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O Parque Nacional da Gorongosa foi criado em 1960 e possui 4.067 km2 que integra a Serra da Gorongosa, sendo que em 2008 foi estabelecida uma Parceria Público-Privada de 20 anos para a gestão conjunta do PNG entre o Governo de Moçambique e a Fundação Carr (EUA). O projeto do Parque envolve ainda as comunidades locais que vivem próximas ao parque natural. Este trabalho consiste num trabalho efetivo de caracterização das habitações tradicionais locais e dos modos de construir existentes no parque. Importa perceber as soluções utilizadas, compreendendo o seu funcionamento no que respeita à relação com o clima local, assim como com a resistência e durabilidade das habitações. O objetivo principal consiste na identificação e caracterização dos sistemas construtivos aplicados em 3 aldeias do Parque Nacional da Gorongosa. Pretende-se que esta caracterização seja construtiva, do ponto de vista dos materiais e soluções aplicadas, assim como mecânica através da caracterização em termos da sua resistência e composição. Ao mesmo tempo, pretende-se dentro das soluções construtivas mais utilizadas nas aldeias em estudo averiguar a sustentabilidade, aplicando uma metodologia de avaliação relativa da sustentabilidade. De facto, em Moçambique são recorrentes as construções com terra, a tecnologia mais usual é a terra de recobrimento, apesar do preconceito em relação a este tipo de construções associadas à pobreza o que provoca o seu desprezado pela sociedade. Desta forma, é necessária uma conscientização da população para a execução deste tipo de construções como forma alternativa para a melhoria das condições de habitabilidade da população. Partindo duma matéria prima considerada frágil e caracterizando os materiais que servem de base para o presente estudo, demonstra-se as qualidades e a sustentabilidade dos referidos materiais para a aplicação nas construções de baixo custo e possibilitando assim acesso à construção ultrapassando o difícil acesso dos materiais.

The Portuguese architecture is borderless due to the colonialism period. Many African countries can testify this influence and the cities still sprawling around remaining old buildings. These constructions are characterized by using local resources and adapting Portuguese architecture to the climatic characteristics and answering local natural hazards. The work developed presents a systematic approach about the constructive changes, identifying the solutions adopted for answering climatic demands. The passive solar systems used were categorized and some examples were selected according to examples found in African cities with Portuguese influence as Beira (Mozambique), Lubango, Namibe and Luanda (Angola) and Praia (Cape Verde). This analysis encompasses strategies to improve thermal behavior of buildings, as ventilation trough the analysis of ventilated roofs or windows geometry, shadowing devices as large eaves, brises and second facades, among other issues. The local construction was also analyzed in order to find out traditional techniques for cooling buildings in a natural way.

The energetic certification system was implemented in Portugal in 2006, with repercussion after 2008, and motivated by the transposition of European Energy Performance Building Directive (EPBD) from 2002. The system was reviewed in 2013, after the EPBD recast in 2010. The new legislation came up with restrictive parameters in terms of constructive solutions in order to decrease the energetic consume and Greenhouse Gas Emissions (GGE) from built environment. These parameters, such as U-values for example, are presented through reference and maximum values, and is mandatory that the analyzed building present a nominal cooling and heating needs inferior than a reference building. The thermal code is not mandatory for some buildings, considering some specific characteristics, and are an exception to the norm. It is possible not to apply it in the situation when the code compromises traditional buildings in terms of architectural value and/or patrimonial interest. The aim of this work focused on the analysis of some interventions, the existent solutions and the intervention actions, in old buildings where the thermal code was not applied. These data were compared with the thermal code exigencies in order to understand what extra efforts are required in order to accomplish the reference values and its implications in buildings architectural characteristics as well as its impact in patrimonial relevance and value.

