Correspondence: Jorge de Brito, Department of Civil Engineering and Architecture, Section of Construction, IST — Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal. Tel: (351) 21 8419709; Fax: (351) 21 8497650; E-mail: jb@civil.ist.utl.pt

¹is an architect and has an MSc in Construction from IST — Technical University of Lisbon. His research is concerned with the inspection, diagnosis, and rehabilitation of ancient gypsum plasters.

²is a civil engineer from IST — Technical University of Lisbon and received her doctoral degree in civil engineering from Faculdade de Engenharia da Universidade of Porto (FEUP), and is a senior researcher in the National Laboratory of Civil Engineering (LNEC). She is the Portuguese expert in the European Normalization Committee for rendering and plastering mortars and in the EOTA Working Group for preparation of an Approval Guide for External Thermal insulation Composite Systems. She is also a member of the RILEM Committee for Repair Mortars for Historic Masonry (RHM). She collaborates in several Masters Courses in Civil Engineering and Architecture of Universities of Lisbon, Coimbra, and Porto. Her research work is related to the performance of wall-covering systems, the durability and rehabilitation of wall coverings, and the conservation of historic mortars.

³graduated in Civil Engineering and received his Masters and Doctoral degrees at IST — Technical University of Lisbon, Portugal, where he is currently an associate professor. He is a member of IABSE, FIB, CIB, and IABMAS, as well as of several reputed national engineering societies and is a member of the following working groups: CIB W80/RILEM 100-TSL — Service Life Prediction of Building Materials and Components; CIB W86 — Building Pathology; CIB W115 — Construction Materials Stewardship; and several national committees under CEN. His research work deals with deterioration, rehabilitation, and management of concrete structures. He has co-authored the 'Handbook of Concrete Bridge Management', published by ASCE Press in 2004.

Received 23 June 2007; Revised 23 June 2007.

Abstract

The rehabilitation of ancient gypsum plasterwork demands a systematic procedure in order to obtain a complete knowledge of the action's context, to identify the main anomalies, and to select the materials and techniques needed for their performance. The characteristics of construction elements demand also that actions are subjected to a strict planning, using a procedure where observation plays a fundamental role in identifying and inspecting the various components of the plastered element. This paper describes a methodology proposed for the rehabilitation of ancient gypsum plasterwork comprising the appraisal and inspection of the building's conservation status, the analysis of the data collected, the preparation of restoration project, and the decisions made on site.