In Portugal a large number of vernacular earthen buildings present an advanced state of degradation. These buildings comprise historical, technological, architectonic, cultural and social recognized values and, therefore, efficient interventions are needed for their conservation. The knowledge of the properties that the materials used in their construction show nowadays is one of the bases to support future interventions. Unstabilized earthen samples were collected from the walls of six earthen buildings located in the region of Leiria, Portugal, built with rammed earth and/or adobe masonry. The samples were characterized by particle size distribution and through XRD, density, capillary, drying, dry abrasion, tensile and compressive flexural strength. Mechanical results of rammed earth were lower than adobe's, contrary to what was commonly found in other studies, and capillary coefficients of adobe were comparable to lime stabilized adobe from other regions. A surface protection by compatible renders, 2 respectively earthen-based and air lime-based, is strongly encouraged to extend the walls durability. Although based on a short sampling, this data gives initial support to future compatible, effective and reversible interventions in Leiria vernacular earthen buildings, contributing to the preservation of this earth-built heritage.

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In this paper the characterization of a gypsum plaster sample from the end of the 19th century simulating imperial red porphyry using a multi-analytical approach is presented and discussed. The results of X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TGA-DTA), physical and mechanical properties are summarized. In order to have further insight into the microstructure, polarized light microscopy (PLM), scanning electron microscopy coupled with energy dispersive X-ray spectrometer (SEM-EDS), and micro Raman spectroscopy analyzes were also made. They helped to clarify the main issues raised by the other complementary analytical techniques and allowed the establishment of interrelations between the different properties, providing important information about the materials, the skills, and the technological development involved in the art of imitating noble stones with gypsum pastes. This study also contributes to our knowledge concerning the preservation of these types of elements that are important in the context of European decorative arts and rarely reported in the literature.

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Incorporating phase change materials (PCM) in plasters is an effective solution both for more efficient use of energy and its consumption reduction, because it allows the use of free energy in the environment, by latent heat storage. As PCM has not binder properties, it is expected to decrease mechanical properties of the final mortar. Also the density of the mortar decreases due to PCM lighter specific weight. In order to be used as a final coat for wall plastering, it must verify the requirements of the respective European Standard. This paper presents the results of the composition development and mechanical properties (flexural, compressive and adhesive strengths) testing and validation of three different gypsum mortars, in order to select the appropriate one for thermal testing in test cells. The results show that the effective decrease in the studied characteristics of the mortar does not inhibit the use for plastering, as requirements are achieved by the three studied compositions.