A comparative study was organised in the scope of a recently finished master’s dissertation between three European country’s legal frames: France, Spain and Portugal paying special attention to the Portuguese case. The results of the three studies were compared in order to identify the potential of each regulation in terms of the building’s energetic efficiency whose conception is based on solar passive parameter application. Some of the improvements that were applied are not clearly shown in the results, namely inertia increase (using other solutions and calculus methodology) and different solar orientation. Because of this, a tool for energetic efficiency evaluation of housing buildings is presented that takes into consideration it’s constructive solutions and local climatic characteristics. The results taken were evaluated according to passive solar parameters, for example, thermal inertia and storage specific capacity in relation to the constructive elements. The insignificant impact on results caused by the improvements mentioned implies the need of implementing an evaluation methodology for building’s passive solar performance capable to qualify them in line with the existing regulatory application that leads to the existence of minimum values granting acceptable comfort conditions and energy consumption. This proposed methodology, according to a qualitative analysis of several parameters classified according to pre-established qualitative levels, becomes, in fact, an available tool for the buyer’s choice and an argument to the seller or investor. This paper describes briefly the main aspects of the thermal regulation referred above and, then, it presents and discusses the proposed methodology for the qualitative evaluation of passive solar performance of buildings.

This work enhances the application of a clear and concise methodology to help choosing the most accurate passive solar techniques according to local climate and its influence on construction. To carry out these goals, the analysis of concepts of fictitious temperatures, the psicrometric diagram and its relation to passive solar systems zones previously established and, finally, the constructive changes that each technique requires is needed. This last factor mentioned took into account the technological and scientific knowledge, as well as the current constructive solutions applicable in the building construction sector in Portugal. The article clears these questions from the design point of view, establishing a straight interdependence between theoretic concepts and its practical application, framed by a context of optimisation, adopting the Portuguese traditional construction as the experimental scenario.

To achieve a sustainable building’s behaviour and preserve the environmental balance, three laws must be taken into account: (i) the resources’ consume must not be faster than the rate at which nature can restock them, (ii) the creation of systems that consume maximum energy-quality and (iii) the maximization of the use of renewable and recycled materials. Therefore, the buildings’ rehabilitation process must increase, instead of the proliferation of new buildings, in order to provide the sustainability of the built environment and minimize its ecological impact. The sustainable rehabilitation process is even more difficult in historical areas, in general sited in central zones of the urban mesh, with fragile comfort conditions and a rigid structure. In this paper, different evaluation tools for sustainable buildings were analysed in order to provide a set of evaluation criteria to be applied in the rehabilitation process in historical zones.

The energy consumption of buildings has presented a steady growth in face of the global energy consumption. This fact is related to a variety of factors, including the increased demand for comfort by the inhabitants, the low quality of construction of buildings and their inadequacy to the climatic and environmental context in which they are included. Reversing this tendency includes the necessary intervention in the built environment, promoting the attainment of comfort through interventions that respect the principles of sustainability in construction, namely in resource consumption over the building’s life cycle. Energy rehabilitation can be accomplished by enhancing the envelope’s thermal protection using strategies in terms of i) strengthening insulation in the opaque envelope; ii) strengthening insulation of the glazing and iii) control of solar gains. The use of passive solar systems and the improvement of energy systems are other approaches for improving the thermal performance of dwellings. This study examines the constructive characteristics and the pathologies found in approximately 700 buildings located in Coimbra’s downtown (“Baixa”), the historic sector of the city. From this analysis it was possible to assess the present-day performance of these buildings, attending to the existing code and the application of DesignBuilder software, and to define the desired levels of performance resulting from rehabilitation procedures. The definition of these levels allows the superintendence of the process of intervention, taking into account the solutions to adopt with regard to the principles of sustainability.

