La ricerca è portata avanti mediante indagini sul campo, in un edificio esistente (complesso residenziale romano di Val Melaina, costruito dall’ICP a inizio Novecento), esemplificativo di una certa parte del patrimonio suddetto. I risultati numerici della modellazione, validata, dimostrano come le più performanti soluzioni proposte per l’involucro opaco siano in grado di ridurre del 27% in consumo annuale di energia per il riscaldamento, mentre, agendo contemporaneamente sia sull’involucro opaco che su quello trasparente, lo stesso consumo è stato ridotto del 38%.
Construction is one of the sectors with the higher CO2 emissions. To evaluate the building environmental impacts, it is necessary to consider all the life cycle phases: from the extraction of raw materials to their disposal. In the last... more
Construction is one of the sectors with the higher CO2 emissions. To evaluate the building environmental impacts, it is necessary to consider all the life cycle phases: from the extraction of raw materials to their disposal. In the last years, the improvement in building energy efficiency has increased the energy savings during the operational phase, without reducing the impacts in the material production. For this purpose, several researches showed that natural materials are comparable to commercial synthetic products in terms of thermal and acoustic performance. In particular, agricultural by-products, used as building thermal insulation, allow positive impact on CO2 emissions. The general aim of this review paper is to find solutions to minimize the energy consumption during building construction, in both raw material extraction and transportation. In particular, this paper carried out a literature review on the use of agricultural waste materials as thermal insulators. The construction technique and the binder type to create panels were assessed, providing a critical analysis on the future perspective in this sector.
Straw bale buildings provide significant benefits in terms of costs, human health, and environmental sustainability. Several studies in different regions have underlined the remarkable properties of straw bales as insulating and... more
Straw bale buildings provide significant benefits in terms of costs, human health, and environmental sustainability. Several studies in different regions have underlined the remarkable properties of straw bales as insulating and construction material; however, to the authors’ knowledge, there are no reviews published on this topic. The main objective of this paper is to provide a better understanding of straw bale systems, focusing on durability and thermal and acoustic insulation properties. To this end, previous tests and studies on straw bale buildings around the world were reviewed, comparing their results, assessing where research currently stands, and identifying the aspects that need to be further investigated. Results from previous tests have highlighted their ability to achieve excellent living comfort and encouraged their use. Guidelines for the characteristics to be achieved during the baling process are now required. Combining straw bale walls with a render or any type of high-density layer can improve both the thermal and acoustic properties of straw bale constructions. Finally, a quantitative assessment of the most significant properties, such as thermal resistance and acoustic insulation, is necessary to reduce the gap between straw bales and traditional building materials.
The Ph.D. research deals with the study of different green roof configurations by varying the materials used, in order to propose an innovative technological solution developed for areas with Mediterranean climate. In addition, this... more
The Ph.D. research deals with the study of different green roof configurations by varying the materials used, in order to propose an innovative technological solution developed for areas with Mediterranean climate. In addition, this research aims to increase the scientific knowledge on building passive cooling, which is one of the main benefits of green roofs. Firstly, a thorough bibliographical survey was carried out, concerning both the technological aspects and the evapotranspirative cooling due to green roofs. The numerical analysis involved the performance of different commercial solutions, in order to identify those with the highest energy performance in Mediterranean climate, even in the case of building retrofitting. Based on scientific literature and numerical analysis results, two experimental set-ups have been designed and installed. The first, built at the University of Lleida (Spain), had the objective of assessing the passive cooling due to evapotranspirative phenomena of green roof, varying the irrigation regime, and correlating it both to the energy performance and to the microclimatic conditions. The second, built at the University of Catania, aims to determine the energy performance of an innovative technology that involves the polyethylene granule, coming from the regeneration of films released in agriculture, as a drainage material. Furthermore, an LCA analysis was performed to assess the environmental impacts of the granule production process, identifying possible improvements. Finally, a substrate with a higher percentage of organic matter than traditional ones was created with the aim of increasing water retention and decreasing the amount of water provided by the irrigation system.
This research is aimed at evaluating the energy performance of an existing building in Mediterranean climate, and to assess the benefit coming from various retrofit solutions of the building envelope, such as green roof and facades. By... more
This research is aimed at evaluating the energy performance of an existing building in Mediterranean climate, and to assess the benefit coming from various retrofit solutions of the building envelope, such as green roof and facades. By means of dynamic simulations, validated with experimental results, the reduction in both internal air temperature and cooling load was estimated. In addition, the impact of the green shielding on the windows in terms of indoor visual comfort was assessed, and suitable soluitons were envisaged.
This paper studies the thermal and acoustic performance of straw bale walls used in timber-frame semi-detached houses recently built in Sicily (Southern Italy), and compares them to similar walls where expanded polystyrene (EPS) is... more
This paper studies the thermal and acoustic performance of straw bale walls used in timber-frame semi-detached houses recently built in Sicily (Southern Italy), and compares them to similar walls where expanded polystyrene (EPS) is adopted in place of the straw bales. In-situ measurements were carried out to analyse the acoustic performance of both wall typologies. The weighted Apparent Sound Reduction Index for the partition wall between two houses, as well as the weighted Standardized Level Difference for the façades were assessed based on the ISO Standards 16283. Moreover, the two insulating solutions were compared in relation to their steady and dynamic thermal performance. The results underline that the acoustic performance of the straw bale walls is far better than the walls adopting traditional EPS insulation. However, slight improvements are suggested to further increase the sound insulation properties of straw bales. On the other hand, EPS is a more effective thermal insulation even if straw bale walls comply with Italian standards. Finally, the dynamic performance of straw bales should be improved by increasing their density. Overall, the proposed straw bales used can be conveniently used in low-energy and n-ZEB buildings in warm and mild countries.
