For the preservation of historic monuments and buildings, at present, exterior protective glazing provides the most acceptable protection for endangered historic church windows. The storage conditions in-situ should match those adopted in a museum, but without interfering with the actual substance of the glass. In addition to protecting against corrosion, exterior protective glazing will provide direct protection against the weather, soiling and vandalism. In extreme conditions, it is recommended to use laminated safety glass. In addition, protective glazing provides the extra benefit of restricting the loss of heat, which is an important factor in these times of high energy prices.
Extensive scientific research has proven the beneficial effect of protective glazing. Simultaneously, these examinations have revealed several criteria that an effective protective glazing system should fulfil:
- Functional ventilation to the rear of the window between the protective glass pane and the original glass.
- A sufficiently sized gap achieves an optimal air cushion between the open air and the ambient indoor climate.
- Stable construction
- Collection and discharge of condensation via the lead drain pipes at the base point of the protective glazing.
- Heat insulating seals between the exterior protective glazing and the stonework comprising of porous limestone and glazier’s putty between the metal frame, the iron and the exterior protective glazing.
On the outside, protective glazing reflects, which does impair the aesthetic picture quite significantly. The intrusion is justified to preserve the original composition.
The unwanted exterior reflection is mitigated by using machine drawn Goethe glass, which distorts the reflection through slight streaks and irregularities on the surface caused during the drawing process. Experience has shown that the reflection will be reduced by layers of dirt settling on the pane over the years. We have created a number of protective glazing systems using glass with an antireflective coating or over-fired and slightly patterned glass.
We always adapt the protective glazing individually to the requirements of the building and/or the client. We develop tailor-made solutions.
