If you saw switchable privacy glass in a boutique hotel and now want it in your own bathroom, this is the honest homeowner guide. What it costs, what it looks like on a wet Tuesday morning, and where it makes sense versus where you should just buy a good blind. What residential smart glass actually is PDLC (polymer-dispersed liquid crystal) film laminated between two panes of tempered glass. Flip a switch, the liquid crystals align and the glass becomes transparent. Cut the power, they scatter, and the glass becomes opaque. Switching time is under 0.1 seconds. The four residential use cases that actually make sense 1. Ensuite bathroom facing the bedroom Modern primary suites with open-concept ensuites are the killer app. A smart-glass wall lets the bathroom feel like part of the bedroom during the day (natural light, sight lines) and disappear behind an opaque wall when in use. 2. Master shower enclosure Sculptural glass shower with view of the bedroom or, in a walkout basement, the yard. Smart glass gives privacy on demand without shower curtains or permanent frosting. 3. Home office door / meeting nook Sound isolation stays intact; the glass just goes opaque for video calls or focused work. Perfect for the rise in home-based professional practices. 4. Powder-room doors Guests walk toward what looks like a solid opaque door, touch the handle, and the glass clears briefly show…