Different sustainable evaluation tools can provide a way to certify the building¬¬`s performance during its life cycle: raw material depletion, production of materials and components, construction, use and demolition. In this process, several variables that analyze common components, such as the reduction of resources consume, the reuse and recycle potential, flexibility and adaptability, the pollution components generated during the process, are involved. Some examples of these tools are the systems like SBTool, BREEAM, BEE or LiderA that are used to evaluate a specific context according to specific conditions. Meanwhile, the existing evaluation systems are oriented to the building´s design phase or have under consideration patterns adapted to the 21st century reality. This work was developed due to the need to analyse and evaluate the built environment, specifically in what concerns the urban settlements in Portuguese cities, with more than three hundred years old, and that are not enclosed in the new construction’s reality - both at materials and techniques levels. The knowledge gathered about the built environment allows the creation of a sustainable grid capable of guide-lining rehabilitation actions. The evaluation of these urban areas was carried out based on an exhaustive work of collecting the building’s characteristics, in an area with around 770 buildings, allowing the creation of a built environment sustainability evaluation grid and adapted to socio, cultural, heritage, economic and environmental contexts. The grid mentioned before was designed after a set of parameters were analyzed, such as: i) the existent materials and the constructive solutions adopted; ii) the urban mesh and the meeting of the construction resources to the built environment; iii) the contemporaneous patterns and the possibilities of reusing; iv) the heritage and cultural values; v) the social and economic values. The evaluation grid presented in this work shows a set of different parameters, where the criteria that are related to the external environment are reassessed according to the existent urban possibilities and where the criteria related to internal environment are adapted to the existent spaces’ possibilities.

Natural ventilation as a part of a buildinǵs function that has a strong effect on human comfort. The reduction of natural ventilation and infiltration, as a part of the ventilation system in the old existing buildings, due to intervention actions, have been causing a reduction in indoor air quality and an increment of relative humidity levels in the indoor environment. Providing optimal indoor condition is not only related to the renewal of the air but also with its distribution. Hence airflow patterns in historical buildings influence interior comfort conditions. The aim of this work is to assess the effectiveness of the existing natural ventilation system in the old and historical buildings by different natural ventilation strategies. To achieve the proposed objective, the research was developed resorting to in-situ measurements and simulation methods The simulation was performed with the Design-Builder software and the main goal was answering to the following question: - What are the existing conditions of the building in concern of the airflow circulation and distribution? The in-situ measurements were performed using Blower Door Test method in order to determine the existing building airtightness. Based on the obtained results for each building the intention is answering the following question: - Due to the limitation of the historical urban areas, which natural ventilation strategy is more effective? The results of this research can be interesting for architects, engineers, and people, who are working on intervention and renovation of old existing buildings.

It is currently recognized that the residential building sector is one of the largest energy consumers in the world. The energy crisis of the 1970s was important for drawing attention to the subject of energy consumption and the necessity to save energy. The airtightness of buildings is an important factor affecting a building’s energy consumption and also energy-saving potential. On the other hand, the ventilation rate has also a significant effect on indoor air quality and is assumed to be an essential criterion of a building’s performance. However, most of the existing research in this area has been developed in cold climates and there is a research gap with regard to countries in warmer climates such as those close to the Mediterranean Sea. Therefore, this research aimed to study the airtightness and ventilation rate of existing buildings by employing in-situ measurements. In-situ measurements were achieved using the fan pressurization test (Blower Door Test) method. According to the selected case studies, the results of the measurements indicate a correlation between building typology, airtightness, and ventilation rate.

The constructive particularities of Portuguese old buildings, with specific and ancient constructive solutions and buildings’ aesthetics, determine the type of interventions and turn some of the most efficient interventions impossible to apply. Since the external appearance of buildings in old city centers must be preserved, nor is the use of external isolation not an alternative, neither the use of materials with low hygro-scopicity, due to the nature of the material used in exterior walls, usually stone. Presented research was expanded to figure out the reaction of different intervention solutions which are used in old buildings’ envelope to accomplish their energy performance. The old city center of Coimbra has a building typology very characteristic and similar to other Old Portuguese city centers, so the idea was to create a representative building of their dimensional characteristics. The modeled building unit was designed after studying around thirty buildings. With all the collected data, it was possible to design a building which we consider that as representative of Coimbra City Centre buildings. This modelled building was used to simulate, with Design Builder software, in real condition and with different solutions for interventions in facades, to predicting the thermal performance achieved for each one. Their final performance was analyzed and compared. The achieved results will be used to define the most suitable interventions in old buildings to improve its energy performance beside of good indoor air quality.

