Strategies for green architecture: case studies in Portugal

Abstract

The objective of this research focuses on defining appropriate strategies to accomplish green architecture fulfilling the contemporary expectations of lifestyle yet, maintaining the local identity. The construction systems of exterior walls and horizontal elements of housing buildings in Portugal are generally heavyweight. Although concrete and brick allow high thermal inertia and acoustic insulation, these materials account for almost half of Embodied Carbon (EC). Therefore, in order for sustainable building solutions, materials with lesser EC than brick and concrete should be considered. The combined use of lightweight systems with conventional building materials called mixed-weight systems can be an alternative to achieve low EC with acceptable thermal and acoustic performance as proven in previous studies from the first author. Using less material from sites or lighter systems to control emissions from transport and industrialized materials also promoting recycle and reuse, are a few strategies in the presented three case studies of housing buildings. One such case study is located in Aveiro, a coastal town in the center of Portugal. This case study combines the traditional material from the site – Earth in walls and Wood in horizontal elements, allowing to obtain a Mixed Weight solution with EC. The Angra do Heorísmo case study aims to reinterpret the old haystacks of the farmers, with inspired techniques from old fishermen's huts in Comporta in the Alentejo region of continental Portugal. These huts are built out of cryptomeria wood sourced from the Azores Region. The main objective of this project is to demonstrate the possibility to integrate the old thatched haystacks using vernacular methods to achieve low EE. The last case study is an eco-cabin under construction on Terceira Island. The aim is to test some of the cabin components, and to achieve this a test cell is proposed on the Campus de Azurém of University of Minho, Guimarães.