If your client just wanted the glazing to be permanently obscured, you can probably go for ceramic frit as someone had suggested or film adhesion as another had suggested or laminated glass with opaque PVB interlayer.
If they wish to control at will between total clarity and totally obscured, interstitial blind or integrated blind is one option. The downside is, as in anything mechanical, it breaks down even though they are typically motorized for interstitial blind. The other possibilities is the smart glass that is available in the market in the recent years. You can have a choice of electrochromic glass.eg Sage, LCD glass eg Polyvision switchable glass or thermochromic filter eg Suntuitive interlayer in laminated glass
The choice is really quite wide and affordable these days. Some of them are even good enough for exterior use and so durability is not really an issue.
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Geok Ser Lee Intl. Assoc. AIA, LEED AP
Owner
GSLA
Irvine CA
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