Building airtightness assumes an important role in the energy saving and the indoor thermal comfort. Ventilation rates bring significant impacts on energy usage in the constructions and indoor contaminant concentrations and also setting them as the key parameters in building performance. Ventilation rate have been measured in building for a long time, and there are some developed measurement methodologies related to it in the research domains. However, most of the investigations in recent years have been done usually in the cold climate conditions, while Mediterranean construction are not deeply investigated in the literature. In this paper, the authors present the obtained results of an experimental research which is carried out on the Portuguese residential buildings. The investigation is done by fan pressurization methods, also known as “Blower Door Test (BDT)” as the measurement method as well as Design Builder (DB) as the simulation software. The airtightness measurement of the existing buildings and the influence of air leakage on energy consumption and indoor comfort in different Portuguese construction typologies are focused on the aim of the research. The important parameters of the building such as whole-building air change rates, building infiltration rates, and ventilation effectiveness rate in the residential building are also considered in this research.

It is essential that the society understands the importance of sustainable development, its implication for the existing living standards and the need to implement management policies that promote sustainability. Rehabilitation assumes a fundamental role in this process; however, we are faced with the lack of specific, adequate and simplified tools for the sustainability assessment in rehabilitation actions. In this paper, the analysis of different sustainability assessment systems was conducted, comparing them in order to identify the adjustments to be made to a Portuguese model taken under consideration. Subsequently, the model was cross-checked with current European and national urban rehabilitation and regeneration policies, analysing their contribution to sustainability, in order to define the assessment criteria and create a Simplified Method for the Sustainability Assessment for rehabilitation in old urban centres, which can be a useful tool, easy to use by all actors in the process and as a way of preserving the history of this areas, and the memory of those who inhabit them. This Method considers five major areas: Water, Energy, Materials, Emissions and Cultural, Economic and Social Environments. For each of these criteria, measurement indicators and levels of assessment were settled, adjusted to the context of old urban centres.

A Santa Casa da Misericórdia de Castelo Branco possui um conjunto de edifícios contruídos entre 1526 e 2008, sendo atualmente utilizados como creche, asilo de idosos e centro de reabilitação médica. Tanto o ano de construção, como as diversas intervenções realizadas, traduzem-se na diversidade de soluções que se podem encontrar, dentro do mesmo edifício ou entre construções. Este trabalho teve como objetivo identificar a variedade de soluções construtivas existentes e analisar o nível de conforto dos utentes nos edifícios ocupados como lar de idosos. Foram desenhados inquéritos de conforto térmico, aplicados através de entrevista para garantir o seu entendimento pelos idosos, utilizando a escala ASHRAE, sendo os resultados comparados às soluções encontradas (algumas identificadas a partir de ensaios). Com os resultados foi possível identificar os espaços com maior necessidade de intervenção devido à percentagem de insatisfeitos, permitindo que as ações de reabilitação possam ser programadas e realizadas de forma faseada de acordo com as necessidades e disponibilidade financeira da instituição.

Recovering old urban centres is a Portuguese strategy to promote development and economic growth, supported by the strong evolution in the tourism sector that has been revealed as a key element for increasing gross domestic product (GPB). The Europe has also a specific worry in which built environment is concerned, namely through the European goals until 2020 that are based on the need to reduce the energetic consume and to increase the use of renewable resources. Having in mind these aspects, in this paper the following tasks were done: i) sustainable assessment tools for rehabilitation actions were analysed; ii) European and national policies for urban rehabilitation and renewal were studied, in deeper sense, the one towards sustainability; iii) to create a simplified model to assess sustainability in old city centres interventions, criteria were defined; iv) a model was designed with areas, criteria and assessment indicators. The model presented is accurate with the built environment and its application makes possible to assess the impact of solutions, systems and techniques adopted in the design process, with the analysis of the defined criteria and the aim of improving the environmental, social and economic performances of buildings and old urban centres.

