Reflective window film (one-way mirror)
Reflective window film — also called one-way mirror film or one-way reflective film — carries a metallised or ceramic layer that bounces light back off the brighter side of the glass. During daylight hours the outside is brighter, so the window reads as a mirror from the street while you look out normally from inside. Because it is working on light rather than opacity, it is the only privacy option that preserves your view — which is why it belongs on living rooms, home offices and any window with an outlook worth keeping.
Reflective films also reject a serious amount of solar heat, so a west-facing lounge that gets privacy also gets a cooler afternoon. The trade-off is the night-time reversal: once your interior lights are the brighter source, the mirror flips and you become visible. Plan for a sheer or blind on rooms you use after dark, or step up to frosted film if 24-hour privacy matters more than the view.
Related: residential window tinting, 3M window tinting and All-Season window insulation film if winter warmth is your main goal.