More than 95% of the property confiscated from the mafia is concentrated in eight Italian regions, with a clear prevalence of Sicily (40%). Most of these buildings are degraded and abandoned and must be recovered with change of intended... more
More than 95% of the property confiscated from the mafia is concentrated in eight Italian regions, with a clear prevalence of Sicily (40%). Most of these buildings are degraded and abandoned and must be recovered with change of intended use. Moreover, in many Italian cities, the households with living discomfort is increasing, mainly due to social and economic fragility. This paper examines the functional recovery and structural consolidation of a building located in a suburban area in Catania (Sicily), to turn it into a social hotel. The community activities are placed on the ground floor while the private activities are on the first floor. Moreover, the external areas were used to create a space for social agriculture. The seismic improvement has been achieved thanks to steel bracing included into the building envelope. In addition to complying with the standards on seismic constructions, technological solutions have been aimed at reducing energy consumption and greenhouse gas emission using natural materials. The results show that the reuse of property confiscated from the mafia can help to increase the housing supply from people feeding the temporary emergency.
This paper investigates the performance of timber-framed walls insulated with straw bales, and compares them with similar walls containing expanded polystyrene (EPS) instead of straw bales. First, thermal conductivity, initial water... more
This paper investigates the performance of timber-framed walls insulated with straw bales, and compares them with similar walls containing expanded polystyrene (EPS) instead of straw bales. First, thermal conductivity, initial water content, and density of the straw bales were experimentally measured in a laboratory set-up, and the dependence of the thermal conductivity of the dry material on temperature was described. Then, the two insulation solutions were compared by looking at their steady and periodic thermal transmittance, decrement factor, phase shift, internal areal heat capacity and surface mass. Finally, the acoustic performance of both wall typologies was analyzed by means of in situ measurements in two-story buildings built in Southern Italy. The weighted apparent sound reduction index for the partition wall between two houses and the weighted standardized level difference for the façades were assessed based on ISO Standard 16283. The results indicate that the dry straw bales have an average thermal conductivity of k = 0.0573 W/(m·K), and their density is around 80 kg/m3. In addition, straw bale walls have good steady thermal performance, but they still lack sufficient thermal inertia, as witnessed by the low phase shift and the high periodic thermal transmittance. Finally, according to the on-site measurements, the results underline that the acoustic performance of the straw bale walls is far better than the walls adopting traditional EPS insulation. Overall, the straw bales investigated are a promising natural and sustainable solution for thermal and sound insulation of buildings.
Previous research has shown that most of the green roof benefits are related to the cooling effect. In the literature available, however, it is still not clear how and how much the evapotranspiration affects the performance of a green... more
Previous research has shown that most of the green roof benefits are related to the cooling effect. In the literature available, however, it is still not clear how and how much the evapotranspiration affects the performance of a green roof. In order to fill the gap in this research topic, this study carries out a review on the cooling effect due to the evapotranspiration process of green roofs. First of all, an overview of the evapotranspiration phenomenon in green roofs, as well as the equipment and methods used for its measurement are presented. Then, the main experimental results available in literature, the physical-mathematical models and the dynamic simulation software used for the evaluation of the latent heat flux are also analysed and discussed among the available literature. Moreover, this review proposes a classification of the results carried out by previous studies as function of the main parameters affecting the evapotranspiration process (e.g. volumetric water content, stomatal resistance, Leaf Area Index, solar radiation, wind velocity, relative humidity, soil thickness, and substrate composition). Additionally, a sensitivity analysis of the results obtained from the literature allowed underlining the correlation among the main factors affecting the evapotranspiration. Finally, a vision of the world area where green roof studies were performed is provided. From the results, it is possible to emphasize that most of the studies that evaluated the evapotranspiration used high precision load cells. Furthermore, all the heat transfer models of green roofs considered in this review took into account the latent heat flux due to evaporation of water from the substrate and plants transpiration, however, only few of them were experimentally validated.
Il settore delle costruzioni manifesta oggi un crescente interesse neiconfronti dei temi della sostenibilità e della bioedilizia. Ciò si traduce inun progressivo aumento dell ’uso dei materiali naturali, ampiamentedisponibili sul... more
Il settore delle costruzioni manifesta oggi un crescente interesse neiconfronti dei temi della sostenibilità e della bioedilizia. Ciò si traduce inun progressivo aumento dell ’uso dei materiali naturali, ampiamentedisponibili sul territorio e a basso impatto ambientale, come il legno e lapaglia.Il presente lavoro documenta un ’attività sperimentale finalizzata allavalutazione delle caratteristiche di isolamento termico e acustico dellapaglia attraverso prove di laboratorio e misurazioni in opera effettuate inedifici residenziali con struttura in legno. Sono state confrontate le prestazioni di isolamento della paglia conquelle del polistirene espanso, giungendo alla conclusione che, nonostantenecessiti di un attento controllo in fase di progettazione e di messa inopera, a causa della sua natura organica e deperibile, la paglia può essereconsiderata una valida alternativa agli isolanti di origine sintetica, sia intermini prestazionali, sia a livello economico.
