Product selection
Does reflective window film work at night?
No. Reflective film mirrors on whichever side is brighter. During daylight that is the exterior, so the glass screens from outside. After dark with interior lighting on, the relationship inverts and the interior becomes more visible than through untreated glass. Reflective privacy should never be sold as nighttime privacy.
This is the single most common disappointment in commercial film work, and it is entirely avoidable. Any installer who describes reflective film as one-way privacy without qualifying it is setting up a complaint.
Where privacy must hold at all hours — exam rooms, behavioral health, conference rooms, HR offices, restrooms — the correct product is a diffusing frosted or patterned film, which obscures sight lines from both sides regardless of lighting.
Where the requirement is daytime screening plus heat rejection, reflective film is genuinely a strong answer, and pairing it with blinds or shades covers the after-dark condition.
Technical performance, service life and warranty terms come from current 3M documentation for the specific product and application. We attach those documents to proposals rather than paraphrase them.