A taxa de renovação de ar de um edifício desempenha um papel importante na eficiência energética e no conforto térmico interior dos edifícios. Diferentes características do edifício como idade, altura, localização e tipologia têm influência direta ou indireta sobre a taxa de renovação. Existem já diversos estudos desenvolvidos, neste campo, nos EUA e no norte da Europa, especialmente sob condições climáticas frias, mas os edifícios do Mediterrâneo não têm sido alvo de muita atenção. Assim, este trabalho pretende apresentar uma investigação realizada sobre a correlação entre a taxa de renovação de ar de um edifício e a sua tipologia e altura, em Portugal. Blower Door Test (BDT) foi o método selecionado como metodologia de estudo. Com este objetivo foram efetuadas medições in-situ em edifícios residenciais no Centro Histórico da cidade de Coimbra, Portugal. Os resultados obtidos foram comparados com os valores permitidos na regulamentação Portuguesa. Finalmente e com base nos resultados experimentais e da regulamentação algumas conclusões foram puderam ser retiradas: -Existe uma relação linear entre a altura dos edifícios e a taxa de infiltração. -A taxa de renovação de ar de um edifício multifamiliar é superior de um edifício unifamiliar.

In this paper it was analysed the evolution of the Portuguese Thermal Code in of face of sustainable parameters. The two versions were applied to the same housing building in two different positions in a way to improve the solar gains and be able to compare the results. The results gotten from the former steps were analysed, as well as the main differences noted between the two versions of the Codes. The calculus method pursued in the second version is similar to the first one, due to the technicians applying familiarity, but inserting new parameters and more demanding values. Considering that the new construction exigencies, highly concerned with sustainable constructive principles and environment-responsive attitudes, a set of the main factors to take under consideration in face of the more recognized sustainable construction methodologies is presented. The final stages of the paper focus the assessment of the collected results of the two versions of the Code, relating them with the sustainable construction criteria. These parameters allow outlining an overview about the Code evolution and its contribution to the improvement of the housing sector, in terms of the sustainable development.

The paper presents a methodology of evaluation of buildings’ solar passive performance. This methodology was developed in agreement with quality levels for thermal parameters which were chosen according to the construction’s solar passive behaviour and the regulamentary concepts. A comparative study was organised in the context of a recently finished master’s dissertation between the legal frames of three European countries, giving special emphasis to the Portuguese case. The results of this study allowed the conclusion that it has become essential to combine minimum regulation values to methodologies that grant an evaluation and qualification of a building in terms of its thermal performance

The current challenges of sustainable construction are frequently deemed incompatible or hardly reconcilable with the basic principles of heritage safeguarding and conservation. This issue may gradually be surpassed with a thorough integrated analysis of the rehabilitation solutions and a detailed knowledge of the existing building. This paper presents the application of an exploratory model for an integrated evaluation of rehabilitation actions according to different perspectives, such as local regulatory demands as well as sustainable heritage preservation concerns. The design of this approach was based on a constructive characterization and conservation state analysis of three city blocks located in the Historical Centre of the city of Viseu, in Portugal. The main goal was to create a tool that allows the evaluation of rehabilitation solutions according to different criteria, allowing a holistic comparison of its performance. This will allow technicians and decision-makers to perform more informed judgements, contributing to define a more global and sustainable renovation process.

A Estratégia 2020 da Europa define desafios relacionados com a reabilitação do ambiente construído, assumindo a sua importância para o consumo de energia e emissões de gases com efeito estufa. Neste sentido foram definidas diversas políticas, em vários setores da economia, com vista a atingir o objetivo de redução em 20% das emissões, redução em 20% do consumo energético e aumento da produção de energia com recurso a energias renováveis em 20%. A sustentabilidade deve estar alinhada com os objetivos estratégicos e políticos, neste sentido importa incorporar estes objetivos em sistemas de avaliação da sustentabilidade, nomeadamente no setor da reabilitação de edifícios. No âmbito deste trabalho foram analisadas as políticas europeias e portuguesas em relação à reabilitação do parque edificado, identificando as exigências e metas que tenham implicações ao nível do projeto, em alguns casos sendo condicionantes para o acesso a fundos europeus. A partir da identificação das implicações destas políticas nas intervenções, foi definida uma metodologia simplificada de avaliação da sustentabilidade na reabilitação, com a definição de critérios de avaliação. Estes critérios incorporam as exigências das políticas, revelando-se uma ferramenta que responde, não só às exigências de qualidade ambiental, social e económica dos edifícios, mas também as prioridades políticas de âmbito nacional.