Contract No: EVK4-CT-2001-00045
Starting date: 1 February 2002
Duration: 36 months


The VIDRIO project started on the 1st of February 2002 and it will develop for 3 years a study focused on the improvement of methods and technological systems in order to control and reduce damage on stained glass. Most European stained glass windows have no protection at all, being exposed to climatic influences, air pollution and biodeterioration. Although protective glazing system is widely accepted, many open questions remain and certain reservations do still exist in the mind of owners, curators and architects.

Sainte Chapelle: detail

Sainte Chapelle: inner front



Sainte Chapelle

Three key monuments will be considered, the Sainte Chapelle in Paris and the Cologne Cathedral, both included in the UNESCO's World List of Cultural Heritage, and Saint Urbain church in Troyes, France. In these buildings monitoring will be performed on windows, with different exposures, in the actual situation. The environmental impact on the stained glass with and without their protective systems will be particularly studied as a consequence of the daily and seasonal cycles of the climatic and other environmental variables (e.g. visitors, heating and air-conditioning systems, infiltration of polluted air from outside).

Cologne Cathedral



The innovation of this project is to provide for the first time a global, multidisciplinary approach where research, industry and final users are present, aimed to identify the best preventive strategy in view of the local climate, pollution, biological activity, and building exploitation. Each partner will contribute to the developement of the knowledge present in his country, taking into consideration also the research made in the other European countries.
This project will concentrate on monitoring, evaluation and improvement of the environment for the conservation of stained glass windows with and without protective glazing.
The research is based on both laboratory study/simulation and field surveys to verify the results on the site. An assessment of the correlation between glass decay and weathering (physical, chemical, biological) both inside and outside, will be carried out. Data of the different risk parameters inside and outside the chosen buildings will be obtained on the site, using integrated multidisciplinary and complementary methods.
The local climate (air temperature, dew point, relative and specific humidity, ventilation) and the microclimate concerning the stained glass under study (glass temperature, spread above the dew point, condensation and time of wetness, ventilation) will be monitored with automatic devices and special intensive field surveys. Continuous monitoring is necessary, as a complete yearly cycle has to be considered.
A new dew point sensor connected with an alarm system will be tested and improved in order to survey the condensation inside the interspace between the two glasses.
The glass surface deposition and air content of anthropogenic particles and natural particles will be studied both from the air (indoors and outdoors and in the interspace) and from the deposits on the glass surface.
Growth of micro-organisms
on samples and microbial contamination on glass and its direct environment will be examined.
Glass sensors
(slices of corrosion sensitive glass) and painted glass(panes) with historic compositions will be installed inside, in the interspace, and outside a protective glazing.
Successively, these panes will be analysed in the laboratory.
Analysis of selected original glass samples and simulation tests with painted glass samples will be carried out in laboratory, where these samples will be exposed to different weathering factors detected during on site measurements.

Sainte Chapelle
Example of deterioration
In particular this project intends:
  1. to establish a multidisciplinary approach in the identification of the most appropriate global methodology to preserve stained glass;
  2. to find suitable systems to monitor and control the deterioration of stained glass;
  3. to make historic buildings and churches accessible to crowds (of people) (e.g. mass tourism, holy liturgical ceremonies, concerts) but, at the same time, avoiding the risk of damage to stained glass by internal condensation;
  4. to propose a general directive on the most appropriate operative methodology for preserving historic stained glass;
  5. to provide a methodology and try to identify the thresholds of danger to preserve stained glass.

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