The towers located along the Sicilian coasts attest a past in which they constituted a defence point for the population and a haracterizing sign of the surrounding landscape, which often grew around them. These towers represented, and... more
The towers located along the Sicilian coasts attest a past in which they constituted a defence point for the population and a haracterizing sign of the surrounding landscape, which often grew around them. These towers represented, and still represent, an historical and environmental element of value. Today, most of the fortifications built in Sicily for defensive purposes are in a bad state of conservation, generally due to the presence of biological degradations – among which the outside infesting vegetation appears to be the preponderant – and following dangerous instability. These forms of egradation are often accompanied by a poor state of preservation of the interior spaces. In order to preserve the historical and cultural identity of these historical buildings, and consequently of the surrounding landscape, it is necessary to reach, although in part, the ncient magnificence obtained during the Kingdom of Sicily of Frederick II, when the most important noble houses of the time began a vast building work. Despite the difficulties of intervention deriving from the historical and architectural instance, the fortifications can be recovered through two combined actions, i.e. the use of a onservative approach based on punctual and minimal interventions and the adoption of a BIM approach for the management restoration activities and optimization of the subsequent maintenance and management of the building. The present research, focusing on the case study of the Faraglione Tower of Aci Castello di Catania locally called "Bastioncello", illustrates an example of conservative restoration supported by the use of a BIM methodology to obtain an optimal recovery intervention.
The farmhouses, symbol of the landed property, are at the same time productive and residential settlements with the objective of controlling and organizing the landed estate. In Sicily, their appearance coincides with the colonization... more
The farmhouses, symbol of the landed property, are at the same time productive and residential settlements with the objective of controlling and organizing the landed estate. In Sicily, their appearance coincides with the colonization phenomenon of inland areas for agricultural purposes. These building structures, once at the center of productive, economic and social activity, are very often abandoned and degraded. Their recovery and reuse as tourist structures or for cultural and naturalistic purposes can contribute ffectively to the preservation of the traditional rural heritage and the enhancement of the agricultural landscape. This article shows the results of a research aimed at recovering and re-using rural buildings. The project for the transformation of a farmhouse, chosen as a case study in the Ibleo plateau, in didactic farm is illustrated.
In order to consider green roofs as an environmentally friendly technology, the selection of efficient and sustainable components is extremely important. Previous review papers have mainly focused on the performance and advantages of... more
In order to consider green roofs as an environmentally friendly technology, the selection of efficient and sustainable components is extremely important. Previous review papers have mainly focused on the performance and advantages of green roofs. The objective of this paper is to examine the primary layers: The waterproof and anti-root membranes; the protection, filter, and drainage layers; the substrate; and the vegetation. First, the history, modern applications, benefits and classification are analyzed in order to present a well-defined state of the art of this technology. Then, the roles, requirements, characteristics, and materials are assessed for each green roof layers. This technology was compared to a conventional roof technology, Mediterranean climate conditions and their influence on green roof design were assessed, also comparing them with Tropical area and focusing on irrigation systems, examples about the commercial materials and products available in the market were provided and innovative materials coming from recycled sources were analyzed. Future research should evaluate new materials for green roof technologies, in order to enhance their performance and increase their sustainability. The information provided in this review paper will be useful to develop Mediterranean green roof guidelines for selecting suitable components and materials during the design and installation phases.
Green roofing is a sustainable solution for building energy saving, urban heat island mitigation, rainwater management and pollutant absorption. The effectiveness and performance of green roofs depend on layer composition and properties.... more
Green roofing is a sustainable solution for building energy saving, urban heat island mitigation, rainwater management and pollutant absorption. The effectiveness and performance of green roofs depend on layer composition and properties. The uncertainties surrounding green roof performance modeling are mainly related to the vegetation and substrate layer, which are subjected to surrounding climatic conditions. Energy simulation software typically does not use validated models encompassing all possible combinations of vegetation layers and substrates. Therefore, the objective of this research is to investigate different extensive green roof solutions for assessing thermal performance and to provide information on vegetation and substrate layer design. Different simulations executed in EnergyPlus were carried out based on realistic literature data drawn from previous experimental tests conducted on plants and substrates. Several combinations (30 plant-substrate configurations, six vegetative species and five types of substrates) were defined and evaluated. Furthermore, indexes based on the surface temperatures of green roofs were used. Finally, a comprehensive ranking was created based on the scores to identify which extensive green roof combinations offered the highest performance. Greater plant heights, LAI values and leaf reflectivity values improve green roof energy performance in the summer more significantly than substrate modification. During the winter, thermal performance is more heavily dependent on the substrate if succulent vegetation is present, regardless of the substrate used. These results could provide designers with useful data at a preliminary stage for appropriate extensive green roof selection.
In recent years, Building Information Modeling (BIM) has changed the traditional construction process, emerging as a key tool for building management throughout the entire life cycle. The base of the BIM methodology is the realization of... more
In recent years, Building Information Modeling (BIM) has changed the traditional construction process, emerging as a key tool for building management throughout the entire life cycle. The base of the BIM methodology is the realization of a model that, updatable with the changes made to the building, is able to contain in a single three-dimensional interface a virtual representation of the building, including the real information about its constructive and plant components. Among the existing building heritage into the Italian cities, more importance is given to the historical-monumental buildings, as the largest number of UNESCO world heritage sites are located in Italy. The information storage of these buildings is a fundamental phase, for both the high amount of data and the aim of their cataloguing, necessary for the proper conservation of the building and its future management. In order to achieve these goals, the information to be associated with each building component are not only geometric and dimensional, but also related to maintenance aspects, because the management phase of the historical-monumental buildings is temporally predominant compared to the other life cycle phases. The present research, analysing the case study of the Collegio dei Gesuiti located in the city of Catania and characterized by high historical-monumental and cultural value, aims to combine the use of the BIM methodology with the correct maintenance planning and management activities. With this purpose, this study focused on some building components, both structural and non-structural. These elements, carefully analysed and surveyed, have been modelled by using a BIM software. Then, they were integrated with the information able to guarantee adequate support to the future activities led to preserve the historical building. The results show that the BIM methodology can be a key tool able to preserve the historical-architectural heritage that characterizes Italian cities.
