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Climate change is accelerating and can seriously affect the built environment, if not properly acknowledged in the design and maintenance stages. Despite the globally expected warming, climate changes will differ depending on region and climate type. What implications will temperature, precipitation and wind changes have on the degradation of the building envelope, in Southern Europe? How will the performance of façade claddings be affected by the end of the century? The purpose of this research is to determine the expected impact of climate change on the degradation of rendered façades, in a dry and hot summer temperate climate. This study is based on the complex relationship between climate parameters projections for Portugal and the known effects of environmental agents on the degradation of renderings. Projections indicate the increase of mean temperature and heat waves, reduction of precipitation and wet days, intensification of rainfall in shorter periods and decrease of wind speed in most of the country. Notwithstanding the projections’ inherent uncertainty, more cracking and fewer stains are expected. Due to the cracking increase, more loss of adhesion is probable. Further research is necessary to assess the risks of intense rainfall events to rendered façades, considering the also projected precipitation decrease.

The construction sector is a major contributor to global environmental impacts. This is one of the reasons why there is a political trend towards a ?greener? sector. One indicator of this trend is the progressive application of life cycle thinking approaches and life cycle assessment of products, assemblies and buildings. The digitalization of construction projects, namely the use Building Information Modelling (BIM), can constitute a support to the automation of the application of Life Cycle Assessment (LCA) at the building?s design stage. However, besides the complexity of LCA model and results interpretation, BIM models usually lack LCA data that allow environmental impacts calculation. Currently, few publications explicitly relate the integration of LCA and BIM with the specificities of distinct development stages in the design and construction process or Levels of Development (LOD) of BIM objects. This paper summarizes the possible sources of LCA information to include in BIM models and discusses the complexity of LCA information needed for distinct BIM objects? LOD. A parametrization of environmental information is proposed, to be included in BIM objects, based on an evolutionary level of detail in LCA information for increasing LODs., This work was supported by FCT - Fundação para a Ciência e Tecnologia [grant number PD/BD/127850/2016] under the Doctoral Program EcoCoRe - Eco-Construction and Rehabilitation. Support from CERIS and Instituto Superior Técnico is also acknowledged., info:eu-repo/semantics/publishedVersion

According to the predictions of United Nations (2017) there are more than 7 billion people on Earth and this number will reach 9.7 billion by 2050. Today, most of the population lives in the urban areas and the rapid growth entails more construction in a housing sector. Since the industrial revolution the world has experienced countless technological attainments and on the other hand risky increase in natural resources use, energy consumption, greenhouse gases emission, ozone depletion, toxification and global temperature rising. The question how the cities can respond to urban growth is related to the sustainable goals of Agenda 2030. This research discusses potential of the usage of timber as construction material and it also brings the answer to this question. The wood is 100% renewable, recyclable and nontoxic material with capacity to absorb CO2 and perform low embodied energy. The increase of timber use in the construction contributes to sustainable development and to the reduction of waste, CO2 emission, as well as energy consumption. The aim of this paper is to discuss the advantages of using timber as a sustainable solution in urban context, in comparison with most commonly used concrete. The findings demonstrate the value of timber as sustainable construction material.

The use of least-squares regression to probe the level of lead contamination of plaster of Paris standards in the calibration of (109)Cd KXRF systems for bone lead measurement, as well as the use of iteratively reweighted least-squares (IRLS) in the case of violation of the assumptions for ordinary least-squares (OLS), is discussed here. One common violation is non-uniform residual variance, which makes the use of OLS inappropriate due to strong influence of points with large variance on the calibration line and variance of the slope and intercept. Comparison between OLS and IRLS in that case showed that IRLS estimates of the intercept are significantly smaller and more precise than OLS estimates, while a less marked increase in the calibration slope is observed when IRLS is used. Moreover, OLS underestimates bone lead concentrations at low levels of lead exposure and overestimates those concentrations at higher levels. These discrepancies are smaller in magnitude than the measurement uncertainty of conventional systems, except for high concentrations. For the newly developed cloverleaf systems, the suggested differences at bone lead concentrations below 17 ppm are comparable to the minimum detection limit, but are larger than the measurement uncertainty for bone lead concentrations above 60 ppm.