Stained glass: The impact of Florida’s tropical environment on these pieces indoors and the transformative effect of treatment

Julie Flynn and Yenny Cabrera Valdes


Florida’s sub-tropical environment frequently presents challenges to the care of historical built heritage and works of art. Even when placed indoors, the continental United States’ southernmost state’s high heat, humidity and coastal saline conditions subject most art materials to stresses, even when placed indoors. Stained glass windows, which are an amalgam of materials that are often used as architectural elements, can be particularly sensitive to these conditions. In 2018 and 2019, two Florida historic institutions—the Deering Estate in Miami, and the Lightner Museum in St. Augustine, —found themselves facing situations where historic stained glass collections exhibited condition issues that were either caused or exacerbated by climate issues. In both cases, the works had been obtained from other sources and exhibited as interior artworks.

The Charles Deering Estate’s windows, from pre-17th century Spain, were described in the estate’s 1924 inventory.  They had been in storage for years prior to conservation, and lead corrosion and a weathering crust on the glass surface were thought to have been caused or exacerbated by near 90% humidity at the coastal site. Similarly, the Lightner Museum of St. Augustine Florida owns fourteen (14) stained glass windows, dating from the 19th century in Chicago, exhibited bulging, broken solders, and cracked glass that were partially caused by water and humidity damage partially from Hurricane Irma’s damage to the museum building in 2017. as some of these windows were displayed on exterior interior walls.

The conservation campaigns for these two sets of stained glass collections occurred in two widely different regions of the state, however the root cause of damage could be linked in both cases to environmental issues that are distinctly Floridian in nature. This paper will demonstrate how treatment, storage, and installation choices were made, the dramatic transformation in the windows’ appearance, and the ensuing stability, of the wood, glass, and metal elements that resulted from treatment. 

2021 | Virtual | Volume 28