Matching Spandrel and Vision Areas
Often a project may require spandrel glass to harmonize with the vision areas of your building. However, this is sometimes difficult to achieve when high-light transmitting or low-reflective glass types are used. Low-light transmitting and high-reflective glass types provide the least contrast between vision and spandrel areas. Variable sky conditions can also influence our perception. On a bright, sunny day, the exterior light intensity is approximately 50 to 100 times greater than the interior lighting level.
When viewing the glass from the outside, the dominant visual characteristic is the exterior reflection. On gray, overcast days, a greater visual disparity is created between vision and spandrel areas due to the transparency of the vision glass and the perception of depth created by interior lighting. The non-vision areas tend to look flat and two-dimensional by contrast. By keeping the vision and spandrel glass construction similar (the same exterior glass color, coating, etc.) the contrast can be minimized under various lighting conditions. Uniglass recommends using a neutral colored ceramic frit on the fourth (#4) surface.
Uniglass recommends viewing glass samples or full-size mockups to match vision and spandrel glass areas when the visible light transmission of the vision glass exceeds 14 percent.
Moiré Pattern
Moiré is an optical phenomenon that may present itself as a “wavy, rippled or circular” pattern under certain conditions. Moiré patterns can be created whenever one semi-transparent object with a repetitive pattern is placed over another. The moiré pattern is not a glass defect, but rather a pattern in the image formed by the eye.