Civil and Architecture and GeoResources

This paper proposes a method to aid in the comparison and choice of alternatives for assemblies closely related to buildings’ thermal performance. The method provides an assessment of the environmental, energy and economic life cycle from cradle-to-cradle (3E-C2C) following recent European Standards for the environmental and economic assessment of construction works. Environmental performance is assessed using life cycle assessment method, energy performance corresponds to consumption of energy for heating and cooling, and the economic performance is based on the whole-life costing (WLC) method.

The 3E cost-C2C approach establishes weights that allow the quantification of each aspect of the assembly's performance using the same unit. This approach uses a prevention-based environmental impact assessment method that converts the results of all impact categories into an economic unit. This allows the cost of the environmental impacts to be added to the economic and energy WLC and a 3E performance C2C to be considered, therefore preventing contradictory conclusions that can arise from the individual analysis of each aspect.

3E-C2C is useful in the selection of an external wall alternative, and corresponding insulation thickness, when comparing alternatives that are not functionally equivalent, since there is no need to change their characteristics to make them comparable.

Este livro sobre imobiliário sustentável aborda uma temática da maior atualidade, nomeadamente a sustentabilidade na promoção e gestão imobiliária do edificado. O livro inicia-se com uma reflexão oportuna, sobre a mudança de paradigma hoje em curso no mercado imobiliário, o autor leva-nos às ultimas reflexões sobre as tendências existentes interligando-a às principais questões ambientais. Lança-se assim o desafio do imobiliário sustentável, com uma proposta de uma grelha de análise abrangendo a promoção, planeamento e projeto até à locação, bem como regras de orientação para a procura de um ambiente construído sustentável nessas diferentes fases

Europe is facing one of its most challenging crises since Great Depression and the construction sector is one of the worst affected. Refurbishment is therefore often suggested as one of the most useful solutions for the current real estate crisis in consolidated areas like the EU. On the other hand, it is imperative to construct buildings according to sustainable principles regarding economic, environmental and social issues. Therefore, proper decision-support methods are needed to help designers, investors and policy makers to choose the most sustainable solution for a refurbishment project, especially for energy retrofit works. This paper reviews the works relating to sustainable refurbishment decision-support tools which have already been developed. For this purpose we have analysed and classified 40 different methods, with particular focus on their main common aims. They are also compared with other classifications proposed. This paper further highlights the role of energy as a driving factor and discusses what other research developments are needed to create related tools for the future that could respond to actual construction requirements.

This paper compares the criteria weighting process of four sustainable construction assessment tools: LiderA, SB ToolPT, Code for Sustainable Homes, and LEED for Homes 2012. The actual weights are first discussed in conceptual and numerical terms by benchmarking those in the four tools that have similar criteria. These four tools are then used to assess the sustainability level of a Portuguese residential project, the Palácio dos Condes de Murça (Counts of Murça Palace), to discuss the real influence of the weighting process on the final classification, in a real situation. Based on these two approaches, the work debates how the weighting process can contribute to the quest for passive net zero-energy buildings (NZEBs). In other words, this paper intends to ascertain whether the energy criteria's weighting is singling out bioclimatic principles as a priority for NZEBs. In conclusion, this work showed that the four different weighting sets are robust and generally similar. In fact, the case study analysis demonstrated that the final class is equivalent in the various tools. However, as far as energy is concerned, it is not clear whether the tools are pointing to passive design as the primary answer to achieve efficient NZEBs.