Ventilated Glazed Protection System
There will be an ideal space of 25mm -
50mm between the existing leaded / stained glass window and the new ventilated protective glazing system. This
system will allow a “chimney” type flow of air, thus creating the correct
environmental conditions for the future preservation of the leaded glass. The
6.4 laminated safety glass will be edged around the perimeter with 12mm lead.
This 12 mm lead replicates the lead edging on the internal leaded / stained
glass. The lead edged laminated glass is glazed tight against the vertical edges
of the stonework. The bottom horizontal edge is glazed within a brass angle with
beads, and fixed at the sides. We allow a 15mm-20mm air gap from base of stone
to allow sufficient ventilation. The height will be divided into sections, by
brass T-section and secured by beads. The horizontal divisions will be located
to correspond with the horizontal divisions of the existing leaded / stained
glass window. We will allow an air gap at the top arch. The glass will be cut
shy at the top to leave a triangle shaped space Approximately 50mm x 100mm. This
will be in filled with clear nylon mesh cut to the contours of the stonework.
Advantages of glass
1. The laminated glass also has UV protection, thus protecting the glass /
enamel colours and resin bonds.
2. Glass will not scratch during cleaning
3. It will provide insulation to the church.
4. It has no visual impact from the interior.
Disadvantages
1. Laminated glass can break upon the impact of a very heavy object such as a
brick. However, the glue which laminates the glass will hold it in place,
retaining protection of the window. Singular broken sections can easily be
replaced.
2. As with all sheet glazing, we have to consider the negative impact of the
reflective light on the surface. There has to be some compromise to protect the
stained glass.