Although it is difficult to determine the amount of energy used in building sector, several studies es-timated that the energy consumed by buildings accounts for about 40% of total consumption and buildings produce about 36% of global... more
Although it is difficult to determine the amount of energy used in building sector, several studies es-timated that the energy consumed by buildings accounts for about 40% of total consumption and buildings produce about 36% of global greenhouse gas emissions. The interest in environmental is-sues has led researchers and companies to investigate various technological solutions aimed at re-ducing emissions of polluting gases into the atmosphere, improving air quality and reducing build-ing energy consumption. The ongoing research proposes and examines different solutions of opaque building envelope, specially developed for areas with Mediterranean climate, able to contain energy consumption for building heating and cooling and to contribute to the reduction of environ-mental pollution. In particular, it is examined the replacement of traditional coating materials used for flat roofs with green roofs. The research on green roofs involved, in a first phase, the performance analysis of several commercial technological solutions, through the use of specific indexes, in order to define the solutions with the highest energy performance in Mediterranean climate, also using green roofs for the retrofitting of existing buildings. A specific focus of the research aims to investi-gate the evapotranspiration phenomenon which plays a key role in the heat exchanges between the green roof and the surrounding environment. In order to increase the sustainability, an innovative green roof solution is being developed using materials from the recycling of waste products. Finally, during the research, the performance of different vertical envelope technologies, such as green fa-cades and "platform frame" wooden system, were analyzed. For the latter, in particular, the energy and environmental performance were evaluated considering the filling of the interspace with a layer of compressed straw.
During recent years, the number of natural and non-natural disasters has drastically increased, due to the climate change, causing great damages on buildings and a high number of homeless people. However, post-disaster temporary housing... more
During recent years, the number of natural and non-natural disasters has drastically increased, due to the climate change, causing great damages on buildings and a high number of homeless people. However, post-disaster temporary housing solutions seem to have sustainability problems. Through a historical excursus, this work aims to analyse the steps that led to the current idea of temporary housing, in order to evaluate its functional and constructive characteristics. Finally, some considerations on improving thermal environment inside temporary housings are discussed.
The increasing awareness in the limited availability of fossil energy resources and the negative effects on the environment caused by their use moves the scientific research towards the development of new technological solutions in order... more
The increasing awareness in the limited availability of fossil energy resources and the negative effects on the environment caused by their use moves the scientific research towards the development of new technological solutions in order to reduce the energy and environmental impacts of buildings. This especially happens in Italy, where almost 90% of the buildings were built before the enforcement of any laws on building energy saving. This paper aims at evaluating the energy behavior of an existing building located in the city of Catania, characterized by Mediterranean climate. In particular, the contribution of different retrofitting envelope solutions was assessed, such as green roofs and green façades. The present study could be divided into two phases: the first phase was aimed at identifying the most suitable technological solution to improve the energy efficiency of the existing building; the second one was aimed at quantifying the energy aspects of different green system combinations integrated into the envelope. Furthermore, using dynamic simulations validated by experimental results, it was found that the green façade with a dense foliage allowed the greater reduction in the indoor air temperature. As a consequence, a reduction in the cooling load by 32% was obtained. Therefore, the study shows that green facades are a viable solution for limiting energy consumption in buildings, allowing economic savings during the operational phase of the building. Finally, green facades also allowed environmental benefits, contributing to the improvement of the urban microclimate, to the mitigation of the urban heat island and to the reduction in pollutant emissions.
In recent years, important changes have affected the fields of architecture and engineering , revolutionizing the traditional construction process. Among these, the Building Information Modeling is a key tool for the design and management... more
In recent years, important changes have affected the fields of architecture and engineering , revolutionizing the traditional construction process. Among these, the Building Information Modeling is a key tool for the design and management of the building during the entire life cycle, from its construction, maintenance and restoration to its disposal. In order to make this tool effective, it is necessary to develop a methodology that integrates the different types of information contained in the virtual BIM model, including the interventions on both the building heritage and architectural emergencies. The realization of the BIM model, and the following integration of building components information, is particularly complex in the case of historical-monumental buildings, both for the geometric-architectural complexity that characterizes them and for the high amount of associated information. These can be partly found through the reconstruction of the building history and integrated with the geometric survey of the building in its current configuration. In particular, among the information of the historical building that can be included in the "virtual archive" associated to the BIM model, those relating to the maintenance phase are the most relevant. In fact, this phase is predominant for temporal extension compared to the other phases characterizing the entire life cycle of the building. Moreover, the planning phase of maintenance works related to the architectural and monumental heritage is an issue, especially in recent years, due to the increasing awareness about the recovery and re-use of historical and cultural heritage. The present research, through the analysis of the case study of the Jesuits College of Catania, aims to combine the use of the BIM methodology with suitable planning and management of the maintenance activities addressed to the building case of study, characterized by a high historical-monumental value. In particular, this study analyses some structural and non-structural building components, which have been modelled and completed with the information necessary to guarantee, in the future, both a reduction in design and economic uncertainties and a rational management of the heritage .
