The 35% rule,
in plain English.
It is not the film that has to hit 35% — it is the film and your glass together. That catches a lot of people out.
35% in front. Behind you, it depends on the vehicle.
Front side windows must keep at least 35% overall visible light transmission — overall meaning the glass and the film together, not the film on its own. Behind the driver the limit depends on what class your vehicle is, and most people are surprised by which way round it goes.
Minimum overall VLT once film is on. Front sides on every vehicle class; an ordinary car (class MA) keeps 35% at the back too
Minimum overall VLT. Only an anti-glare band along the top is permitted
Allowed for variation between films and light meters
Your glass is already tinted
Most factory glass is not clear. A car that measures 75% VLT before any film cannot take the same shade as one measuring 88% and stay legal. That is why we measure your glass first and quote the shade second — the same film is legal on one car and not on another.
We measure, then recommend
Your branch puts a meter on the glass before suggesting a shade, so the number you end up with is the number on the car.
We check your class first
Whether you can go dark at the back depends on the vehicle class on your registration, not on how the car looks. We check it before quoting a rear shade.
It is checked at WoF
Non-compliant front tint can fail a warrant of fitness. Getting it measured up front is cheaper than stripping film later.
What you can do behind the driver
The front is the same for everyone. The back is not. An ordinary sedan or hatch is class MA and has to keep 35% all the way round; a genuine off-roader or a ute can go as dark as you like behind the driver.
| Class | What it is | Behind the driver |
|---|---|---|
| MA | Ordinary car — sedan, hatch, wagon, up to 9 seats | 35% minimum |
| MC | Off-road passenger vehicle — 4WD plus off-road design features | Any shade |
| NA | Light goods vehicle up to 3.5t — utes, vans | Any shade |
| MB | Forward-control passenger vehicle, up to 9 seats | Any shade |
| MD / ME | More than 9 seats — people movers, buses | Any shade |
Swipe sideways to see the rear limit.
Whatever the class, a vehicle with film on a rear window must have an external mirror on both sides.
Anyone reading this table is deciding how dark to go at the back — see it on the car, front and rear separately.
What the numbers mean
Every Zivent product page lists these. Here is what each one actually tells you.
Visible light transmission. The percentage of visible light that gets through. Lower VLT means a darker film. This is the number NZ law is written around.
Infrared rejection. Infrared is the part of sunlight you feel as heat on your arm, so this is the number that tracks how much cooler the cabin feels.
Ultraviolet rejection. UV is what fades your dashboard and damages skin. Every Zivent film blocks 99.9% of it, at every shade.
Total solar energy rejection. The broadest measure — visible, infrared and UV combined. The single best number for comparing heat performance between films.
Visible light reflection, quoted for the inside and outside faces. High exterior VLR is what makes a film look like a mirror.
Solar heat gain coefficient. How much solar heat passes through the glass overall. Lower is better.
What can your vehicle take?
The table above turns on a class most owners have never looked up. Answer what the vehicle is instead and it works the class out — then shows the limits, front and rear.
Tint law questions we get
What is the legal tint limit in New Zealand?
The windscreen must keep 70% and the front side windows 35% overall visible light transmission, on every vehicle. Behind the driver it depends on class: an ordinary car (class MA) also has to keep 35%, while an off-road passenger vehicle, ute or van can be any shade. Any vehicle with film on a rear window needs an external mirror on both sides.
How long does tinting take?
Two front windows take around 40 minutes. A full vehicle is two to three hours depending on the shape of the glass and how much preparation it needs. Leave the windows up for two to three days afterwards while the film cures.
Can you tint over factory tint?
Yes, and that is the normal case — factory glass is rarely clear. It is exactly why the measurement matters: the film and the glass are counted together against the 35% limit.
Will tint fail a warrant of fitness?
It can, if the front side windows come in under 35% overall, or the windscreen under 70%. On an ordinary car the rear glass is held to 35% too. A 5% tolerance is allowed on the meter reading. If you are unsure about film already on the car, any branch can measure it.
What happens if my car cannot take the shade I want?
We tell you before we fit anything. Usually the answer is a lighter shade on the fronts and the shade you wanted on the rears — which is what most customers do anyway.
Please check for yourself too. This page is a plain-English summary, not legal advice. Legal compliance depends on your specific glass and film combination measured together. The authority is NZTA Waka Kotahi.
NZTA: windows, wipers and mirrors →
The inspection rule itself (VIRM 5-1 Glazing) →
Not sure what your glass reads?
Your branch puts a meter on the front glass before recommending a shade, so the number you end up with is the number on the car. Ask for a reading with your quote — any branch can measure film that is already on the car, too.