The final part of Rosslyn Chapel’s long-term conservation programme has now started with work underway to install environmental protective glazing on the external face of the sixteen ground floor stained glass windows.
Mark Bambrough, a Partner with Scottish Glass Studios, said: ‘This conservation approach was required due to excessive paint loss found within the ground floor windows and the need to arrest further decay. Over the past two years, a test bed has been in place to establish if the proposed installation would function and, following rigorous sampling and monitoring, both technical parameters and an exterior aesthetic appearance has now been agreed by Rosslyn Chapel Trust, Historic Scotland and Midlothian Council.’ As part of the main conservation project, all ground floor windows were removed and taken to the Scottish Glass Studios, in Glasgow, for conservation repair and cleaning.
A system of externally ventilated environmental protective glazing was chosen due to the significance of the internal carving around each window. This means that the stained glass will be relocated back into its original glazing groove and the window protection will sit within the exterior masonry, with a 30mm cavity. Ventilation will be provided by vent slots at the top and bottom of the protection system. The glass type chosen for installation is a tinted glass with an etched surface.
Ian Gardner, Director of Rosslyn Chapel Trust, said: ‘The most important conclusion to be drawn from the test is that the environmental protection system works as intended with no condensation being detected on the painted surface of the stained glass. Without this, it is clear that further damage would be caused to the stained glass windows and so this work will help ensure the long-term conservation of the windows, which are an important feature of the Chapel.’
The current conservation work is being supported by the Heritage Lottery Fund and work will be completed by Christmas. Some scaffolding will be in place around two windows at a time to allow work to be carried out.
Rosslyn Chapel’s stained glass windows were designed by Clayton & Bell of London and were installed between 1867 and 1887, with two of the clerestory windows following sometime after 1893. There is no evidence of any previous use of stained glass in the Chapel, which was built between 1446 and 1484.