The increasing awareness of issues like climate change and reduction of available fossil resources moves scientific research into the development of new technological solutions in order to reduce the energy and environmental impact of... more
The increasing awareness of issues like climate change and reduction of available fossil resources moves scientific research into the development of new technological solutions in order to reduce the energy and environmental impact of buildings. Hence, in recent years, key concepts such as energy saving and environmental sustainability affected both the design of new buildings and the retrofitting of existing buildings. The present study aims to evaluate the energy behavior of an existing building in Mediterranean area, and to quantify the potential contribution provided by retrofitting solutions implying the adoption of green roofs and green façades. Dynamic simulations, validated by comparison with experimental results, show that a green façade with dense foliage allows a reduction by 1.7 °C in the indoor air temperature and by 1.5 °C in the inside surface temperature, if compared to a traditional retrofit solution for the envelope. Furthermore, the outside surface temperature is reduced by 2.9 °C, and the cooling load is reduced by 32%. These results suggest that green façades are a viable solution to mitigate current environmental issues in buildings. Lower energy consumption corresponds to lower pollutants emissions and to economic savings in the use of the building.
The adaptation of the existing building heritage to contemporary quality and performance standards is a current topic always at the center of scientific and cultural debate, especially in a country like Italy r ich in both historical... more
The adaptation of the existing building heritage to contemporary quality and performance standards is a current topic always at the center of scientific and cultural debate, especially in a country like Italy r ich in both historical buildings to be protected and enhanced, and modern buildings that need functional, static and energetic adjustment. One of the most significant aspects concerning the quality of the built environment is the issue of accessibility. In fact, the usability of spaces for all users, without discomfort or impediment, affirms the human right to mobility and it is a sign of civility and respect for the dignity of individuals. In recent years, the concepts of architectural barriers and disabilities have undergone considerable evolution. Therefore, buildings must be designed in terms of accessibility, with an inclusive design approach, even in the case of interventions on the existing ones. In this context, it is essential to know the needs of different users and to translate their requests into real applications for the design of new buildings or for the adaptation of existing ones. In the present research, a methodological procedure is proposed and applied to three buildings and their external areas of the University of Catania, which allowed both to recognize the deficiencies of the built environment through a critical reading of places, and to identify the technical solutions to guarantee the multi-sensory use of spaces.
Over the past 15 years, housing supply for university students has increased significantly given the considerable attention provided by national institutions on the issue of student housing. In Italy, however, only approximately 4% of... more
Over the past 15 years, housing supply for university students has increased significantly given the considerable attention provided by national institutions on the issue of student housing. In Italy, however, only approximately 4% of students live in university residences. Since 2001, interventions on existing buildings have accounted for approximately 60% of the overall measures proposed for new university residences; these interventions comprise most of the available public economic resources. The possibility of recovering and reusing existing buildings for university residences is remarkable for the city of Catania because most of the students are enrolled in university courses located within the historic city center. Moreover, abandoned buildings are currently a significant part of the city׳s architectural heritage. This research aims to develop an articulated and integrated set of frameworks to support the various phases of the design process for recovering and then reusing existing buildings as university residences. The proposed approach applies existing dimensional standards and environmental sustainability principles to a constructed building using traditional techniques.
Green roofs present a viable solution for increasing rainwater retention while improving the energy performance of both new and existing buildings. Considering the widespread occurrence of existing buildings, it is worthwhile to conduct... more
Green roofs present a viable solution for increasing rainwater retention while improving the energy performance of both new and existing buildings. Considering the widespread occurrence of existing buildings, it is worthwhile to conduct an in-depth analysis of green roof feasibility for retrofitting these buildings. In such cases, the first constraint is related to structural compatibility. Therefore, the use of lightweight systems should be prioritized to minimize overloading of the existing roof. Another possible constraint concerns the viability of green roofs. The main advantages of green roofs are their energy savings and environmental benefits. In this study, different green roof solutions were evaluated and their performance was compared against the findings of previous studies. The analysis was carried out in the Mediterranean city of Catania, and the results show that only green roof solutions with a load limit of 1.46 kN/m 2 are suitable for retrofitting existing buildings. As regards the energy savings, energy consumption for cooling was reduced by 31–35%, and during winter, energy consumption for heating decreased by 2–10%. The environmental benefits were quantified during summer and compared to those of non-vegetated roofs. The results show removals of 1.35 kg m-2 ·y −1 of CO 2 and 0.03 kg m-2 ·y −1 of NO 2. Finally, the economic analysis indicates that the discounted payback time of the investment varies from 13 to 18 years depending on the substrates and vegetation used on the green roof.
