What is spandrel glass and why is it a crucial part of the aesthetic design of a building?
One definition is the following:
Spandrel glass is an opaque glazing product designed in order to help hide features between the floors of a building, including vents, wires, slab ends and mechanical equipment.
But, that definition is just the beginning for the usage of spandrel glass and leaves out a very important reason for usage. Spandrel glass gives the architectural team another design item to work with.
There are many styles of spandrels and most people assume those options are colored paints. Typically, the choices have been dark colors- predominantly black, gray, and dark greens. These colors have been in the market for many years and there is a comfort level with their usage.
However, in the past few years other high quality, innovative, and beautiful options have arisen. Foremost among them is the usage of acid etched glass in the spandrel glass area.
Products in this class include:
- Walker Textures® Satin
- Walker Textures® Opaque
- Walker Textures® Velour
The Walker Textures® products mentioned above have multiple usages, giving the design team options that they never had previously. The biggest and most prominent advantage of using acid etched glass is the fact that the etching can go on one or both sides of the glass and on any of the 4 surfaces of the insulating glass unit featuring a spandrel need.
In fact, acid etched glass offers the ability to go on surface 1. These applications are used for a number of purposes such as glare reduction, enhanced color rendering when combined with color on the opposite side of the glass, and the ability to achieve depth in the glass unit. In addition, it is also now used for bird safe properties; though make sure you are specifying a specific etched glass when it comes to bird friendly. Not all spandrels or etches are the same in that regard. See the Walker Textures AviProtek® specifications for more information.
It also should be noted that the acid etch options from Walker Textures® can also be fabricated in monolithic (tempered or heat strengthened) or laminated.
In addition to the great surface and product application flexibility, acid etched glass also offers excellent harmonization properties. The designer now can get a clean and consistent look throughout the glazing area. If the designer has a desire to enhance the color from the framing, brick, or stone on the building, the acid etched option is a fantastic way to achieve that.
In some circles the overall durability of acid etch on an exterior project may be questioned, however the reality is that acid etch is not a coating, (like some of the other more traditional spandrel glass products) and its resistance properties in exterior conditions are essentially equivalent to un-etched glass. Its unique closed-pore surface structure resists staining and allows for easy cleaning.
Another potential concern is the translucent properties of etched glass. When viewed at a very close distance, acid etch in a spandrel application can show the details behind it, though it will be obscured of course. However as you move away from the glass, those items will no longer be perceptible. In a commercial structure, especially ones that are 2 floors and higher, the ability to get “close enough” to the glass to see anything behind it is virtually impossible. This concern really would only come into play for a structure where the glass is accessible from the ground floor and even then, it will not be the case with a finish with low translucency.
In the end, the usage of products like Walker Textures® Satin, Opaque, and Velour are an excellent additional approach for the design team to consider when they are looking at how their spandrel area will take shape.