The application of exterior protective covering has advantages and disadvantages. The advantages apply only if the protective covering is installed properly. Research indicates that if installed improperly, protective covering can cause premature deterioration of the stained glass and accelerate structural failure. Modern day plastics, acrylics, and polycarbonates (Lexan), have excessive expansion and contraction properties, among other detriments, and will not maintain a proper perimeter seal. Plate glass, safety laminate and tempered glass are more stable, have less expansion and contraction properties, will maintain clarity and are more sensitive to the architectural style of the building.
Venting the air space between the stained glass and the exterior protective covering will alleviate the thermal pressure and help eliminate the possibility of condensation. There are many different stained glass installation techniques, each offers its own venting solutions.
Are you interested in an on-site conditions report of your stained glass windows and advice for the application of exterior protective covering? Contact us.