Research Interests: Green Infrastructure, Green architecture, Green Construction, Green Building, Green Technology, and 9 moreGreen Architecture and Environmental Design, Green Roof, Energy Efficient Retrofitting, Green Roofs, Retrofit, Green Roof Technology, Retrofitting, Green Roof System, and Sustainable retrofit of existing buildings
In the current global context, where building management is responsible for a large part of global energy consumption, environmental mitigation and reduction in greenhouse gas emissions are increasingly needed to counteract the risk of... more
In the current global context, where building management is responsible for a large part of global energy consumption, environmental mitigation and reduction in greenhouse gas emissions are increasingly needed to counteract the risk of climate change. Environmental issues and the resulting regulations lead to research in the field of building applications towards the use of more sustainable and eco-friendly materials. Wood and wood-based products have characteristics that make them in line with the new environmental perspective. Wood has played a significant role in the building industry in all the historical epochs and, according to the geographic, climatic, economic and cultural context, its use has always been reinterpreted in different ways. Currently, the most widespread wood construction systems, such as the Cross Laminated Timber (XLAM) or the Platform Frame, are based on a high degree of factory prefabrication, enabling rapid assembling of the panels on site with a consequent reduction in construction times. To make wood a sustainable and eco-friendly constructive material, rational use of resources, proper forest management, use of non-toxic adhesives and solvents, and appropriate assembly methods are required. Furthermore, wood systems guarantee excellent seismic behavior due to their lightness and to the high ductility of well-designed metal connections. Into the stratigraphy of sustainable wood buildings, high energy efficiency performance can be achieved by pointing out to both low thermal conductivity and use of natural insulating instead of synthetic ones. In this paper, after analyzing the characteristics required to wooden system, a technical solution based on the Platform Frame is proposed, including high-density pressed straw elements in the internal gap. The use of natural insulants from appropriately processed agricultural waste can be a solution to improve both the energy performance of building envelope and the sustainability. In addition, the use of economic materials with low primary energy is one of the strategies in order to mitigate the environmental impacts of building sector.
Research Interests:
In recent years there have been considerable improvements in the energy and environmental performance of buildings, due not only to the creation of building envelopes with a low level of thermal transmittance but also to the use of... more
In recent years there have been considerable improvements in the energy and environmental performance of buildings, due not only to the creation of building envelopes with a low level of thermal transmittance but also to the use of natural (“green”) materials. Construction systems combining a wooden framework with eco-compatible materials represent solutions for a building envelope, which prove effective in reducing both energy needs and the discharge of polluting substances. The principal aim of the present research is to investigate the use of natural waste materials from farm products in the creation of building envelopes. The system described here proposes the use of compressed straw to obtain a layer of insulating material, that may be combined with the use of a wooden shell known as platform frame. The thermo-physical characteristics, energy performance as well as the hygrometric features of the proposed system were tested in various sites. As regard the formation of condensation, the thermo-hygrometric analysis proved the absence of such threat over a period of a whole year in all the different climates observed. A comparison with a similar XLAM system evidenced that the platform frame system lined internally with compressed straw offers a 12% reduction in U thermal transmittance, a 22% improvement in YIE periodic thermal transmittance, and a comparable thermal lag. Moreover, the platform frame system filled with compressed straw allows a cost reduction by 38% compared to the XLAM system. On the whole, the outcomes obtained indicate that the platform frame system with compressed straw offers a suitable alternative to the XLAM system, above all in the case of buildings of two or three stories.
Research Interests:
Green roofs are technical solutions that are increasingly adopted to improve the quality of the urban environment. The major benefits are the improvement of the thermal performance of the building envelope, the reduction of risks related... more
Green roofs are technical solutions that are increasingly adopted to improve the quality of the urban environment. The major benefits are the improvement of the thermal performance of the building envelope, the reduction of risks related to rainwater fall and the subtraction of CO2 from the atmosphere. To improve the energy performance of existing buildings, the retrofit with green roof is an effective solution, but it is mandatory to carefully consider their compatibility with pre-existing structures due to the additional loads. This article through dynamic thermal simulation evaluates the magnitude of energy savings originating by the use of two different types of green roofs applied on the flat roof of a multi-storey residential building. The conducted simulations allow to calculate, for the two different layers of vegetation used, sage or sedum, the outer surface temperatures of the roof and the indoor surface temperatures of the local positioned under the green roof. Moreover, the annual energy consumptions spent for space heating and cooling are evaluated. Through the data obtained, the improvement of the energy performance of the cover is evident for both the layers of vegetation used. To test the different effectiveness of green roof retrofit, the same simulations are developed at different latitudes representing different European climates, particularly in Catania, Amsterdam and Stockholm. Finally, it is determined whether green roof is cost-effective and how many years are necessary to recover the investment. The economic analysis proves to be quite costly and involves a long payback period despite the tax breaks. However, looking beyond the merely economic interests of the investing private, the retrofit of buildings through green roof maintains its attractiveness considering the improvement of the environmental quality, with positive implications for the whole community.
Our cities possess a vast heritage of buildings, many of which are in a severely degraded condition, falling short of current standards of energy efficiency and technological performance. As European examples have shown, by integrating... more
Our cities possess a vast heritage of buildings, many of which are in a severely degraded condition, falling short of current standards of energy efficiency and technological performance. As European examples have shown, by integrating the transformation of these buildings with a reorganization of the urban spaces it is possible to regenerate entire areas, improving the standard of living of inhabitants and paving the way to a more sustainable future for the city. This study focuses on a sustainable redevelopment of the San Leone area of Ca-tania, consisting prevalently of low-cost residential blocks constructed between 1950 and 1970. The redevelopment project was preceded by a phase of historic and documental investigation, including analysis and listing of all the existing buildings. The approach adopted in the design phase was on two levels: the single buildings, to improve the technological performance of each for an esthetic and functional retrofitting; and the area, to achieve a general improvement in the standard of living. The desire to bring the buildings up to present standards of well-being and safety, combining technological and esthetic requirements, has led to a project based on bioclimatic criteria, to ensure protection against excessive solar radiation and guarantee the heating and natural ventilation of the rooms, an improvement in the thermal characteristics of the envelope and the use of renewable energy sources. The urban regeneration of the area follows four directions: increase in the quantity and quality of the green areas; improvement in drainage of the ground; coordination of the systems for collecting rainwater; recovery of the Acquicella riverbed through water management and sustainable wastewater treatment. The studies show the concrete feasibility of redeveloping neighbourhoods of low-cost buildings with a view to reaching a high level of global quality. The interventions proposed allow for a notable improvement in energy efficiency, together with a reduction in both consumption and CO2 emission. The overall result is a saving in economic terms sufficient to offset the costs of retrofitting over a short period of time.
