How is privacy glass made dark?
The glassmaker changes the glass’s chemical make-up. AGC’s privacy glass page credits the darkness to a change in the glass’s chemistry, and says each carmaker picks the light transmission it wants for a given model. The glass comes in grey or green, and AGC names side glass, back glass and roof panels as its uses.
AGC measures its glass to ISO 9050 and publishes three ranges:
| AGC privacy glass, ISO 9050 | Range |
|---|---|
| Light transmission | 4.5 to 40% |
| Total energy transmission | 29 to 45% |
| UV transmission | 0.2 to 7% |
Those are transmission figures, the share let through. Film makers print UV and solar energy as the share stopped, so those numbers need flipping before they can be compared; light transmission is stated the same way by both.
How is privacy glass different from window film?
The colour is part of the glass itself; film is a separate layer applied to the inside afterwards. That has three practical results:
- It can’t be lightened. Factory tint stays until the pane is replaced.
- Film stacks on top. Light transmissions multiply, so 50% film over 20% glass leaves about 10%. The tint stacking calculator does the sum for any pair.
- The numbers come from different tests. LLumar rates its film on clear 6 mm glass under NFRC guidelines, AGC rates its glass under ISO 9050, so the film against privacy glass comparison treats them side by side rather than as one scale.
Figures for particular cars and glassmakers are gathered in how dark privacy glass gets.
Is factory privacy glass legal in BC?
Yes, where the carmaker put it. Tint built into the glass is judged under MVAR s. 7.05(9) against the federal safety standard, not under the film rule in s. 7.05(8). Inspectors read the glazing mark on each side window, and BC’s 2025 Vehicle Inspection Manual lets an AS-3 mark pass only on a pane behind the driver’s position (item 13c). What those marks mean is explained under AS-1 line, and the legal detail is in factory privacy glass and BC law.
Adding film over privacy glass at Brookswood Tint
Have the glass metered first, then choose the shade for the result you want rather than the number on the film. Dark ATC over privacy glass gets very dark quickly; clear AIR adds infrared rejection, 60% IRER for AIR 80 on LLumar’s sheet, while taking away less light than any tinted shade, since it measures 77% VLT. The seven-window SUV package is described on SUV window tint, and tinting over factory tint works through shade choices.