Silvia R. M. Pereira

National Laboratory for Civil Engineering, Lisbon

Architectural Azulejos: challenges in their conservation

Abstract

 The historic ceramic tiles –azulejos- are one off, if not the, most important contributions of Portugal to the cultural heritage of Europe. Azulejos have been used uninterruptedly since the 15th to 21th century being ubiquitously found as decoration in architecture throughout the country. Their large amount and common architectural setting, many times in exterior environments, rends them highly susceptible to degradation and vandalism. It is a major issue that many tile panels are badly in need of conservation especially as result of this exposure to weathering conditions and salt damage. An accentuated decay has been observed in the last decades which urges researchers to find prevention and conservation treatments to safeguard this heritage. Knowing azulejo’s degradation mechanisms and how to conserve and restore them is therefore highly important. The study of commonly used conservation materials and methods aids research to develop and improve more efficient, compatible and lasting conservation options. An overview of the research performed regarding the most common conservation challenges - fragment adhesion, ceramic consolidation and glaze lacunae infill - is made, together with efforts in developing novel conservation treatments that try answering the azulejo conservation challenges. The filling of glaze and ceramic tile lacunae in historic tiles in-situ and in an architectural context is considered one of the most challenging treatment since there exists no material that satisfies both efficacy, compatibility and adequate ageing behaviour. Several types of solutions such as the use of alkali activated aluminosilicates or “geopolymers”, zinc hydroxychloride mortars, azulejo’s re-firing or localized CO2 laser re-glazing of lacunae (together with FORTH) are being studied to overcome this difficult challenge.  

This talk will dwell on Portuguese azulejos, their main degradation mechanisms and studies in conservation regarding their safeguard.



Date: 22/6/2017
Time:12:00 (coffee & cookies will be served at 00:00)
Place:Seminar Room 1