Historically, the temporary and transportable dwellings, in particular those can be dismantled and reassembled, have represented the best solution to deal with the emergency situations, due to their functional autonomy, velocity of... more
Historically, the temporary and transportable dwellings, in particular those can be dismantled and reassembled, have represented the best solution to deal with the emergency situations, due to their functional autonomy, velocity of construction , possibility of recovery and ability to adapt to different environmental and territorial situations. Since ancient times different population have developed-depending on the place's characteristics and their customs-temporary and transportable shelters, using the available restricted resources to produce functional and safe refuges. The interest to different type of constructions, characterized by their provisional nature, date back to Palaeolithic Age, which during this period nomadic population used provisional shelters such as Aurignacian huts, built with a self-supporting frame of branches recovered by heavy tents. Over the years, different solutions with increasing structural and thermal-hygrometric performances, have led to the evolution of provisional and/or transportable structures, with consequent increment of technical characteristics. In particular, with industrial revolution-from which are highlighted some events such as the high request of accommodation for averages , the colonial housing and the military emergency-themes regarding to structures that can be dismantled and transported and flexible spaces have been dealt. Through an historical overview-which begins from the first provisional shelters, passes through the emergency housing of nineteenth and twentieth century and arrives to current experimentations in the reference environment-the present work aims to produce a full framework about steps that have led to current idea of dwelling for emergency, that through its functional characteristics allow to solve, on short time and with limited cost, the problem of housing in post-seismic phase.
Considering that most of Italy was classified as seismic with technical standards emanated from 1981 on, more than 50% of the existing buildings were designed and realized without considering seismic actions as one of the possible loads... more
Considering that most of Italy was classified as seismic with technical standards emanated from 1981 on, more than 50% of the existing buildings were designed and realized without considering seismic actions as one of the possible loads acting on them. All these buildings are therefore in need of structural improvements in order to withstand the forces due to the earthquakes; moreover, many of them present technical and construction characteristics unsuitable for the surrounding climatic conditions, resulting in excessive energy consumption. In this context, one of the most common types of building to be found throughout the territory is represented by multi-storey buildings with a load-bearing structure in reinforced concrete; the design of these was approved both before the seismic classification of Italy and prior to the laws limiting energy consumption. Over the last few decades interest has grown in the improvement of energy efficiency. However, many interventions for energy efficiency have not improved the structural performance of buildings. The present study may be considered within the wide context of research about the retrofitting of existing buildings, in the quest for a solution to integrate structural, energetic and architectural retrofitting of multi-storey buildings in reinforced concrete constructed before the early nineteen-eighties. The study aims to provide a ventilated facade system enclosing a series of buckling restrained braces, to combine the advantages in terms of improved energy efficiency and comfort deriving from the ventilated facade with a structural improvement due to the use of buckling restrained braces. To this end, the work studies the technical and construction interaction between the ventilated facade and the buckling restrained braces connected to the outer surface of the reinforced concrete load-bearing structure of the building.
The most suitable intervention for energy rehabilitation of historical buildings has to reach both the goal of the optimization of the energy saving and the preservation of the original characteristics of the building. The possibility of... more
The most suitable intervention for energy rehabilitation of historical buildings has to reach both the goal of the optimization of the energy saving and the preservation of the original characteristics of the building. The possibility of restoring these historic buildings, re-utilizing them for a different purpose, and requalifying them with a view to reducing energy consumption, is an interesting issue for the city of Catania (Italy), if we consider that the abandoned buildings in the city centre currently represent a significant part of the architectural heritage. The method of intervention proposed to give abandoned historic buildings a new energy-saving efficiency was applied to a building in the Old Town of Catania which had served until the early nineteen-eighties as a foundry for the realization of works in cast iron. The interventions to be carried out on the building envelope are designed to meet the requirements connected with the new destination of the building. The strategies employed aim to adopt technological solutions in perfect harmony with the new requirements and to regulate the thermo-hygrometric conditions of the elements comprising the outer walls in order to respect the transmittance limits established by the current energy-saving laws. The final result of the study aims to supply indications which, taking into account the individual characteristics of the different cases studied, may be repeated within the same context, both at a local district level and at that of the entire historic centre, whenever a common matrix may be discovered for the environmental characteristics, the construction techniques and the materials used
The present work is part of the broad research theme on the design of the components of the building vertical closures for large buildings. Between the different types of building vertical closures, in the present work the curtain wall... more
The present work is part of the broad research theme on the design of the components of the building vertical closures for large buildings. Between the different types of building vertical closures, in the present work the curtain wall system, whose performance depends on design choices and on quality of the workmanship in the building site, is taken into account. Among the curtain wall systems, the most efficient is the unitized system which allows in-house component assembly and the related quality controls, reduction of costs and installation time and elimination of works carried out from outside the building. This research aims to identify a construction system combining the high quality typical of unitized façade units with the wide design freedom request to the envelope of large buildings, while meeting its requirements of energy efficiency, acoustic insulation, fire resistance, resistance to weather agents and low maintenance. To this end, in this paper the design of a high-rise building to be constructed in the United Arab Emirates is taken into account where, due to the specificity of its geometry, different types of unitized façade are used.
By comparing the data provided by the Eurostudent Report on the student living conditions in Europe it emerges that Italy ranks near the bottom as regards the number of accommodation places in residences for university students. Indeed,... more
By comparing the data provided by the Eurostudent Report on the student living conditions in Europe it emerges that Italy ranks near the bottom as regards the number of accommodation places in residences for university students. Indeed, although a much higher demand, in Italy only about 4% of students live in university residences. The housing condition of non-resident students enrolled at the University of Catania falls within that general reference framework. In the academic year 2014-2015, the Organization for the Right to University Study in Sicily (ERSU) offered housing services making available 698 beds for non-resident students enrolled at the University of Catania in view of the 1.754 students who were eligible, satisfying only the 39% of them. If we consider that more of 50.000 students are enrolled at the University of Catania, estimating that at least 35% of them are non-resident students, we can consider that about 19.000 students are forced to turn to private market of rental accommodation. The town of Catania must increase the number and the quality of housing supply for university students, conceiving open structures over the city and offering multiple and flexible services, able to respond to the students housing needs. New structures should be inserted effectively in the urban space, in pleasant environmental contexts and at the same time lively and dynamic, connected through soft mobility to the university spaces of teaching and research activities. The objective of the present research concerns the identification of areas where results favourable to locate the university residences and services, starting from the available areas and/or disused buildings to recover within the urban area near the main locations of the teaching and research activities of the University of Catania. To this aim, a software GIS was used which provided a classification of the areas and/or disused buildings and allowed to identify the most suitable location for new university residences. One of the selected areas is located in the San Domenico quarter, in a consolidated urban and saturated context by the city planning point of view. Among the disused buildings located in that area it was concluded that those before utilized as cinemas represent the building category best suited to be transformed in university residence. As case study, the recovery and rehabilitation of the cinema Minerva was proposed, focusing attention on collective functions to establish, in order to make the university residence open towards the urban environment.
The presence of large disused buildings, often very numerous also within the historic town centres and not always of considerable architectural value, is a common characteristic of many Italian towns. The final aim of the research regards... more
The presence of large disused buildings, often very numerous also within the historic town centres and not always of considerable architectural value, is a common characteristic of many Italian towns. The final aim of the research regards the development of a methodology of intervention relating to the sustainable recovery and reuse of disused urban non-residential buildings to allocate university residences. This method provides the identification of the requirements and performance, in terms of accessibility, safety, comfort and sustainability, that the buildings should ensure for their reuse. A first application of this method referred to a building realized with traditional construction techniques, already destined to cinema, located in a district next the historical centre of Catania, which is proposed to reuse as university residence through the design of rehabilitation interventions. The proposed approach applies dimensional standard for university residences and environmental sustainability principles focussing on the integration between functional recovery of the building and improvement of its energy performance and static safety.
Nell'ambito del dibattito sullo sviluppo sostenibile delle città, un ruolo specifico spetta al tema del recupero e riuso degli edifici urbani non più in uso. Il lavoro proposto illustra il progetto di recupero e rifunzionalizzazione come... more
Nell'ambito del dibattito sullo sviluppo sostenibile delle città, un ruolo specifico spetta al tema del recupero e riuso degli edifici urbani non più in uso. Il lavoro proposto illustra il progetto di recupero e rifunzionalizzazione come residenza universitaria di un edificio dismesso, realizzato con tecniche co-struttive tradizionali, già destinato a cinematografo e ubicato ai margini del centro storico della città di Catania. Dopo una prima fase conoscitiva a livello storico e tecnico-costruttivo e sullo stato di conservazione, vengono individuati i requisiti e le prestazioni in ter-mini di sicurezza, accessibilità e comfort che l'edificio dovrà garantire ai fini del suo riuso, nel rispetto dei principi di facile reversibilità delle soluzioni tecnologiche e di massima flessibilità funzionale, riservando particolare attenzione ai valori costruttivi e formali dell'involucro edilizio originario.
The Monograph deals with the study of different green roof configurations by varying the materials used, in order to propose an innovative technological solution. In addition, this Monograph aims to increase the scientific knowledge on... more
The Monograph deals with the study of different green roof configurations by varying the materials used, in order to propose an innovative technological solution. In addition, this Monograph aims to increase the scientific knowledge on building passive cooling, which is one of the main benefits of green roofs. Firstly, a thorough bibliographical survey was carried out concerning the technological aspects in green roofs. The numerical analysis involved the performance of different commercial solutions, in order to identify those with the highest energy performance, even in the case of building retrofitting. Based on scientific literature and numerical analysis results, two experimental set-ups have been designed and installed. The first, built at the University of Catania, aimed to determine the thermal performance of an innovative technology that involved the polyethylene granule, coming from the regeneration of films released in agriculture, as drainage material. The second, built at the University of Lleida (Spain), had the objective of assessing the passive cooling due to evapotranspirative phenomena of green roof, varying the irrigation regime, and correlating it both to the energy performance and the microclimatic conditions.